Article
Chemistry, Multidisciplinary
Victor Garcia-Lopez, Niccolo Giaconi, Lorenzo Poggini, Joaquin Calbo, Amelie Juhin, Brunetto Cortigiani, Javier Herrero-Martin, Enrique Orti, Matteo Mannini, Miguel Clemente-Leon, Eugenio Coronado
Summary: The synthesis and characterization of a new Co(II) spin-crossover (SCO) complex based on a 4'-(4-carboxyphenyl)-2,2':6',2''-terpyridine ligand are described. The complex can be successfully grafted on the surface of silver while maintaining the spin-crossover behavior. Various techniques including AFM, MALDI-TOF MS, Raman spectroscopy, and XPS measurements confirmed the formation of a monolayer of intact molecules grafted onto the Ag surface through carboxylate groups. Raman spectroscopy, XPS, and XAS supported by first-principles calculations demonstrated a gradual spin transition of the deposited molecules with temperature, which is unprecedented for a monolayer of molecules directly grafted onto a metallic surface.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
M. Nadeem, Jace Cruddas, Gian Ruzzi, Benjamin J. Powell
Summary: This article introduces a microscopic model combining crystal field theory with intermolecular interactions to explain experimental results of spin-crossover materials. Strategies for designing spin-crossover materials with higher stability temperatures are proposed.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Shiladitya Karmakar, Pradip Chakraborty, Tanusri Saha-Dasgupta
Summary: In this computational study, the light-induced excited spin-state trapping (LIESST) in Fe(ii) spin crossover complexes coordinated by different types of ligands was investigated to elucidate the trend in the low temperature relaxation rate. The results show a nine order of magnitude change in the relaxation rate among the complexes. This trend can be rationalized by considering the change in metal-ligand covalency, which affects the back donation or delocalization of the electrons from the low-lying Fe(ii)-centered molecular orbital to the empty low-lying ligand-centered pi* antibonding molecular orbitals.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Kai-Ping Xie, Ze-Yu Ruan, Xiao-Xian Chen, Jiong Yang, Si-Guo Wu, Zhao-Ping Ni, Ming-Liang Tong
Summary: In this study, a 3D Hofmann-type metal-organic framework with incomplete two-step spin crossover behavior was reported. Photomagnetic measurements revealed a rare bidirectional light-induced excited spin-state trapping effect at low temperature, providing a new approach for designing optomagnetic memory devices.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Inorganic & Nuclear
Patrick J. Desrochers, Ali Abdulrahim, Katherine R. Demaree, Joseph A. Fortner, Jamie D. Freeman, Makenzie Provorse Long, Madison E. Martin, Carlos J. Gomez-Garcia, Nikolay Gerasimchuk
Summary: The optical, structural, and magnetic properties of iron(II,III) sandwich complexes, Fe(Tp ')2n+ (Tp ' = bis(3,5-dimethylpyrazolyl)benzotriazolylborate), are described. The intensely colored FeII(Tp ')2 (orange) and FeIII(Tp ')2+ (purple) show strong MLCT bands. Geometric isomerism for M(Tp ')2 is established crystallographically in the racemate of chiral cis-Fe(Tp ')2. For the first time, paramagnetic 11B NMR describes solution-phase low-spin (LS, S 0) to high-spin (HS, S = 2) crossover behavior in Fe(Tp ')2. Thermochemical parameters for solution-phase SCO of Fe(Tp ')2 demonstrate the endothermic LS to HS conversion and entropic preference of the HS state. Entropy changes for both Fe(Tp ')2 isomers are significantly larger than for the majority of iron scorpionate SCO systems. Solid-state magnetic and thermochemical measurements show cis-Fe(Tp ')2 to be thermally stable up to 520 K, allowing experimental investigation of a solid-state SCO magnetic hysteresis of over 45 K. A large solution vs solid-state SCO difference was observed: cis-Fe(Tp ')2 shows Tc Pe. 270 K (solution) and Tc Pe. 385 K (solid), with the remarkably wide Delta Tc Pe. 115 K; trans-Fe(Tp ')2 shows Tc Pe. 278 K (solution) and Tc Pe. 372 K (solid). Solid-state Tc values are among the highest seen for iron(II) molecular systems. The large solution/solid Delta Tc difference is explained by anchoring intermolecular interactions in the solid state that prevent thermal expansion of the LS iron(II) coordination sphere in its transition to the HS state. DFT calculations, validated against LS cis-Fe(Tp ')2 crystallography and LS to HS SCO thermochemical parameters, demonstrate the role the benzotriazole rings play in its structural and optical properties. The Lewis basicity of M(Tp ')2 is shown with the structural characterization of the air-stable tin(II) adduct [cis-Fe(Tp ')2-SnCl2]; tin(II) coordination does not alter the iron(II) spin state. The Tp ' chelate adds functionality (asymmetry, chirality, chemical reactivity) to the array of iron SCO materials for potential incorporation into nanoscale magnetic switches and spintronic devices.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Yu Zhang, Qianqian Yang, Jingjing Lu, Mei Guo, Xiao-Lei Li, Jinkui Tang
Summary: The study focused on the assembly of molecules exhibiting slow magnetic relaxation and spin crossover behaviors simultaneously at the molecular level. A series of mixed-metal structures containing a versatile Schiff-base ligand were synthesized and characterized, showing slow magnetic relaxation and spin crossover behaviors. Additionally, a new type of 3d-4f structure with these dual functionalities was reported for the first time, providing a novel approach for future research in the field.
INORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Nithin Suryadevara, Ansgar Pausch, Eufemio Moreno-Pineda, Asato Mizuno, Jochen Buerck, Ananya Baksi, Tim Hochdoerffer, Ivan Salitros, Anne S. Ulrich, Manfred M. Kappes, Volker Schuenemann, Wim Klopper, Mario Ruben
Summary: Enantiomerically pure Fe(II) grid complexes were successfully prepared by designing novel chiral ligands, allowing for the fabrication of magneto-chiral molecular devices. The chiral resolution of these complexes enables controlled programmable separation before synthesis. The experimental and calculated CD spectra showed good agreement, confirming the enantiomeric purity of the complexes.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Gleb Denisov, Valentin V. Novikov, Svetlana A. Belova, Alexander Belov, Elizaveta Melnikova, Rinat Aysin, Yan Z. Voloshin, Yulia Nelyubina
Summary: This study presents a novel temperature-induced spin crossover phenomenon in an iron(II) clathrochelate, and investigates how the design of extended-tripodal ligands affects the spin state transition and functionalization, potentially making them effective switchable components for molecular electronics and spintronics.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Nikita Konstantinov, Arthur Tauzin, Ulrich Nguetchuissi Noumbe, Diana Dragoe, Bohdan Kundys, Hicham Majjad, Arnaud Brosseau, Marc Lenertz, Aditya Singh, Stephane Berciaud, Marie-Laure Boillot, Bernard Doudin, Talal Mallah, Jean-Francois Dayen
Summary: This study demonstrates the magneto-opto-electronic properties of a hybrid device consisting of a spin crossover (SCO) thin film deposited on a graphene sensing layer. The electrical detection of light-induced spin transitions in SCO/graphene heterostructures is shown, with the switchable spin state of the molecular film affecting the conductance of the graphene channel. The results also highlight the potential for exploring coupling mechanisms between SCO systems and 2D materials, as well as the use of mixed-dimensional heterostructures for molecular electronics and spintronics.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Chemistry, Physical
Yuwei Shen, Johanna Woodburn, Soraya Bouras, Shan Dai, Iurii Dovgaliuk, Jean-Marc Greneche, Gilles Patriarche, Latevi Max Lawson Daku, Christian Serre, Antoine Tissot
Summary: In this article, a novel strategy for preparing bistable porous nanocrystals is presented, which involves anchoring switchable molecules in the pores of a host matrix through strong host-guest interactions. The loaded nanocrystals, based on a prototypical Fe(III) spin-crossover complex in MOF-808, exhibit a hysteretic thermal spin transition close to room temperature, regardless of the complex loading and the MOF particle size, while maintaining high porosity, making them promising for applications in chemical sensing.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Philipp Stegmann, Alex Gee, Neil T. Kemp, Juergen Koenig
Summary: The study reveals that the two spin-crossover molecules are coupled in a nanojunction device and their interaction is described through statistical analysis and parameter extraction. The time dependence of factorial cumulants is used to analyze the impact of interactions between the two spin-crossover molecules on the switching dynamics.
Article
Materials Science, Multidisciplinary
Houcem Fourati, Mamadou Ndiaye, Mouhamadou Sy, Smail Triki, Guillaume Chastanet, Sebastien Pillet, Kamel Boukheddaden
Summary: The low-temperature photoinduced effects of the spin-crossover [{Fe(2-pytrz)(2)[Pd(CN)(4)]}]center dot 3H(2)O single crystal have been investigated. The results show that the system can be switched from an intermediate HS-LS state to a fully photoinduced LS state by irradiation in the near-infrared region. The study reveals that the LS state reached by light is a hidden stable state of the system until a certain temperature.
Article
Chemistry, Multidisciplinary
Matthew G. Reeves, Elodie Tailleur, Peter A. Wood, Mathieu Marchivie, Guillaume Chastanet, Philippe Guionneau, Simon Parsons
Summary: Crystal packing energy calculations are used to analyze a family of spin crossover complexes, revealing a linear relationship between transition abruptness and changes in intermolecular interaction energy in the crystal structures. Abrupt transitions are associated with significant stabilising and destabilising changes in intermolecular interaction energies. Different classes of SCO complexes exhibit varying trends in relation to transition abruptness.
Review
Chemistry, Inorganic & Nuclear
Mohammad Khurram Javed, Arshia Sulaiman, Masahiro Yamashita, Zhao-Yang Li
Summary: The spin crossover (SCO) phenomenon has made remarkable progress in applications, particularly in materials exhibiting SCO-luminescence synergy. This review aims to provide an overview of the luminescent and magnetic properties of SCO materials, synthesis strategies, and progress made in constructing such materials over the years.
COORDINATION CHEMISTRY REVIEWS
(2022)
Article
Chemistry, Physical
Miguel Gavara-Edo, Francisco Javier Valverde-Munoz, M. Carmen Munoz, Safaa Elidrissi Moubtassim, Francisco Marques-Moros, Javier Herrero-Martin, Kateryna Znovjyak, Maksym Seredyuk, Jose Antonio Real, Eugenio Coronado
Summary: Materials based on spin crossover molecules have attracted significant attention in molecular magnetism. This study presents a novel spin crossover material that can form thermally stable thin films while retaining its molecular bistability.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Amel Zorai, Abdelhafid Souici, Diana Dragoe, Eric Riviere, Salim Ouhenia, Jacqueline Belloni, Mehran Mostafavi
Summary: The radiolytic method was used to synthesize ultrasmall cobalt ferrite nanoparticles with superparamagnetic properties. The properties of these nanoparticles were studied at increasing doses of irradiation. The analysis confirmed the formation of ultra-small cobalt ferrite nanoparticles (6-9 nm) in the cubic spinel structure, and their superparamagnetic properties were revealed through temperature-dependent magnetic measurements.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Ulysse Chazarin, Mahe Lezoualc'h, Jyh-Ping Chou, Woei Wu Pai, Abhishek Karn, Raman Sankar, Cyril C. C. Chacon, Yann Girard, Vincent Repain, Amandine Bellec, Sylvie Rousset, Alexander Smogunov, Yannick J. J. Dappe, Jerome Lagoute
Summary: Alkali atom doping is an efficient method for inducing charge transfer and Fermi level tuning in layered materials. This study demonstrates the surface doping of bulk VSe2 crystal with sodium, which modifies the electronic phase and charge density wave behavior. The unexpected upwards shift in energy of electronic states at the edges of the sodium-intercalated area is explained by a local gating effect caused by local dipoles. This research provides a clear example of the intercalation effect in alkali-intercalated bulk layered materials.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Laura Altenschmidt, Patricia Beaunier, Amelie Bordage, Eric Riviere, Giulia Fornasieri, Anne Bleuzen
Summary: The article presents a method for preparing rare-earth free large-size hard magnets by loading Fe(NO3)(3) salt into ordered mesoporous silica monolith and calcination. The study shows controlled size and distribution of ε-Fe2O3 particles and a linear correlation between particle size and magnetic coercivity.
Article
Chemistry, Physical
Yann Girard, Sarah Benbouabdellah, Outhmane Chahib, Cyril Chacon, Amandine Bellec, Vincent Repain, Jerome Lagoute, Yannick J. Dappe, Cesar Gonzalez, Wei-Bin Su
Summary: The coupling of graphene with cobalt allows for technological advances in spintronics. The study focuses on cobalt intercalation between graphene and a buffer layer, which results in cobalt islands covered by graphene. These islands exhibit distinct shapes and properties, including small atomic islands and flat cobalt nanodots encapsulated by graphene.
Article
Chemistry, Inorganic & Nuclear
Sujit Kamilya, Sakshi Mehta, Mohini Semwal, Rodrigue Lescouezec, Yanling Li, Jiri Pechousek, Varimalla R. Reddy, Eric Riviere, Mathieu Rouzieres, Abhishake Mondal
Summary: This article describes a mixed-valence Fe(II)Fe(III) molecular system that undergoes single-crystal-to-single-crystal transformation with increasing temperature, along with thermo-induced spin-state switching behavior. One of the compounds also exhibits photo-induced spin-state switching.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Amandine Bellec, Massine Kelai, Arthur Tauzin, Anastasia Railean, Vincent Repain, Jerome Lagoute, Yann Girard, Sylvie Rousset, Edwige Otero, Talal Mallah, Marie-Laure Boillot, Cristian Enachescu
Summary: In this study, the photoexcitation of ultrathin films of [FeII((3, 5-(CH3)2Pz)3BH)2] (Pz = pyrazolyl) adsorbed on a special substrate was investigated. The anomalous light-induced spin-state switching was observed for sub-monolayer coverage, while the well-known light-induced excited spin-state trapping effect was recovered for higher coverages. The combination of continuous light excitation and thermal cycling revealed light-induced thermal hysteresis for thicker films and extended thermal conversion over a large temperature range for sub-monolayer coverage. Mechanoelastic simulations showed opposite behaviors in different layers of the films due to intermolecular interactions.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Ashutosh Kumar, David Berardan, Diana Dragoe, Eric Riviere, Tomohiro Takayama, Hidenori Takagi, Nita Dragoe
Summary: This study presents detailed investigations of the structural, magnetic, and electronic transport properties of hole-doped high-entropy rare-earth manganites. The high-entropy samples, synthesized using the solid-state technique, show a change in crystal structure with increasing Sr substitution. A rhombohedral structure exhibits prominent ferromagnetic ordering, originating from the dominant double exchange mechanism. The electrical resistivity of high-entropy samples is larger than those of La1_xSrxMnO3, attributed to the enhanced structural distortion.
MATERIALS TODAY PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Kevin Magra, Jean-Frederic Audibert, Diana Dragoe, Talal Mallah, Fabien Miomandre, Marie-Laure Boillot
Summary: A single layer of CoII-BODIPY dyad complex on transparent ITO electrode was prepared and its photoluminescence intensity can be modulated by applying an electric stimulus. The fluorescence intensity decreases when the cobalt is at the +III oxidation state due to CoIII oxidative quenching of BODIPY emission. The reversible electrical switching of the CoII-BODIPY dyad complex grafted on ITO was investigated.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Anastasia Railean, Massine Kelai, Amandine Bellec, Vincent Repain, Marie-Laure Boillot, Talal Mallah, Laurentiu Stoleriu, Cristian Enachescu
Summary: In this paper, the electronic and mechanical behavior of a single layer of spin crossover molecules self-organized on a substrate is discussed within a mechanoelastic model framework. The main experimental results are reproduced, and it is shown that a simple model with fixed neighbors on the substrate can lead to unphysical situations. To improve the model, every spin crossover molecule is allowed to change its adsorption site on the substrate at any moment. Different densities of sites on the substrate are used to simulate further experimental observations.
Article
Chemistry, Inorganic & Nuclear
Marius Retegan, Sadaf Fatima Jafri, Leonardo Curti, Laurent Lisnard, Edwige Otero, Eric Riviere, Maurits W. Haverkort, Anne Bleuzen, Philippe Sainctavit, Marie-Anne Arrio
Summary: This study investigates the contribution of the orbital magnetic moment to magnetization in a potassium hexacyanoferrate(III) sample using X-ray magnetic circular dichroism and molecular multiconfigurational ab initio calculations. The results demonstrate a significant proportion of the total magnetization attributed to the orbital magnetic moment, which is exceptional for 3d transition metal ions. The study also analyzes the impact of crystal field strength and distortion, pi back-bonding, spin-orbit coupling, and external magnetic induction on the spin and orbital magnetic anisotropies, providing a deeper understanding of these phenomena.
INORGANIC CHEMISTRY
(2023)
