Review
Chemistry, Multidisciplinary
Esther Resines-Urien, Estefania Fernandez-Bartolome, Ana Martinez-Martinez, Arturo Gamonal, Lucia Pineiro-Lopez, Jose Sanchez Costa
Summary: Coordination complexes based on transition metal ions with [Ar]3d(4)-3d(7) electronic configurations can undergo a remarkable switchable phenomenon known as Spin Crossover (SCO). SCO is a detectable, reproducible, and reversible switch between the high spin (HS) and low spin (LS) electronic states of the transition metal, induced by various stimuli. This review presents a comprehensive compilation of iron coordination compounds that exhibit color change due to the interaction between the compounds and vapor analytes, coupled with a spin transition at room temperature.
CHEMICAL SOCIETY REVIEWS
(2023)
Article
Chemistry, Physical
Dongzhe Li, Yongfeng Tong, Kaushik Bairagi, Massine Kelai, Yannick J. Dappe, Jerome Lagoute, Yann Girard, Sylvie Rousset, Vincent Repain, Cyrille Barreteau, Mads Brandbyge, Alexander Smogunov, Amandine Bellec
Summary: In this study, a pronounced negative differential resistance (NDR) was observed in spin-crossover (SCO) molecular devices through low-temperature scanning tunneling microscopy (STM) and spectroscopy. The NDR was found to be robust with respect to various factors, indicating its intrinsic relation to the electronic structure of the SCO molecule.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Biochemistry & Molecular Biology
Amila M. Abeysekera, Abhijeet S. Sinha, Christer B. Aakeroy
Summary: Strategies for co-crystal synthesis typically involve hydrogen- or halogen-bond interactions, but predicting the structural influence of both simultaneously can be challenging. Experimental co-crystallization of aliphatic dicarboxylic acids with various target molecules revealed that the structural impact of halogen atoms increases with size, with the abilities of Cl < Br < I in forming sigma-holes.
Article
Chemistry, Multidisciplinary
Liang Zhao, Yin-Shan Meng, Qiang Liu, Osamu Sato, Quan Shi, Hiroki Oshio, Tao Liu
Summary: The study reports a magnetic bistable material consisting of specific compounds that can undergo multiple magnetic states transitions induced by light, showing behaviors of single-chain magnets and single-molecule magnets.
Review
Chemistry, Inorganic & Nuclear
Min Wang, Zhao-Yang Li, Ryuta Ishikawa, Masahiro Yamashita
Summary: Research on multifunctional molecular materials with both magnetic bistability and electrical conductivity has expanded in the last two decades, providing materials with practical application prospects. This review presents recent progress on spin crossover and valence tautomerism conductors, focusing on syntheses, strategies, crystal structures, magnetic properties, and conductivities of such materials, as well as the synergistic and cooperative properties of bistability and conductivity.
COORDINATION CHEMISTRY REVIEWS
(2021)
Review
Chemistry, Multidisciplinary
Ramon Torres-Cavanillas, Miguel Gavara-Edo, Eugenio Coronado
Summary: The field of spin-crossover complexes is transitioning from studying the spin transition phenomenon to its application in molecular electronics. Processing spin-crossover materials as nanoparticles is a convenient way to maintain the bistability and reduce size. This paper reviews the recent advances in the chemical design of these nanoparticles and their integration into electronic devices, while also focusing on integrating them with 2D materials to improve device endurance and spin state detection.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Angel Albavera-Mata, Richard G. Hennig, S. B. Trickey
Summary: We discuss the challenges in calculating transition temperatures for spin-crossover materials and the effects of including the adiabatic crossover energy difference and entropic contributions in the calculations. We show that using the PBE density functional approximation provides comparable results to the more sophisticated r2SCAN approximation, making it suitable for high-throughput materials screening.
JOURNAL OF PHYSICAL CHEMISTRY A
(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
Lorenzo Marchi, Simone Fantuzzi, Andrea Cingolani, Alessandro Messori, Rita Mazzoni, Stefano Zacchini, Marina Cocchi, Luca Rigamonti
Summary: Iron(ii) bis-pyrazolilpyridyl (bpp-R) complexes [Fe(bpp-R)(2)](X)(2)·solvent undergo spin transition from high spin (S = 2, HS) to low spin (S = 0, LS) in the solid state, known as spin crossover (SCO). The distortion of the octahedral coordination environment is affected by crystal packing and modulates the SCO behavior. This study used a multivariate approach combining Principal Component Analysis and Partial Least Squares regression to analyze the structural data of HS structures and efficiently model and predict the spin transition temperature T-1/2 for complexes with different R groups, X- anions, and co-crystallized solvents.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Qianqian Yang, Yin-Shan Meng, Tao Liu, Jinkui Tang
Summary: The study of two iron(o) complexes reveals that the spin states and spin-crossover behavior are influenced by supramolecular interactions and crystal packing effects. Complex 1·ClO4 shows light-induced excited spin state trapping and two-step spin-crossover at room temperature, while complex 1·BF4 exhibits gradual spin-crossover behavior. Magnetostructural analysis provides insight into the differences in the spin-crossover properties of the two complexes.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Jia Wang, Ming Kong, Xiao-Jiao Song, Yu Jing, Yue Zhao, You Song
Summary: Researchers designed and synthesized a strong fluorescent tetradentate pyridine ligand, TPDP. By reacting with Fe(NCX)(2) (X = S and Se) units, two new 2D square-grid compounds were obtained, both of which exhibited expected one-step spin-crossover (SCO) properties. One of the compounds also demonstrated a combination of SCO phenomenon and fluorescence in a synergetic way. The energy transfer mechanism of this compound was verified through theoretical calculations and experimental results. This study provides an effective strategy to synthesize large conjugated fluorescent ligands and further form SCO-luminescent bifunctional materials.
INORGANIC CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Roger Sanchis-Gual, Ramon Torres-Cavanillas, Marc Coronado-Puchau, Monica Gimenez-Marques, Eugenio Coronado
Summary: In this study, core@shell nanoparticles composed of a metallic Au nanostar core and a spin-crossover shell based on the coordination polymer [Fe(Htrz)(2)(trz)](BF4) were designed. The photothermal effect arising from the plasmonic properties of the Au nanostar allowed for a thermal spin transition of 60% of iron centers triggered by low intensity irradiation from a 808 nm laser within a thermal hysteresis. The nanostar shape's advantage lies in the hot spots at the branches, which generate significant near-infrared absorptions.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
David Nieto-Castro, Felipe A. Garces-Pineda, Andrea Moneo-Corcuera, Irene Sanchez-Molina, Jose Ramon Galan-Mascaros
Summary: Bistable multifunctional materials have great potential in various devices, but the direct use of spin crossover materials in electronic devices is limited. Incorporating SCO spin crossover materials as probes in conducting organic polymer matrices can lead to low-resistance conductors with memory effect.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Mamadou Ndiaye, Kamel Boukheddaden
Summary: This theoretical study investigates the effect of pressure on spin-crossover phenomena using an electro-elastic description and a Monte Carlo technique. The results demonstrate that a wide range of experimental observations, including conventional pressure effects, unconventional behaviors, re-entrant transitions, and double step transitions, can be qualitatively described by this model.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Jiajia Li, Xiao-Peng Sun, Shiqi Bi, Minglu Xu, Siyu Jia, Zheng Tang, Pengtao Ma, Jingping Wang, Jun Tao, Jingyang Niu
Summary: This study successfully integrated polyoxometalate (POM) anions into the Fe(II) spin crossover (SCO) system and found that POM anions play an effective role in regulating spin-state switching properties.
INORGANIC CHEMISTRY
(2022)
Article
Nanoscience & Nanotechnology
Leontin Padurariu, Nadejda Horchidan, Cristina Elena Ciomaga, Lavinia Petronela Curecheriu, Vlad Alexandru Lukacs, Radu Stefan Stirbu, George Stoian, Mihaela Botea, Mihaela Florea, Valentin Adrian Maraloiu, Lucian Pintilie, Aurelian Rotaru, Liliana Mitoseriu
Summary: This paper investigates the effect of ferroelectric filler size and clustering on the dielectric properties of 20%BaTiO3-80%PVDF and 20%(2%Ag-98%BaTiO3)-PVDF hybrid nanocomposites. Finite element calculations reveal that fillers with epsilon > 103 do not enhance the permittivity in the composites, and the effective dielectric constant saturates to specific values determined by filler size and clustering. Addition of metallic ultrafine nanoparticles (Ag) increases the permittivity, especially when they are well connected to the ferroelectric particles' surfaces. Experimental dielectric analysis confirms the trends predicted by simulations, with slightly higher permittivity values likely due to changes in polymer phase composition and local inhomogeneity caused by nanofillers and clustering.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Inorganic & Nuclear
P. -. A. Soderstrom, D. L. Balabanski, R. S. Ban, Gh. Ciocan, M. Cuciuc, A. Dhal, V. Fugaru, V. Iancu, A. Rotaru, A. B. Serban, A. State, D. Testov, G. V. Turturica, V. Vasilca
Summary: We have developed and built a high-energy gamma-ray source for the purpose of detector characterisation and calibration. The source consists of a composite structure, with a plutonium-beryllium neutron emitter embedded in a paraffin moderator that is mixed with nickel powder. This 9 MeV gamma-ray source emits approximately 450 photons per second in 4 pi, when 2.2 x 10(5) neutrons per second are emitted, resulting in a surface flux of 9 MeV gamma-rays of about 2.5 x 10(-6) cm(-2) per emitted neutron. In this paper, we discuss the properties and design of this source, including the characterization of homogeneity and the high-energy gamma-ray emission spectra.
APPLIED RADIATION AND ISOTOPES
(2023)
Article
Chemistry, Multidisciplinary
Andreas Duerrmann, Gerald Hoerner, Birgit Weber
Summary: In this study, the solid-state spin crossover properties of three iron(II) complexes were investigated. It was found that subtle adjustments in the outer sphere of the chelate ring resulted in different spin crossover profiles.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Chemistry, Physical
Laura Mihai, Gabriel Caruntu, Aurelian Rotaru, Daniela Caruntu, Vasyl Mykhailovych, Cristina Elena Ciomaga, Nadejda Horchidan, Andrei Stancalie, Aurelian Marcu
Summary: BaTiO3 (BTO) nanoparticles were incorporated into various flexible materials for the fabrication of flexible electronic devices. The dielectric properties of these materials were tested using time domain spectroscopy in the frequency range of 30 GHz-2 THz. The dielectric performances of different materials with varying nanoparticle concentrations (up to 40 wt.%) embedded in gelatin, epoxy, and styrene-butadiene were compared at temperatures ranging from 0 degrees C to 120 degrees C. Optimal nanoparticle concentrations were found to be matrix-dependent, with the best composite performances achieved by the BTO-SBS matrix (2 wt.% filler concentration) and the BTO-gelatin matrix (40 wt.% filler concentration).
Article
Chemistry, Multidisciplinary
Li Sun, Nour El Islam Belmouri, Mamadou Ndiaye, Koen Robeyns, Aurelian Rotaru, Kamel Boukheddaden, Yann Garcia
Summary: In this study, two types of 3D porous coordination polymers were synthesized and characterized. These polymers exhibited different magnetic and optical properties during the cooling process. In addition, the cavities in these porous polymers could accommodate chloroform or dichloromethane molecules, further altering the material's properties. These materials have the potential to be used as reusable storage for chemical and gas sensors.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Chemistry, Analytical
Michael F. Fink, Sophie Schoenfeld, Constantin Schreck, Gerald Hoerner, Birgit Weber
Summary: Electrochemistry and its analytics play a crucial role in various scientific and technological fields, especially in studying properties related to reduction-oxidation reactions. However, there is still a lack of established methodological standards for cryo-electrochemistry at sub-zero temperatures. In this study, a reliable cryo-electrochemical setup was developed, allowing for accurate experiments at temperatures as low as -80°C. The setup combines stable temperature conditioning with gas-tight sealing of the electrochemical cell, and validation experiments demonstrated its reliability.
Article
Chemistry, Inorganic & Nuclear
Henrika M. Hueppe, Linda Iffland-Muehlhaus, Joshua Heck, Maverick Eilers, Hans Gildenast, Sophie Schoenfeld, Andreas Duerrmann, Alexander Hoffmann, Birgit Weber, Ulf-Peter Apfel, Sonja Herres-Pawlis
Summary: This study presents a synthesis route for tri(quinolin-8yl)amine (L), a member of the tetradentate tris(2-pyridylmethyl)amine (TPA) ligand family. The coordination environment of the [Fe(L)]2+ complex and the spin state can be controlled by changing the coligands. The study sheds light on the coligand competition of triflate and acetonitrile and provides insights into the influence of different coligands on the geometry and spin state of the complexes.
INORGANIC CHEMISTRY
(2023)
Article
Polymer Science
Florina-Daniela Cojocaru, Ioannis Gardikiotis, Gianina Dodi, Aurelian Rotaru, Vera Balan, Elena Rezus, Liliana Verestiuc
Summary: The increasing tendency of population aging is directly correlated with a significant number of associated pathologies. Implantable bone substitutes have proven to be an efficient solution for metabolic bone diseases such as osteoporosis or chronic kidney disease-mineral and bone disorders. This study aimed to develop composite beads with a combination of biopolymers (specifically alginate and guar gum/carboxymethyl guar gum) and ceramics (specifically calcium phosphates). The results showed that the beads based on a higher concentration of guar gum had superior properties for bone tissue repair.
Editorial Material
Chemistry, Multidisciplinary
Malcolm Halcrow, Birgit Weber, Masahiro Yamashita, Sanjit Konar
CRYSTAL GROWTH & DESIGN
(2023)
Article
Biochemistry & Molecular Biology
Youssef Draoui, Smaail Radi, Mohamed El Massaoudi, Yousra Bahjou, Sabir Ouahhoud, Samira Mamri, Marilena Ferbinteanu, Redouane Benabbes, Mariusz Wolff, Koen Robeyns, Yann Garcia
Summary: Four mononuclear complexes were synthesized using a new 1,2,4-triazole ligand and the structures of the complexes were studied in relation to the cooperative effect of hydrogen bonding network and counter anions on the supramolecular formations. These compounds showed favorable antibacterial performances and significant antifungal inhibitory activity.
Article
Polymer Science
Dustin N. N. Jordan, Patrick G. G. Strassburg, Dennis Woschko, Luca M. M. Carrella, Laure P. P. Cuignet, Katharina Eickmeier, Richard Dronskowski, Yann Garcia, Eva Rentschler, Christoph Janiak
Summary: Seven new coordination networks with different structures were synthesized and investigated. The interpenetration of the networks is guided by the coordinated and non-coordinated anions. The role of different anions in the formation of the networks was explored.
Article
Chemistry, Analytical
Vasyl Mykhailovych, Gabriel Caruntu, Adrian Graur, Mariia Mykhailovych, Petro Fochuk, Igor Fodchuk, Gelu-Marius Rotaru, Aurelian Rotaru
Summary: We successfully synthesized dielectric spinel-type ZnCr2O4 nanoparticles with controlled shape by a sol-gel auto-combustion method followed by heat treatment. The morphology of the nanoparticles was systematically studied by FE-SEM, PXRD, and dielectric analysis. It was observed for the first time that the nanoparticles changed from shapeless to truncated octahedrons and eventually pseudo-octahedra with increasing post-synthesis heat treatment temperature. The pseudo-octahedral nanoparticles exhibited the best dielectric performance with a high permittivity of epsilon = 1500 and a low dielectric loss tan delta = 5 x 10(-4) at 1 Hz.
Article
Biochemistry & Molecular Biology
Sebastian W. Schleser, Hindole Ghosh, Gerald Hoerner, Jonathan Seib, Sangita Bhattacharyya, Birgit Weber, Rainer Schobert, Prasad Dandawate, Bernhard Biersack
Summary: Inspired by combretastatin A-4 and N-heterocyclic carbene (NHC) complexes of Au(I), new iodidogold(I)-NHC complexes were synthesized and characterized. The synthesis involved van Leusen imidazole formation, N-alkylation, complexation with Ag2O, transmetalation, and anion exchange. The complexes were characterized by various spectroscopic techniques and one complex's structure was confirmed by X-ray diffraction. Preliminary anticancer screening showed promising activities and apoptosis induction in esophageal adenocarcinoma cells treated with the most promising derivative.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Chemistry, Inorganic & Nuclear
Parastoo Moradi, Ehsan Taheri-Nassaj, Amin Yourdkhani, Vasyl Mykhailovych, Andrei Diaconu, Aurelian Rotaru
Summary: AgNbO3 ceramics were produced using two sintering methods. The reaction-sintered samples showed lower energy loss density and higher energy storage efficiency compared to conventional solid-state sintered samples.
DALTON TRANSACTIONS
(2023)
Article
Materials Science, Multidisciplinary
Weiyang Li, Li Sun, Cuilian Liu, Aurelian Rotaru, Koen Robeyns, Michael L. Singleton, Yann Garcia
Summary: The design and construction of colorimetric ammonia (NH3) sensors with high selectivity, great stability, and short response times at room temperature are crucial for human health and food safety. This study presents a chiral supramolecular FeII4L4 metal-organic cage (MOC-1) that can detect NH3(g) in under 10 seconds at room temperature and was used to monitor food safety on fresh bacon bits at 4 degrees C. The MOC-1 sensor demonstrated superior selectivity among NH3(g) and twelve other analytes, and the sensing mechanism is associated with a high-spin to low-spin transition of the Fe-II ions.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
