Eric Collet

Professeur des Universités - Responsable du département

Adresse courriel : eric [dot] collet [at] univ-rennes [dot] fr

Téléphone : +33 223236532

Numéro de bureau : Bâtiment 11A / Etage 1 - 124

What's new


Our paper is highlighted on the front cover of CrystEngComm

See our paper "Ferroelastic phase transition and the role of volume strain in the structural trapping of a metastable quenched low-spin high-symmetry phase in [Ru0.35Fe0.65(ptz)6](BF4)2".


Installation ceremony at the Institut Universitaire de France

The IUF medal was delivered during the installation ceremony of the new promotion of the Institut Universitaire de France. At this occasion, Olivier Houdé, IUF administrator, and Sylvie Retailleau, minister of research, talked about the important role of the IUF for developing research in universities.




Badminton in slow motion!

We were partner of the French Badminton Championships which took place at the Glaz Arena Rennes-Cesson from February 2 to 5, 2023

A good occasion to talk physics with many schoolchildren, to popularize science in the framework of an IUF project, the ANR IMAGES project of the University of Rennes "science with and for society".

High temporal resolution videos were made on this occasion, showing the deformations of the shuttlecocks over a few milliseconds, the deformations of the rackets or the rotation of the shuttlecock whose chirality allows it to turn on itself and stabilize.

The videos can be viewed here:

more information on this page.



Officialization in Tokyo of the international research laboratory DYNACOM

The creation of the international research laboratory DYNACOM was formalized on October 4, 2022 in Tokyo with the signing of the agreement by Antoine Petit, President-General of the CNRS, David Alis, President of the University of Rennes 1 and Teruo Fujii, President from the University of Tokyo, in the presence of Profs. S. Ohkoshi and E. Collet, directors of the IRL.

Strengthening of France-Japan collaboration in the field of materials: Dynacom (for Dynamical Control of Materials) is an international research laboratory (IRL) between the CNRS, the University of Tokyo and the University of Rennes 1. It is located on the Hongo campus, in Tokyo, Japan. This laboratory is the result of a long-standing collaboration, which began in 1996, between Japanese teams in Tokyo and French scientists from the Institut de Physique de Rennes. Joint research projects, exchanges of students and professors, study trips, for 26 years, scientists have used the full range of international collaboration tools offered by the CNRS, the University of Rennes 1 and the University of Tokyo, until setting up an International Research Project, named IM-LED, in 2016. A new milestone has now been reached with the creation of an IRL, which highlights this emblematic and strategic collaboration. The Tokyo Institute of Technology, Tohoku University, Kyoto University in Japan, and Nantes University in France will also be involved in the Dynacom laboratory.

learn more: Lien vers le communiqué de presse



Alajos Kálmán Prize for Éric Collet

The Alajos Kálmán Prize  goes to Professor Éric Collet from the Institute of Physics in Rennes, France, who performs his inspirational interdisciplinary research at the interface of material science, chemistry and physics with crystallography at the very heart of his work. Prof Collet is one of the pioneers who paved the way for the subsequent studies in the greatly innovative field of X-ray free electron lasers science. He with his collaborators made high impact studies of ultra-fast femto second experiments, ultra-fast photo excitations like photo induced structural dynamics, phase transitions and molecular switching.

His outstanding achievement is based on the structural study of molecular complexes and new transition mechanisms, especially from the molecular to the crystal scale.



Faraday Discussion issue: From optical to THz control of materials

It was a great pleasure to chair the Faraday Discussion meeting in London about ultrafast control of the physical properties of materials by light excitation and/or THz excitation. The unique format of the Faraday Discussions allowed for in-depth discussions, stimulating new thoughts and defining new horizons. The issue has now been published online.




Want to learn more about ongoing research in the field of ultra-fast phenomena in solid state?

Read papers in the special issue edited by Eric Collet and Sylvain Ravy



























Transitions photoinduites ultrarapides : un axe émergent pour la photonique

A lire dans Photoniques





Exploring ultrafast photoswitching pathways in RbMnFe Prussian Blue Analogue in collaboration with H. Tokoro and S. Ohkoshi's Group

On the cover of Angewandte Chemie    And selected as hot paper




Collaborating work with H. Tokoro and S. Ohkoshi's Group in Tokyo performed at the ESRF on the cover




Conférence à l'espace des sciences de Rennes le 26 janvier 2021


Espace des Sciences de Rennes




Nature Chemistry cover


Nature Chemistry Cover

Photoinduced charge-transfer can lead to various important and interesting phenomena, such as magnetism, ferroelectricity and photocatalysis. However, an atomic-scale description of the initial photoinduced process, which couples intermetallic charge-transfer and spin-transition, is still under debate because of the speed at which it occurs. Now, a team led by Eric Collet and Marco Cammarata have used femtosecond X-ray spectroscopy to reveal how photomagnetism emerges in cyanide-bridged CoFe coordination networks. They see that it is the spin-transition on the cobalt atom, occurring within ~50 fs, that drives the subsequent electron transfer from Fe (red) to Co (blue) within 200 fs.


Danse des électrons


Science Ouest

Chicken and egg question

Chicken? Egg? Well, to tell the truth, after performing the experiment we initially found that we went "home late"




Our last study published in Nature Chemistry: Charge-transfer driven by photoinduced spin-transition, this is the way!
Among photoactive materials, Prussian blue analogues (PBA) are of specific interest, as light can address a broad variety of functions: photoexcitation of the diamagnetic CoIII(S=0)FeII(S=0) system generates the magnetic CoII(S=3/2)FeIII(S=1/2) state, with a charge-transfer coupled to a spin transition on the Co. However, questions about the photoinduced processes were unanswered. Does charge-transfer induce spin-transition or vice versa, which is the way?



In our paper entitled "Charge-transfer driven by ultrafast spin-transition in a CoFe Prussian blue analogue" published in Nature chemistry ( we reveal the process, thanks to the element-specific X-ray absorption data, measured at both the Fe and Co K-edges, allowed for monitoring the ∼50 fs dynamics of the spin transition around the Co and the ∼200 fs Charge-transfer dynamics. This study, including also optical spectroscopy data and DFT calculations, demonstrates that it is the elongation of the Co-N bonds, induced by the optical excitation, which drives the charge-transfer.

To learn more about this work, read what's "Behind the paper" here:



See also :



Communiqué du CNRS :



Médaille d'Argent CNRS


Vidéo médaille Argent CNRS

Eric Collet, Professeur à l'université de Rennes 1 et membre de l'IPR, se voit attribuer la médaille d’argent 2020 du CNRS.
Cette distinction récompense l'originalité, la qualité et l'importance des travaux des chercheurs au sein des laboratoires du CNRS.



Read the news in Angewandte Chemie Int. Ed.


Angew. Chem. I.E.






La 17ème édition des Journées de la Matière Condensée




Nous avons le plaisir d'organiser la 17ème édition des JMC qui se tiendra à Rennes du 23 au 27 août 2021. Les thématiques abordées couvrent l’ensemble des domaines relevant de la matière condensée, des concepts aux applications et souvent aux interfaces avec d'autres disciplines. Le succès de ces journées en fait le plus grand congrès national de physique de la matière condensée en France avec plus de 500 participants.

Espérant vous voir nombreux aux prochaines JMC à Rennes,
Eric Collet et Isabelle Cantat (Présidents du comité d’organisation)
Olivier Sandre (Président de la Division Matière Condensée de la SFP).



10 ways SLAC’s X-ray laser has transformed science

Ali Sundermier highlights 10 ways in which the world’s very first X-ray laser capable of imaging matter at the atomic scale, by generating X-ray pulses a billion times brighter than anything that had come before and producing X-ray laser pulses that would last for just femtoseconds, millionths of a billionth of a second.
One of them is "watching molecules breathe", which we published in in Nature Communications.


Front cover for our work with S. Ohkoshi and H. Tokoro performed at ESRF:
The Front Cover shows the ESRF synchrotron, where we studied the evolution of the crystal structure of the RbMnFe Prussian blue analogue by X-ray diffraction. We used a single laser shot for driving a phase transition in which photoinduced charge transfer, trapped by the structural reorganization, is responsible for the change in the magnetic properties of the system.
This work was performed in the frame of the IM-LED international laboratory (LIA, CNRS), JSPS, and ANR grants with a PhD funding from University Rennes 1.




Hot paper in PCCP:
Our paper "Temperature dependence of the cooperative out-of-equilibrium elastic switching in a spin-crossover material" has been selected by our Editors as a 2019 HOT Physical Chemistry Chemical Physics article. As part of the 2019 HOT articles collection, our article is free to access until the end of July 2019.




Game of Thrones:
In this special issue of Science&vie, I have made some estimate of the energy delivered by Viserion and that's impressive. His power is as high as the one delivered by our femtosecond lasers! Read more here:
"Game of thrones et la science" — édition spéciale de Science & Vie


Louis Ancel Prize of the French Physical Society



Eric Collet has been awarded the Louis Ancel prize of the French Physical Society (SFP) for his achievements in condensed matter physics. He delivered a plenary talk during the JMC 2018 meeting in Grenoble, where he received the award from Olivier Sandre (president of the SFP Condensed matter division) and Catherine Langlais (president of the SFP).

Read more on the website of the university


Joint Conference of the Pan African Conference on Crystallography (PCCr2) and the African Synchrotron Light Source (AfLS2)

I gave an invited plenary lecture in Accra during the joint AfLS2 and PCCr2 conferences, designed to bring together crystallographers, mineralogists and solid state scientists from Africa and beyond. The aim is to promote crystallography and explore educational opportunities for researchers in the field.

What I enjoyed: the talking stick!




Lattice phonon modes of a molecular spin-crossover crystals
We studied lattice phonon modes of a spin-crossover crystal in the frame of the international laboratory IM-LED, in collaboration with the group of K. Tanaka at Kyoto Univervisty, G. Chastanet's group at ICMCB in Bordeaux and S. Matar in Lebanon.




Interview in Sciences Ouest





Our collaboration with Japan highlighted at the city hall of Rennes. Isabelle Pellerin (Rennes) and David Alis (President of UR1) underlined the important contributions of Prof Shin-ya Koshihara for the development of Japan-France collaborative programs and of Prof Shin-ichi Ohkoshi, who is co-director with Prof. Eric Collet of the International Laboratory IM-LED :




We organized the first edition of the "Ultrafast Control of Materials" school and symposium at
the University Rennes 1 from Monday 11th to Thursday 14th June 2018.

More than 80 researchers and students participated to the meeting.

UCM2018 gathered experts interested in the study of the control of the physical properties of materials with a special focus on ultrafast science. Topics covered during this meeting included recent advances in photoinduced phenomena, non-linear phononics, THz science, elastic cooperativity, strong electric field effects and X-FEL science. The goal of this meeting is to have intense and frank scientific exchanges in a very friendly atmosphere on the emerging topics appearing with new laser-based techniques for controlling and understanding materials at work.



Learn more about the meeting here:

UCM2018 is supported by: the CNRS, Univ Rennes 1, the SFP, the ANR, the Université de Rennes 1, Université de Nantes, Université du Maine, Université de Versailles de Saint-Quentin-en-Yvelines, and four universities from Japan, the University of Tokyo, Tokyo Institute of Technology, Tohoku University, and Kyoto University.




Fast & Ferrous!




Electronic and structural dynamics during the switching of the photomagnetic complex [Fe(L222N5)(CN)2].

The [Fe(L222N5)(CN)2] compound is a photomagnetic FeII (ferrous) based coordination compound, which undergoes light-induced excited spin-state trapping (LIESST). The low spin state is hexacoordinated and the high spin state heptacoordinated. This system also serves as complex for the design of trinuclear or one-dimensional compounds made of other types of bricks with diverse coordinated metals. Here we study its ultrafast spin-state photoswitching dynamics, by combining femtosecond optical spectroscopy and femtosecond X-ray absorption measurements at the XPP station of the X-ray free-electron laser LCLS. DFT and TD-DFT calculations are used to interpret experimental findings. These studies performed in the solution phase show that LIESST in [Fe(L222N5)(CN)2] occurs on the 100 fs timescale under different types of photoexcitation. In addition, we observe coherent oscillations resulting from the structural dynamics accompanying LIESST, which were recently evidenced in more conventional octahedral FeIIN6 systems.

S. Zerdane, E. Collet,* X. Dong, S. F. Matar, H. F. Wang, C. Desplanches, G. Chastanet, M. Chollet, J. M. Glownia, H.T. Lemke, M. Lorenc, M. Cammarata,*
Electronic and structural dynamics during the switching of the photomagnetic complex [Fe(L222N5)(CN)2]
Chemistry A European Journal doi 10.1002/chem.201704746 (2017)

This study is in direct relation with our paper publihed in Nature Communication:




Chemical Reviews: M. Chergui and E. Collet

Photoinduced structural dynamics of molecular systems mapped by time-resolved x-ray methods.


Chemical Reviews

We review the tremendous advances in ultrafast X-ray science, over the past 15 years, making the best use of new ultrashort x-ray sources including table-top or large-scale facilities. Different complementary x-ray based techniques, including spectroscopy, scattering and diffraction, are presented. The broad and expanding spectrum of these techniques in the ultrafast time domain, is delivering new insight into the dynamics of molecular systems, of solutions, of solids and of Biosystems. Probing the time evolution of the electronic and structural degrees of freedom of these systems on the timescales of femtosecond to picoseconds delivers new insight into our understanding of dynamical matter.

Chemical Science:
Comparison of structural dynamics and coherence of d-d and MLCT light-induced spin state trapping

S. Zerdane, L. Wilbraham, M. Cammarata,* O. Iasco, E. Rivière, M.-L. Boillot, I. Ciofini, and E. Collet


Chemical Science

Light Induced Excited Spin State Trapping (LIESST) in FeII spin-crossover systems is a process switching molecules from low (LS, S=0) to high spin (HS, S=2) states. The direct LS-to-HS conversion being forbidden by selection rules, LIESST involves intermediate states such as 1,3MLCT or 1,3T. The intersystem crossing sequence results in a HS state, structurally trapped by metal-ligand bond elongation through the coherent activation and damping of molecular breathing. The ultrafast dynamics of this process was so far investigated in FeN6 ligand field systems, under MLCT excitation. Here we study LIESST in an FeIIN4O2 spin-crossover material of lower symmetry, which allows quite intense and low-energy shifted d-d bands. By combining ab-initio DFT and TD-DFT calculations and fs optical absorption measurements we demonstrate that, compared to MLCT, d-d excitation induces faster LS-to-HS switching and that the shorter intermediates enhance coherent structural dynamics.


Nature Communication:

Coherent structural trapping through wave packet dispersion during photoinduced spin state switching

H. T. Lemke*, K. S. Kjær, R. Hartsock, T. B. van Driel, M. Chollet, J. M. Glownia, S. Song, D. Zhu, E. Pace, S. F. Matar, M. M Nielsen, M. Benfatto, K. J. Gaffney, E. Collet, Marco Cammarata*


Nature Communication

The description of ultrafast nonadiabaticchemical dynamics during molecular photo-transformations remains challenging because electronic and nuclear structures impact each other and cannot be treated independently. Here we gain new experimental insights, beyond the Born-Oppenheimer approximation, into the light-induced spin-state trapping (LIESST) dynamics of the prototypical [Fe(bpy)3]2+ compound by time-resolved XANES spectroscopy at sub-30-femtosecond resolution and high signal to noise ratio. The electronic decay from the initial optically excited electronic state towards the high spin state is distinguished from the structural trapping dynamics, which launches a coherent oscillating wave packet (265 fs period) clearly identified as molecular breathing. Throughout the structural trapping, the dispersion of the wave packet along the reaction coordinate reveals details of intramolecular vibronic coupling before a slower vibrational energy dissipation to the solution environment. These findings revisiting the LIESST process illustrate how modern time-resolved XANES provides key information to unravel dynamic details of photo-functional molecules.


International Laboratory between France and Japan:

News :
Univ. Rennes 1 :
Univ. Nantes :
Univ. Versailles St Quentin :
Tokyo Tech english :
Tokyo Tech Japanese :


Elastically driven cooperative response of a molecular material impacted by a laser pulse


Nature Materials



Order, better, spin cross-over

Work it harder, make it better, describe order, our work on spin-crossover (Daft Punk’s summary version!).

Hiroshi Watanabe, Koichiro Tanaka, Nicolas Bréfuel, Hervé Cailleau, Jean-Franǫis Letard, Sylvain Ravy, Pierre Fertey, Masamichi Nishino, Seiji Miyashita, and Eric Collet
Ordering phenomena of high-spin/low-spin states in stepwise spin-crossover materials described by the ANNNI model
Physical Review B 93 014419 (2016)



Research topics

In molecular materials, interactions brought into play result in fragile equilibrium between multistable states, switchable under the effect of temperature or pressure and we are investigating how light can switch them.



Our team is investigating the mechanisms driving these switching at thermal equilibrium or in highly out-of-equilibrium dynamics by using state-of-the art techniques in our laboratory (photo-crystallography, ultrafast optical spectroscopy…) and also large facilities (X-FEL, synchrotron, …).

X-ray diffraction


The scientific issues deal with understanding and controlling switching between multi-stable states, in particular driven by light. The new field of photoinduced phase transitions deals with the study and the control of material’s response to light excitation. Indeed, light excitation, of continuous or pulsed nature, may induce the transformation materials towards another phase of different electronic/structural order. This new way of acting on matter combines many of today’s interconnecting issues such as far away from equilibrium phenomena, coherence and quantum control, correlated behaviour and nonlinear responsiveness, interconversion of energy and information, … These are key elements for the advent of control science, where the challenge is not only to observe matter on ever smaller scale but also to direct its functionality at the relevant length, time and energy scales. Our knowledge in the study of complex materials or ordering phenomena is a strong input in the study of multi-stability.

Structural analysis and photo-crystallography

Ultrafast diffraction


Femtosecond pump-probe experiment: ultrafast photo-switching

Femtosecond laser

Ultrafast crystallography: probing structural reorganization

X-ray diffraction under laser irradiation


Most publications are available on the open archive HAL, in the respect for the policy of the publishers.


138 L. Stoleriu, M. Nishino, S. Miyashita, A. Stancu, R. Bertoni, E. Collet, M. Lorenc and C. Enachescu
Multiscale out-of-equilibrium dynamics driven by pulsed laser excitation in spin-crossover materials: a thermo-mechano-elastic study
      Physical Review B (2023)

137 R. Díaz-Torres, G. Chastanet, E. Collet, E. Trzop, P. Harding* and D.J. Harding*
Bidirectional photoswitchability in an FeIII spin crossover complex: Symmetry-breaking and solvent effects
      Chemical Science 14, 7185-7191 (2023)

136 Francisco Javier Valverde-Muñoz,* Ricardo Guillermo Torres Ramírez, Abhilash Ulhe, Elzbieta Trzop, Mousumi Dutta, Chinmoy Das, Pradip Chakraborty, and Eric Collet,*
Ferroelastic phase transition and the role of volume strain in the structural trapping of a metastable quenched low-spin high-symmetry phase in [Ru0.35Fe0.65(ptz)6](BF4)2
      Cryst. Eng. Commun. 25, 3588-3597 (2023)

135 Eric Collet*, Giovanni Azzolina, Jelena Jeftić, Marie-Hélène Lemée-Cailleau
Coupled Spin Cross-Over and Ferroelasticity: Revisiting the Prototype [Fe(ptz)6](BF4)2 Material
      Advances in Physics: X 2161936 (2023)

134 G. Privault, J.Y. Mevellec*, M. Lorenc, B. Humbert, E. Janod, N. Daro, G. Chastanet, A. Subedi* and E. Collet*
Symmetry-resolved study of lattice vibration and libration modes in [Fe(phen)2(NCS)2] crystal
       Crystal Growth & Design 22, 5100-5109 (2022)

133 C. Mathonière,* D. Mitcov, E. Koumousi, D. Amorin, P. Dechambenoit, S. Fatima Jafri, P. Sainctavit, C. Cartier dit Moulin, L. Toupet, E. Trzop, E. Collet, M.A. Arrio, A. Rogalev, F. Wilhelmf R. Clérac*
Metal-to-metal electron transfer in a cyanido-bridged square complex followed by X-ray diffraction and absorption techniques
       ChemComm 58, 12098-12101 (2022)

132 S. Zerdane,* M. Hervé, S. Mazerat, L. Catala, R. Alonso-Mori, J. M. Glownia, S. Song, M. Levantino, T. Mallah,* M. Cammarata,* and E. Collet*
Out-of-equilibrium dynamics driven by photoinduced charge transfer in CsCoFe PBA nanocrystals
       Faraday Discussion 237, 224-236 (2022)

131 A. Volte, C. Mariette, R. Bertoni, M. Cammarata, X. Dong, E. Trzop, H. Cailleau, E. Collet, M. Levantino, M. Wulff, J. Kubicki, F. Yang, M.L. Boillot, B. Corraze, L. Stoleriu, C. Enachescu, M. Lorenc
Dynamical limits for the molecular switching in a photoexcited material revealed by X-ray diffraction
Communications Physics 5, 168 (2022)

130 Lucas Gournay, Ievgeniia Chaban, Jean-Yves Mevellec,* Bernard Humbert, Etienne Janod, Laurent Guerin, Marco Cammarata, Nathalie Daro, Guillaume Chastanet,* Eric Collet*
Shifting photo-stationary light-induced excited spin state trapping equilibrium towards higher temperature by increasing light fluence
      Chem. Phys. Letters 791, 139395 (2022)

129 Guénolé Huitric,   Michael Rodriguez-Fano,   Lucas Gournay,   Nicolas Godin,   Marius Herve,   Gaël Privault,   Julien Tranchant,   Zohra Khaldi,   Marco Cammarata,   Eric Collet,   Etienne Janod  and  Christophe ODIN
Impact of the TeraHertz and Optical pump penetration depths on generated strain waves temporal profiles in a V2O3 thin film.
    Faraday Discussion  237, 389-405 (2022)

128 V. Jakobsen, E. Trzop, E. Dobbelaar, L. Gavin, S. Chikara, X. Ding, M. Lee, K. Esien, H. Müller-Bunz, S. Felton, E. Collet, M. Carpenter, V. Zapf, G. Morgan
Domain Wall Dynamics in a Ferroelastic Spin Crossover Complex with Giant Magnetoelectric Coupling
Journal of the American Chemical Society (2021)

127 Emiel Dobbelaar, Vibe B. Jakobsen, Elzbieta Trzop, Minseong Lee, Shalinee Chikara, Xiaxin Ding, Helge Müller-Bunz, Kane Esien, Solveig Felton, Michael A. Carpenter, Eric Collet*, Grace G. Morgan*, Vivien Zapf*
Thermal and Magnetic Field Switching in a Two-Step Hysteretic Mn(III) Spin Crossover Compound Coupled to Symmetry Breakings
     Angewandte Chemie Int Ed. 67, e202114021 (2021)

126 M. Cammarata,* S. Zerdane, L. Balducci, G. Azzolina, S. Mazerat, C. Exertier, M. Trabuco, M. Levantino, R. Alonso-Mori, J. M. Glownia, S. Song, L. Catala, T. Mallah , S. F. Matar, E. Collet*
Charge-transfer driven by ultrafast spin-transition in a CoFe Prussian blue analogue
Nature Chemistry 13, 10-14 (2021) Link to HAL

125  G. Azzolina, H. Tokoro*, K. Imoto, M. Yoshikiyo, S. Ohkoshi* and E. Collet*
Exploring ultrafast photoswitching pathways in RbMnFe Prussian Blue Analogue
Angewandte Chemie Int. Ed. 60, 232267-23273 (2021)

124  G. Azzolina, R. Bertoni, C. Mariette, M. Cammarata, E. Trzop, C. Ecolivet, M. Sander, M. Levantino, H. Tokoro*, K. Imoto, M. Yoshikiyo, S. Ohkoshi* and E. Collet*
Out-of-equilibrium lattice response to photo-induced charge-transfer in a MnFe Prussian blue analogue
Journal of Materials Chemistry C 9, 6773-6780 (2021)

123 Eric Collet and Giovanni Azzolina
Coupling and decoupling of spin crossover and ferroelastic distortion: Unsymmetric hysteresis loop, phase diagram, and sequence of phases
Physical Review Materials 5, 044401 (2021)

122 C. Mariette,* M. Lorenc,* H. Cailleau, E. Collet, L. Guérin, A. Volte, E. Trzop, R. Bertoni, X. Dong, B. Lépine, O Hernandez, E. Janod, L. Cario, V. Ta Phuoc, S. Ohkoshi, H. Tokoro, L. Patthey, A. Babic, I. Usov, D. Ozerov, L. Sala, S. Ebner, P. Böhler, A Keller, A. Oggenfuss, T. Zmofing, S. Redford, S. Vetter, R. Follath, P. Juranic, A. Schreiber, P. Beaud, V. Esposito, Y Deng, G. Ingold, M. Chergui, G. F. Mancini, R. Mankowsky, C. Svetina, S. Zerdane, A. Mozzanica, M. Wulff, M. Levantino, H. Lemke, M. Cammarata*
Strain Wave Pathway to Semiconductor-to-Metal Transition Revealed by Time-Resolved X-ray Powder Diffraction
Nature Communication 12 1239 (2021) Open Access

121 Giovanni Azzolina, Roman Bertoni, and Eric Collet*
General Landau theory of non-symmetry-breaking and symmetry-breaking spin transition materials
Journal of Applied Physics 129, 085106 (2021) Link to HAL

120 Eric Collet, Sylvain Ravy
Ultrafast Phenomena in condensed matter physics
C.R. Physique (2021)

119 L. Piñeiro-López, F.-J. Valverde-Muñoz, E. Trzop, M. C. Muñoz, M. Seredyuk, J. Castells-Gil, I. da Silva, C. Martí-Gastaldo, E. Collet,* J.A. Real*
Guest Induced Reversible ON-OFF Switching of Elastic Frustration in a 3D Spin Crossover Coordination Polymer with Room Temperature Hysteretic Behaviour
Chemical Science 12, 1317 (2021) Open Access

118 V.B. Jakobsen, S. Chikara, J.-X. Yu, E. Dobbelaar, C. T. Kelly, X. Ding, F. Weickert, E. Trzop, E. Collet,
H.-P. Cheng, G. G. Morgan*, V. S. Zapf*
Giant Magnetoelectric Coupling and Magnetic Field-Induced Permanent Switching in a Spin Crossover Mn(III) Complex
Inorganic Chemistry (2020) Link to HAL

117 G. Azzolina, R. Bertoni, C. Ecolivet, H. Tokoro, S. Ohkoshi, and E.Collet*
Landau theory for non-symmetry-breaking electronic instability coupled to symmetry-breaking order parameter applied to Prussian blue analog
Physical Review B 102, 134104 (2020) Link to HAL

116 L. Trinh, S. Zerdane, S. Mazérat, D. Dragoe, C. Herrero, E. Riviere, L. Catala, M.Cammarata, E. Collet, T. Mallah*
Photo-Switchable 11 nm CsCoFe Prussian Blue Analogue Nanocrystals with High Relaxation Temperature
      Inorganic Chemistry 59, 18, 13153-13161 (2020) Link to HAL

115 R. Kulmaczewski, E. Trzop, E. Collet,* S. Velac,* and M. A. Halcrow,*
Structure:Function Relationships for Thermal and Light-Induced SCO in Isomorphous Molecular Materials
      Journal of Materials Chemistry C, 8 8420 (2020) Link to HAL

114 E. Collet*
News & Views
Ultrafast control of anisotropy
      Nature Chemistry 12, 429 (2020) Link to HAL

113 V.B. Jakobsen, E. Trzop, L. C. Gavin, E. Dobbelaar, S. Chikara, X. Ding, K. Esien, H. Müller-Bunz, S. Felton, V. S. Zapf, E. Collet,* M. A. Carpenter,* G. Morgan*
Strain-induced Domain Wall Motion in a Ferroelastic Mn3+ Spin Crossover Complex
      Angewandte Chemie International Edition doi 10.1002/anie.202003041 (2020) Link to HAL

112 C. Mariette,* E. Trzop, J.-Y. Mevellec, A. Boucekkine, A. Ghoufi, G. Maurin, E. Collet, M.C. Muñoz, J.A. Real, B. Toudic
Symmetry breakings in a metal organic framework with a confined guest
      Phys. Rev. B 101 134103 (2020) Link to HAL

111 M. Hojorat, H. Al Sabea, L. Norel,* K. Bernot,* T. Roisnel, F. Gendron, B. Le Guennic, E. Trzop, E. Collet, J.R. Long, S. Rigaut
Photomodulation via Single-Crystal-to-Single-Crystal Isomerization of a Photochromic Chain of Dysprosium Single-Molecule Magnets
      J. Am. Chem. Soc. doi 10.1021/jacs.9b10584 (2020) Link to HAL

110 S. Zerdane, M. Cammarata,* O. Iasco, M.-L. Boillot, and E. Collet*
Photoselective MLCT to d-d pathways for light-induced excited spin state trapping
      The Journal of Chemical Physics 10.1063/1.5127507 (2019) Link to HAL

109 T. Boonprab, S.G. Telfer, S. J. Lee, K. S. Murray, W. Phonsri, G. Chastanet, E. Collet, E. Trzop, P. Harding,* D.J. Harding*
First observation of hidden hysteresis in an Fe(III) spin crossover complex
      Angewandte Chemie International Edition, 58 11811-11815 (2019)

108 S. Ohkoshi,* H. Tokoro,* E. Collet*
Thermally- and photo-induced phase transitions in rubidium manganese hexacyanoferrate combining charge-transfer and structural reorganization
      Compte Rendus Chimie, 22 498-507 (2019)

107 K. Ridier, A. Bas, V. Shalabaeva, W. Nicolazzi, L. Salmon, G. Molnár,* A. Bousseksou, M. Lorenc,* R. Bertoni, E. Collet, H. Cailleau
Finite size effects on the switching dynamics of spin-crossover thin films photoexcited by a femtosecond laser pulse
      Advanced Materials 1901361 (2019)

106 E. Collet*, G. Azzolina, T. Ichii, L. Guerin, R.Bertoni, A. Moréac, M. Cammarata, N. Daro, G. Chastanet, J. Kubicki, K. Tanaka, S. F. Matar
Lattice phonon modes of the spin crossover crystal [Fe(phen)2(NCS)2] studied by THz, IR, Raman spectroscopies and DFT calculations
      Europrean Journal of Physics B, 92, 12 (2019)
A full-text view-only version of the paper is available here: Link to HAL

105 Roman Bertoni,* Eric Collet, Hervé Cailleau, Marie-Laure Boillot, Antoine Tissot, Jérôme Laisney, Cristian Enachescuc, Maciej Lorenc*
Temperature dependence of the cooperative out-of-equilibrium elastic switching in a spin-crossover material
      Physical Chemistry Chemical Physics 21 6606 (2019) Link to HAL

104 G. Azzolina, E. Collet*, C. Mariette, M. Cammarata, E. Trzop, M. Sander, M. Levantino, K. Nakagawa, H. Tokoro, S. Ohkoshi, R. Bertoni*
Single laser shot photoinduced phase transition of rubidium manganese hexacyanoferrate investigated by X-ray diffraction
Selected by the Editorial Office as Very Important Paper
      European Journal of Inorganic Chemistry 27, 3142-3147 (2019) Link to HAL

103 E. Collet*, M. Cammarata*
by the Editorial Office for our Showcase of outstanding Review-type articles
Concept article: Disentangling ultrafast electronic and structural dynamics with X-ray lasers
      Chemistry: a European Journal 24, 15696-15705 (2018) Link to HAL

102 S. Xue, Y. Guo, A. Rotaru, H. Müller-Bunz, G. G. Morgan, E. Trzop, E. Collet, J. Olah, Y. Garcia
Spin crossover behaviour in a homologous series of iron(II) complexes based on functionalized-bipyridyl ligands
      Inorganic Chemistry 57, 9880-9891 (2018) Link to HAL

101 A. Djemel, O. Stefanczyk, M. Marchivie, E. Trzop, E. Collet, C. Desplanches, R. Delimi, G. Chastanet
Hot paper!
Solvatomorphism-Induced 45 K Hysteresis Width in a Spin Crossover Mononuclear Compound
      Chemistry: a European Journal 24, 14760-14767 (2018) Link to HAL

100 K. A. Zenere, S. G. Duyker, E. Trzop, E. Collet, B. Chan, P.W. Doheny, C. J. Kepert and S. M. Neville*
Increasing spin crossover cooperativity in 2D Hofmann-type materials with guest molecule removal
      Chemical Science 9, 5623-5629 (2018) Link to HAL

99 O.Jeannin, E. W. Reinheimer, P. Foury-Leylekian, J.-P. Pouget, P. Auban-Senzier, E. Trzop, E. Collet, M. Fourmigue
Decoupling anion-ordering and spin-Peierls transitions in a strongly one-dimensional organic conductor with a chessboard structure, (o-Me2TTF)2NO3
IUCr Journal 5, 361–372 (2018) Link to HAL

98 S. Zerdane, E. Collet,* X. Dong, S. F. Matar, H. F. Wang, C. Desplanches, G. Chastanet, M. Chollet, J. M. Glownia, H.T. Lemke, M. Lorenc, M. Cammarata,*
Electronic and structural dynamics during the switching of the photomagnetic complex [Fe(L222N5)(CN)2]
Chemistry A European Journal 24, 5064-5069 (2018)
Link to HAL

97 E. Collet, P. Guionneau
Structural analysis of spin-crossover materials: From molecules to materials
Comptes Rendu Chimie Académie des Sciences 21, 1133-1151 (2018) OPEN ACCESS

96 S. Zerdane, M. Cammarata,* L. Balducci, R. Bertoni, L. Catala, S. Mazerat, T. Mallah, M. N. Pedersen, M. Wulff, K. Nakagawa, H.Tokoro, S. Ohkoshi, E. Collet,*
Probing transient photoinduced charge-transfer in Prussian Blue Analogues with time-resolved XANES and optical spectroscopy
European Journal of Inorganic Chemistry 272-277 (2018)
Link to HAL

95 M. Chergui* and E. Collet*
Photoinduced structural dynamics of molecular systems mapped by time-resolved x-ray methods.
Thematic Issue 2017 Ultrafast Processes in Chemistry
Chemical Reviews, 117 (16), 11025–11065 (2017) Link to HAL

94 S. Zerdane, L. Wilbraham, M. Cammarata,* O. Iasco, E. Rivière, M.-L. Boillot, I. Ciofini, and E. Collet*
Comparison of structural dynamics and coherence of d-d and MLCT light-induced spin state trapping
Chemical Science 8, 4978-4986 (2017) OPEN ACCESS

93 R.Kulmaczewski, E.Trzop, L.J. Kershaw Cook, E.Collet,* G.Chastanet* and M.A. Halcrow*
The role of symmetry breaking in the structural trapping of light-induced excited spin states
Chemical Communication 53, 13268 (2017)
Link to HAL

92 H. T. Lemke*, K. S. Kjær, R. Hartsock, T. B. van Driel, M. Chollet, J. M. Glownia, S. Song, D. Zhu, E. Pace, S. F. Matar, M. M Nielsen, M. Benfatto, K. J. Gaffney, E. Collet, Marco Cammarata*
Coherent structural trapping through wave packet dispersion during photoinduced spin state switching
Nature Communication, 8, 15342 (2017) OPEN ACCESS

91 Y. Jiang, L. Chung Liu, H. M. Müller-Werkmeister, C. Lu, D. Zhang, R. L. Field, A. Sarracini, G. Moriena, E. Collet, R. J. D. Miller*
Structural Dynamics upon Photoexcitation in a Spin Crossover Crystal probed with Femtosecond Electron Diffraction
Angewandte Chemie International Edition 56, 7130-7134 (2017) Link to HAL

90 T. Parpiiev, M. Servol, M. Lorenc, I. Chaban, R. Lefort, E. Collet, H. Cailleau, P. Ruello, N. Daro, G. Chastanet, T. Pezeril.
Ultrafast non-thermal laser excitation of gigahertz longitudinal and shear acoustic waves in spin-crossover molecular crystals [Fe(PM-AzA)2(NCS)2
Applied Physics Letters (2017)
Link to HAL

89 I. Jeon, C. Mathoniere, R. Clerac, M. Rouzieres, O. Jeannin, E. Trzop, E. Collet and M. Fourmigue
Photoinduced reversible spin-state switching of an FeIII Complex assisted by a halogen-bonded supramolecular network
Chemical Communications doi 10.1039/C7CC03797J (2017)
Link to HAL

88 C. Enachescu*, L. Stoleriu, M. Nishino, S. Miyashita, A. Stancu, M. Lorenc, R. Bertoni, H. Cailleau, E. Collet
A theoretical approach for elastically driven cooperative switching of spin crossover compounds impacted by an ultrashot laser pulse
Physical Review B 95, 224107 (2017) Link to HAL

87 M. Buron-Le Cointe, E. Collet, B. Toudic, P. Czarnecki, H. Cailleau*
Back to the Structural and Dynamical Properties of Neutral-Ionic Phase Transitions
Crystals 7, 285 (2017). OPEN ACCESS

86 C. Mariette, E. Trzop, S. Zerdane, P. Fertey, D. Zhang, F.J. Valverde-Munoz, J.A. Real, E. Collet*
Formation of local spin-state concentration waves during the relaxation from photoinduced state in a spin-crossover polymer
Acta Crystallographica B, 73 660-667 (2017).
Link to HAL

85 Daopeng Zhang, Elzbieta Trzop, Francisco J. Valverde-Muñoz, Lucía Piñeiro-López, M. Carmen Muñoz, Eric Collet,* and José A. Real*
Competing phases involving spin-state and ligand structural orderings in a multistable two-dimensional spin crossover coordination polymer
Crystal Growth & Design, 17, 2736-2745 (2017) Link to HAL

84 R. Bertoni, M. Lorenc*, H. Cailleau, A. Tissot, J. Laisney, M.-L. Boillot, L. Stoleriu, A. Stancu, C. Enachescu, E. Collet*.
Elastically driven cooperative response of a molecular material impacted by a laser pulse
Nature Materials 15, 606-610 (2016)
Link to HAL

83 E. Trzop, D. Zhang, L. Piñeiro-Lopez, F.J. Valverde-Muñoz, M. C. Muñoz, L. Palatinus, L. Guerin, H. Cailleau, J. A. Real and E. Collet*
Hot paper!
First step towards Devil’s Staircase in Spin Crossover materials

Angewandte Chemie Int. Ed. 55, 8675–8679 (2016) Link to HAL

82 R. Bertoni, M. Lorenc, T. Graber, R. Henning, K. Moffat, J.-F. Létard, and E. Collet*
Cooperative elastic switching vs laser heating in [Fe(phen)2(NCS)2] spin-crossover crystals excited by a laser pulse

Cryst.Eng.Comm. 18, 7269-7275 (2016) Link to HAL

81 H. Watanabe, K. Tanaka, N. Bréfuel, H. Cailleau, J.-F. Létard, S. Ravy, P. Fertey, M. Nishino, S. Miyashita, and E. Collet*.
Ordering phenomena of high-spin/low-spin states in stepwise spin-crossover materials described by the ANNNI model.

Phys. Rev. B 93 014419 (2016) Link to HAL

80 E. Collet*, L. Henry, L. Piñeiro-López, L. Toupet and J.A. Real
Single Laser Shot Spin State Switching of [FeII(Py)Pt(CN)4] Inside Thermal Hysteresis studied by x-ray diffraction

Current inorganic Chemistry, 6, 61-66 (2016) OPEN ACCESS

79 A. Marino, M. Cammarata, S.F. Matar, J.-F. Létard, G. Chastanet, H. T. Lemke, E. Collet*.
Activation of coherent lattice phonon following ultrafast molecular spin-state photo-switching: a molecule-to-lattice energy transfer

Structural Dynamics 3, 023605 (2016)

78 A. J. Fitzpatrick, E. Trzop, H. Müller-Bunz, M. M. Dîrtu, Y. Garcia, E. Collet* and G. G. Morgan*.
Electronic vs Structural Ordering in a Manganese(III) Spin Crossover Complex
Chem Comm. DOI: 10.1039/c5cc05129k (2015)

77 M. Servol, N. Moisan, E. Collet, H. Cailleau, W. Kaszub, L. Toupet, D. Boschetto, T. Ishikawa, A. Moréac, S. Koshihara, M. Maesato, M. Uruichi, X. Shao, Y. Nakano, H. Yamochi, G. Saito, M. Lorenc
Local response to light excitation in the charge-ordered phase of (EDO-TTF)2SbF6
Phys. Rev. B 024304 (2015)

76 R. Bertoni, M. Lorenc, J. Laisney, A. Tissot,A. Moréac, S.F. Matar, M. L. Boillot, E. Collet*
Femtosecond spin-state photo-switching dynamics in an FeIII spin crossover solid accompanied by coherent structural vibrations
J. Mat. Chem. C 3, 7792-7801 (2015)

75 K. Drużbicki, J. Mielcarek, A. Kiwilsza, L. Toupet, E. Collet, A. Pajzderska, J. Wasicki.
Computationally Assisted (Solid-State DFT) Structural (X-Ray) and Vibrational Spectroscopy(FT-IR, FT-RS, TDs-THz) Characterization of the Cardiovascular Drug – Lacidipine
Crystal Growth & Design 15, 2817-2830 (2015)

74 R. Bertoni, M. Cammarata, M. Lorenc, S. Matar, J.F. Létard, H. Lemke, E. Collet*.
Ultrafast Light-Induced Spin-State Trapping Photophysics Investigated in Fe(phen)2(NCS)2 Spin-Crossover Crystal
Accounts of Chemical Research 48, 774-781 (2015)

73 A. Marino, M. Buron-Le Cointe*, M. Lorenc, L. Toupet, R. Henning, A.D. DiChiara, K. Moffat, N. Brufel, E. Collet*
Out-of-equilibrium dynamics of photoexcited spin-state concentration waves
Faraday Discussion 177, 363-379 (2015).

72 R. Bertoni, M. Lorenc*, A. Tissot, M.-L. Boillot & E. Collet*
Femtosecond photoswitching dynamics and microsecond thermal conversion driven by laser heating in FeIII spin-crossover solids

Coord. Chem. Rev. 282-283 66-76 (2015)

71 M. Cammarata, R. Bertoni, M. Lorenc, H. Cailleau, S. Di Matteo, C. Mauriac, J.F. Létard, S. Matar, H. Lemke, M. Chollet, S. Ravy, C. Laulhé, E. Collet*.
Sequential activation of molecular breathing and bending during spin-crossover photoswitching revealed with femtosecond optical and x-ray absorption spectroscopy
Physical Review Letters 113 , 227402 (2014)

70 W. Kaszub, A. Marino, M. Lorenc, E. Collet*, E.G. Bagryanskaya, E.V. Tretyakov, V.I. Ovcharenko, M.V. Fedin
Ultrafast photoswitching in copper-nitroxide based molecular magnet
Ang. Chem. Int. Ed 53, 10636 –10640 (2014).

69 A. Marino, P. Chakraborty, M. Servol, M. Lorenc, E. Collet, A. Hauser
The role of ligand-field states in the ultrafast photophysical cycle of the prototypical iron(II) spin-crossover compound [Fe(ptz)6](BF4)2
Ang. Chem. Int. Ed 53, 3863-3867(2014).

68 K.D. Murnaghan, C. Carbonera, L. Toupet, M. Griffin, M.M. Ditru, C. Desplanches, Y. Garcia, E. Collet, J.F. Létard, G. Morgan
Spin state ordering on one Sub-lattice of a Mononuclear Iron(III) Spin Crossover Complex exhibiting LIESST and TIESST
Chemistry: A European Journal 20, 5613-5618(2014)

67 A. Tissot, E. Rivière, R. Guillot, L. Toupet, M.L. Boillot.
Light-Induced Excited Spin State Trapping effect on [Fe(mepy)3tren](PF6)2 solvated crystals.
Dalton Transaction 43, 1063-1071 (2014).

66 F. Camerel, G. Le Helloco, T. Guizouarn, O. Jeannin, M. Fourmigue, A. Frackowiak, I. Olejniczak, R. Swietlik, A. Marino, L. Toupet, E. Collet, P. Auban-Senzier, E. Canadell
Correlation between Metal–Insulator Transition and Hydrogen-Bonding Network in the Organic Metal δ-(BEDT-TTF)4[2,6-Anthracene-bis(sulfonate)]·(H2O)4
Crystal Growth & Design, 13 (11) 5135–5145 (2013)

65 B. Siwick & E. Collet
Molecular motion watched
News & Views Nature, 496, 306 (2013)

64 H. Cailleau, M. Lorenc, M. Buron-Le Cointe, M. Servol, M. Cammarata, E.Collet
Impacting materials by light and seeing their structural dynamics
Eur.Phys.J.SpecialTopics 222, 1077–1092 (2013)

63 A. Marino, M. Servol, R. Bertoni, M. Lorenc, C. Mauriac, J.-F. Létard, E. Collet
Femtosecond optical pump-probe reflectivity studies of spin-state photo-switching in the spincrossover molecular crystals [Fe(PM-AzA)2(NCS)2]
Polyhedron 66, 123-128 (2013)

62 A. Tissot, H. J. Shepherd, L. Toupet, E. Collet, J. Sainton, G. Molnár, P. Guionneau, M.-L. Boillot*
Temperature and pressure-induced switching of the molecular spin states of the orthorhombic [(TPA)Fe(TCC)]SbF6 spin-crossover salt.
Eur. J Inorg. Chem. 5-6, 1001-1008 (2013)

61 W. Kaszub, M. Buron-Le Cointe, M. Lorenc, M.-L. Boillot, M. Servol, A. Tissot, L. Guérin, H. Cailleau, E. Collet*
Spin-state photoswitching dynamics of the [(TPA)Fe(TCC)]SbF6 complex
Eur. J Inorg. Chem 5-6, 992-1000 (2013)

60 H. Watanabe, N. Bréfuel, E. Collet, L. Toupet, K. Tanaka, J.-P. Tuchagues*
Symmetry breaking versus spin crossover during the thermal pathway and the out-of-equilibrium relaxation dynamics in the [FeH2L2-Me](ClO4)2 complex
Eur. J Inorg. Chem. 5-6, 710-715 (2013)

59 E. Collet, H. Watanabe, N. Bréfuel, L. Palatinus, L. Roudaut, L. Toupet, K. Tanaka, J.-P. Tuchagues, P. Fertey, S. Ravy, B. Toudic, H. Cailleau
Aperiodic spin state ordering of bi-stable molecules and its photoinduced erasing
Phys. Rev. Lett. 109, 257206 (2012)

58 P. Czarnecki, A. Pajzderska, E. Collet, L. Toupet, J. Wasicki,
New Ferroelectric: Bis-Thiourea Pyridinium Bromide Inclusion Compound
Journal of Materials Research, 27 2844-2850 (2012).

57 R. Bertoni, M. Lorenc*, A. Tissot, M. Servol, M.-L. Boillot & E. Collet*
Femtosecond spin-state photo-switching of molecular nanocrystals evidenced by optical spectroscopy
Ang. Chem. Int. Ed 51, 7485 –7489 (2012).

56 E. Collet*, M. Lorenc, M. Cammarata, L. Guérin, M. Servol, A. Tissot, M.L. Boillot,H. Cailleau, M. Buron
100 picosecond diffraction catches structural transients of laser-pulse triggered switching in a spin-crossover crystal
Chemistry: A European Journal 18, 2051-2055 (2012)

55 E. Collet*, N. Moisan, C. Baldé, R. Bertoni, E. Trzop, C. Laulhé, M. Lorenc, M. Servol, H. Cailleau, A. Tissot, M.L. Boillot, T. Graber, R. Henning, P. Coppens and M. Buron
Ultrafast spin-state photoswitching in a crystal and slower consecutive processes investigated by femtosecond optical spectroscopy and picosecond X-ray diffraction
Phys. Chem. Chem. Phys. 14, 6192-6199 (2012)

54 M. Buron-Le Cointe, J. Hébert, C. Baldé, N. Moisan1, L. Toupet, P. Guionneau, J.F. Létard, E. Freysz, H. Cailleau, E. Collet*
Intermolecular control of thermo- and photo-switching phenomena in two spin-crossover polymorphs
Phys. Rev. B. 85, 85, 064114 (2012)

53 M. Lorenc, Ch. Balde, W. Kaszub, A. Tissot, N. Moisan, M. Servol, M. Buron-Le Cointe, H. Cailleau, P. Chasle, P. Czarnecki, M. L. Boillot, E. Collet
Cascading photo-, elasto- and thermo-switching of spin-state triggered by a femtosecond laser pulse in an Fe(III) molecular crystal
Phys. Rev. B. 85, 054302 (2012)

52 C. D’Amico, M. Lorenc, E. Collet, K. Green, K. Costuas, O. Mongin, M. Blanchard-Desce, and F. Paul*,
Probing Charge Transfer Excited States in a Quasi Non-Luminescent Electron-Rich Fe(II)-Acetylide Complex by Femtosecond Optical Spectroscopy
Journal of Physical Chemistry C116, 3719-3727 (2012)

51 H. Cailleau, T. Luty, S. Koshihara, M. Servol, M. Lorenc, M. Buron-Le Cointe,E. Collet.
PIPT from the Beginning to Future
Acta Physica Polonica A, 121, 297-306 (2012)

50 Y. Okimoto, T. Miyata, M.S. Endo, M. Kurashima, K. Onda, T. Ishikawa, S. Koshihara, M. Lorenc, E. Collet, H. Cailleau, and T. Arima
Ultrafast spectral weight transfer in RBaCo2O6δ (R=Sm, Gd, and Tb): A role of electronic correlation in photoinduced phase transition
Physical Review B, 84, 121102 (2011)

49 A. Tissot, R. Bertoni, E. Collet, L. Toupet, M.L. Boillot
The cooperative spin-state transition of an iron(III) compound [FeIII(3-MeO-SalEen)2]PF6: thermal- vs ultra-fast photo-switching
Journal of Materials Chemistry, 35, 2333-2340 (2011)

48 H. Watanabe, H. Hirori, S. Mouri, N. Bréfuel, J.P. Tuchagues, E. Collet, K. Tanaka
Dynamical separation of the coupled order parameters in the relaxation process from the photo-induced state
Europhysics Letters, 96 17004 (2011).

47 C. Laulhé, S. Ravy, P. Fertey, E. Elkaim, F. Legrand, P. Féret, Ph. Hollander, S. Hustache, M. Bordessoule, J.-P. Ricaud, E. Collet, M. Lorenc, M. Buron- Le Cointe, H. Cailleau, A. Tissot, M.-L. Boillot
"Time-resolved pump-probe diffraction experiment at SOLEIL synchrotron: photoinduced spin transition in the molecular crystal [TPA Fe(III) TCC] PF6".
Acta Physica Polinica A, special issue 121, 332 (2012)

46 W. Kaszub, E. Collet, H. Cailleau, M. Servol, M-L. Boillot, A. Tissot, M. Lorenc
" White light snapshot of non-equilibrium high spin state in a molecular crystal "
Acta Physica Polinica A, special issue, 121, 324 (2012)

45 F. Varret, A. Slimani, K. Boukheddaden, C. Chong, H. Mishra, E. Collet, J. Haasnoot, S. Pillet
"The propagation of the thermal spin transition of Fe(btr)2(NCS) 2].H2O single crystals, observed by optical microscopy."

New journal of Chemistry, 35, 2333–2340 (2011)

44 O.J. Hernandez, C. Tassel, K. Nakano, W. Paulus, C. Ritter, E. Collet, A. Kitada, K. Yoshimurac, H. Kageyama

"First single-crystal synthesis and low temperature structural determination of the quasi-2D quantum spin compound (CuCl)LaNb2O7"
Dalton Transactions, 40 4605-4613 (2011).

43 C. Chong, F. Varret,K. Boukheddaden, E. Collet, J.C. Ameline, R. Bronisz, A. Hauser
"The stepwise temporal evolution of the thermal spin transition in [Fe(bbtr)3](ClO4)2 single crystals explained by optical microscopy in terms of inhomogeneous stresses".
Chem. Phys. Lett. 504 29-33 (2011)

42 L. Guérin, J. Hébert, M. Buron-Le Cointe, S. Adachi, S. Koshihara, H. Cailleau, Eric Collet*.
"Capturing one-dimensional precursors of a photoinduced transformation in a material",
Phys. Rev. Lett.105, 246101 (2010).

41 C. Tassel,J. Kang,C. Lee,O. Hernandez,Y. Qiu,W. Paulus,E. Collet,B. Lake,T. Guidi,M.-H. Whangbo,C. Ritter,H. Kageyama,and S.-H. Lee*
"Ferromagnetically coupled Shastry-Sutherland quantum spin singlets in (CuCl)LaNb2O7",
Phys. Rev. Lett.105, 167205 (2010).

40 E. Collet "Dynamical structural science"
Acta Cryst. A. 66, 133-134 (2010).

39 N. Bréfuel, E. Collet*, H. Watanabe, M. Kojima, N. Matsumoto, L. Toupet, K. Tanaka, J.P. Tuchagues*
"Nanoscale self-hosting of molecular spin states in the intermediate phase of spin-crossover materials"
Chem. Eur. J. 16 14060-14068 (2010).

38 H. Svendsen, J. Overgaard, M. Chevallier, E. Collet, Y. Chen, F. Jensen, B.B. Iversen*,
"Photomagnetic switching of heterometallic complexes, M1(DMF)4(H2O)3(µ-CN)Fe(CN)5H2O, M1 = Nd, La, Gd, Y, analyzed by single crystal X-ray diffraction and ab initio theory"
Chem. Eur. J. 16, 7215-7226 (2010).

37 C. Chong, H. Mishra, K. Boukheddaden, S. Denise, G. Bouchez, E. Collet, J.C. Ameiline,A. Naik, Y. Garcia, F. Varret*,
" Electronic and Structural Aspects of Spin Transitions observed by Optical Microscopy. The case of [Fe(ptz)6](BF4)2"
J. Phys. Chem. B 114, 1975-1984 (2010).

36 H. Cailleau, M. Lorenc, L. Guérin, M. Servol, E. Collet, M. Buron-Le Cointe
"Structural dynamics of photoinduced molecular switching in the solid state"

Acta Cryst. A. 66, 189-197 (2010).

35 N. Bréfuel*, H. Watanabe, L. Toupet, J. Come, M. Kojima, N. Matsumoto, E. Collet*,
K. Tanaka, J.P. Tuchagues* "Concerted Spin Crossover and Symmetry Breaking Yield three Thermally- and one Light-Induced Crystallographic Phases of a Novel Molecular Material"

Ang. Chem. Int. Ed 48, 9304-9307 (2009).

34 M. Lorenc, J. Hébert, N. Moisan, E. Trzop, M. Servol, M., Buron,H. Cailleau, M.L. Boillot, E. Ponte, M. Wulff, S. Koshihara, E. Collet*
"Successive dynamical steps of photoinduced switching of a molecular Fe(III) spin-crossover material by time-resolved x-ray diffraction",
Phys. Rev. Lett. 103, 028301 (2009).

33 T. Ishikawa, N. Fukazawa,Y. Matsubara, R. Nakajima, K. Onda, Y. Okimoto, S. Koshihara, M. Lorenc,E. Collet, M. Tamura* and R. Kato
Large and ultrafast photoinduced reflectivity change in the charge separated phase of in Et2Me2Sb[Pd(dmit)2]2
Physical Review B 80, 115108 (2009).

32 . E. Collet,* M.L. Boillot, J. Hebert, N.Moisan, M. Servol, M. Lorenc, L. Toupet, M. Buron-Le Cointe, A. Tissot, J. Sainton
" Polymorphism in the spin-crossover ferric complex [(TPA)Fe(III)(TCC)] PF6",
Acta Cryst. B 65, 474-480 (2009).

31 H. Svendsen, J. Overgaard, M. Chevallier, E. Collet, B.B. Iversen*
"Single crystal X-ray diffraction study of the excited state structure of photo-magnetic complex, Nd(DMF)4(H2O)3(µ-CN)Fe(CN)5∙ H2O "
Ang. Chem. Int. Ed. 48, 2780-2783(2009).

30 A. Pajzderska*, E. Collet, P. Czarnecki, J. Wąsicki
" Ferroelectricity of inclusion compounds of thiourea with pyridinium iodide and nitrate "
J. Phys. Chem. C 113, 6282-6289(2009).

29 A. Pajzderska*, J. Wąsicki, P. Czarnecki, L. Toupet, E. Collet
"Discovery of an intermediate phase in bis-thiourea pyridinium chloride inclusion compound "
J. Chem. Phys. 130, 044503. (2009).

28 T.Ishikawa*, N. Fukazawa, Y. Matsubara, R. Nakajima, K. Onda, Y. Okimoto, S. Koshihara, M. Tamura, R. Kato, M. Lorenc, E. Collet
"The photo-induced phase transition in Et2Me2Sb[Pd(dmit)2]2"
Phys. Stat. Sol.(c) 1,112-115 (2009).

27 B. Toudic*, P. Garcia, C. Odin, P. Rabiller, C. Ecolivet, E. Collet, P. Bourges, G.J. Mc Intyre, M.D. Hollingsworth, T. Breczewski.
"Hidden degrees of freedom in aperiodic materials"
Science 316, 69-71 (2008).

26 D. Glijer, J. Hebert, E. Trzop, E. Collet, L. Toupet, H. Cailleau, , G.S. Matouzenko, H.Z. Lazar J.-F. Létard, S. Koshihara, M. Buron-Le Cointe*.
"Photoinduced phenomena and structural analysis associated with the spin state switching in the [Fe(DPEA)(NCS)2] complex"
Physical Review B, 78,134112 (2008).

25 A. Pajzderska*, J. Wąsicki, H. Małuszyńska, P. Czarnecki, L. Toupet, E. Collet
"Structural and dynamical aspects of the phase transition in the new thiourea thiazolium Br inclusion compound"
J. Chem. Phys., 129, 104501 (2008).

24N. Moisan, M. Servol, M. Lorenc, A. Tissot, M.L. Boillot, H. Cailleau, S. Koshihara, E. Collet*
"Towards ultrafast photoinduced spin state switching in molecular solids",
Comptes Rendus Chime Académie des Sciences 11, 1235-1240 (2008).

23 Eric Collet*, Maciej Lorenc, Marylise Buron, Hervé Cailleau
" State of the art and opportunities in probing photoinduced phase transitions in molecular materials by conventional and picosecond X-ray diffraction".
Zeitschrift fuer Kristallographie 223, 272-282 (2008).

22 V. Mishra, R. Mukherjee, J. Linares, François Varret, J. F. Létard, E. Collet, M.Castro
“Narrow hysteresis and spin transition properties of [FeII(L6)2][ClO4]2.C7H8 investigated by magnetic, structural, calorimetric and spectroscopic means”
Inorg. Chem 47, 7577-7587 (2008).

21 A. Goujon, F. Varret*, K. Boukheddaden, C. Chong, J Jeftic, Y. Garcia, A. D. Naik, J.C. Amelineand E. Collet
"An optical microscope study of photo-switching and relaxation in single crystals of the spin transition solid [Fe(ptz)6](BF4)2, with image processing"
Inorganica Chimica Acta, 361, 4055-4064 (2008).

20 S. Nozawa*, S. Adachi,J. Takahashi, R. Tazaki, L. Guérin, M. Daimon,A. Tomita,T. Sato, M. Chollet, E. Collet, H. Cailleau, S. Yamamoto, K. Tsuchiya, T. Shioya, H. Sasaki, T. Mori, K. Ichiyanagi, H. Sawa, H. Kawatab and S. Koshihara.
"Developing 100-picosecond resolved X-ray structural analysis capabilities at the NW14A, Photon Factory Advanced Ring"
Journal of Synchrotron Radiation 14, 313–319 (2007).

19 M.H. Lemée-Cailleau*, E. Collet, M. Buron-Le Cointe, N. Grach, B. Ouladdiaf, F. Moussa, T. Hasegawa, Y. Takahashi, T. Roisnel, H. Cailleau
"Down to the quantum limit at the Neutral-to-Ionic phase transition of
(BEDT-TTF)-(ClMe-TCNQ) – Symmetry analysis and phase diagram"

J. Phys. Chem. B, 111 (22), 6167-6172 (2007).

18 N. Ould Moussa, E. Trzop, S. Zein, G. Molnar, E. Collet*, M. Buron, J.A. Real*, S. Borshch, K. Tanaka, H. Cailleau, A. Bousseksou*,
"Wavelength Selective Photomagnetic Phenomena in the Dinuclear Spin
Crossover Compound {[Fe(bt)(NCS)2]2(bpym)}
Physical Review B, 75 054101(2007).

17 E. Trzop, M. Buron-Le Cointe,H. Cailleau,L. Toupet, G. Molnar,A. Bousseksou, A. B.Gaspar,J. A. Real*andE.Collet*
"Structural Investigation of the Photoinduced Spin Conversion in the Binuclear Compound {[Fe(bt)(NCS)2](bpm)}:Toward Multi-stepped Molecular Switches.",
Journal of Applied Crystallography 40, 158-164 (2007).

16 M. Buron-Le Cointe, MH Lemée-Cailleau, H. Cailleau, S. Ravy, JF Bérar, S. Rouzière, E. Elkaim, E. Collet
"1D Fluctuating Nanodomains in the C-T Molecular System TTF-CA and their First-Order Crystallization"
Physical Review Letters, 96 205503 (2006).

15K. Ichiyanagi*, J. Hebert, L. Toupet, H. Cailleau, E. Collet*, P. Guionneau, J.F. Létard,
"Structural investigation of the photoinduced spin transition in the [Fe(PM-BiA)2(NCS)2] compound".
Solid State Phenomena, 112, 81-88(2006).

14K. Ichiyanagi, J. Hebert, L. Toupet, H. Cailleau, P. Guionneau, J.F. Létard, E. Collet*.
"Cooperative photoinduced spin transition in [Fe(PM-BiA)2(NCS)2] driven by a domain nucleation process".
Rapid communication, Physical Review B, 73 060408(R) (2006).

13 E. Collet*, M. Buron-Le Cointe, H. Cailleau
"Photoinduced structural transition probed by time-resolved X-ray in electron-lattice and electron-spin
interacting system".
Journal of the Physical Society of Japan, 75(1), 011002 (2006).

12 M. Buron-Le Cointe*, E. Collet, L. Guérin, M.H. Lemée-Cailleau, H. Cailleau, M. Wulff, T. Luty, S. Koshihara, K. Tanaka,
"Time-resolved X-ray diffraction: a wonderful tool for probing structural photoinduced phase transitions."