Article
Chemistry, Multidisciplinary
Veronica Jornet-Molla, Carlos Gimenez-Saiz, Dmitry S. Yufit, Judith A. K. Howard, Francisco M. Romero
Summary: The spin crossover salt [Fe(bpp)(2)](isonicNO)(2). 2.4 H2O undergoes a very abrupt spin crossover at 274.4 K, with reversible response to light irradiation or temperature change; Isotopic effects in the thermomagnetic behavior highlight the significance of hydrogen bonds in determining the magnetic state; The compound can be reversibly dehydrated to produce 1, which also exhibits spin crossover coupled with H-bond isomerization, resulting in strong kinetic effects in the thermomagnetic properties.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Mario Palacios-Corella, Javier Ramos-Soriano, Manuel Souto, Duarte Ananias, Joaquin Calbo, Enrique Orti, Beatriz M. Illescas, Miguel Clemente-Leon, Nazario Martin, Eugenio Coronado
Summary: This study designed and synthesized a family of hexakis-substituted [60]fullerene adducts with a well-known ligand for spin-crossover systems. Experimental and theoretical evidence showed that these molecular scaffolds can form polynuclear SCO complexes in solution, and retain SCO properties in the solid state.
Article
Chemistry, Inorganic & Nuclear
Cyril Rajnak, Romana Micova, Jan Moncol, Lubor Dlhan, Christoph Krueger, Franz Renz, Roman Boca
Summary: The iron(iii) mononuclear complex [Fe(Cl-3,Cl-5-L)(NCSe)] exhibits a thermally induced spin crossover with a broad hysteresis width, showing different spin states at different temperatures. Analogous complexes of the [Fe(X-3,X-5-L)(Y)] type are high-spin over the whole temperature interval.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Inorganic & Nuclear
Patroula Gkolfi, Dimitra Tsivaka, Ioannis Tsougos, Katerina Vassiou, Ondrej Malina, Michaela Polaskova, Christina D. Polyzou, Christos T. Chasapis, Vassilis Tangoulis
Summary: The reverse micelle method was used to synthesize water-soluble silica hybrid, spin-crossover nanoparticles, showing potential as smart MRI agents based on temperature-dependent T2 values from MRI experiments. Lyophilization of the nanoparticle dispersions in water resulted in powders with preserved but modified thermal hysteretic magnetic profiles.
DALTON TRANSACTIONS
(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
Chemistry, Inorganic & Nuclear
Diego Plaza-Lozano, Agustin Conde-Gallardo, Juan Olguin
Summary: The study investigated the effect of chelate ring size on the magnetic properties of thioether-based iron(II) metal complexes by synthesizing and characterizing two types of ligands. The results showed that the complexes were isolated in the high spin state, with orbital contribution to g and zero field splitting. The analysis of structural and electronic parameters helped rationalize the differing magnetic properties of the metal complexes.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Lee T. Birchall, Amber T. Raja, Lewis Jackson, Helena J. Shepherd
Summary: To improve strategies for spin-crossover material design, obtaining isostructural materials is crucial for developing and understanding structure-property relationships. In this study, we synthesized four isostructural cocrystal solvates using a specific complex and coformer. The spin-crossover properties of these materials were determined by single-crystal X-ray diffraction and were found to be influenced by the hydrogen bond basicity of the anions and solvents present.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Chemistry, Inorganic & Nuclear
Nataliya G. Spitsyna, Maxim A. Blagov, Vladimir A. Lazarenko, Roman D. Svetogorov, Yan Zubavichus, Leokadiya Zorina, Olga Maximova, Sergey A. Yaroslavtsev, Vyacheslav S. Rusakov, Grigory Raganyan, Eduard B. Yagubskii, Alexander N. Vasiliev
Summary: A potassium salt of the N2S2O2-coordination Fe(III) anion has been synthesized, characterized structurally and magnetically, and shown to exhibit a three-step cooperative spin-crossover transition. The study reveals unique phenomena during the spin-crossover process, such as unexpected changes in iron(III)-ligand bond lengths and a structural phase transition in the final step. This research provides a new platform for understanding the multistep spin-crossover character in Fe(III) thsa-complexes and related compounds.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Raul Diaz-Torres, Silvia Gomez-Coca, Eliseo Ruiz, Phimphaka Harding, David J. Harding
Summary: A family of heteroleptic spin crossover (SCO) complexes have been synthesized, and their spin transition properties vary with temperature. The magnetic properties of these complexes are significantly improved by slight changes in crystal packing, which enhance the cooperativity.
DALTON TRANSACTIONS
(2023)
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, Multidisciplinary
Aleksandra Toloczko, Marcin Kazmierczak, Marek Weselski, Milosz Siczek, Maria Ksiazek, Joachim Kusz, Robert Bronisz
Summary: This study observed the reaction between 1,1'-di (tetrazol-1-ylo)methane and iron(II) tetrafluoroborate in the presence of adiponitrile, forming a coordination compound with a three-dimensional network structure. The structural phase transitions of the compound were triggered by temperature changes during cooling and heating processes, which were caused by conformational changes of the adiponitrile molecules.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Chemistry, Inorganic & Nuclear
Shuwen Jia, Lingyue Fan, Chunyang Zheng, Sai Jin, Dongfeng Li
Summary: A series of cyano-bridged mixed-valence hexanuclear complexes were successfully synthesized by building the units in methanol and ethanol solutions. One of the complexes exhibited a single-crystal-to-single-crystal transformation in water. Detailed analysis of the coordination environment and magnetic susceptibility measurements confirmed their spin-crossover properties.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Laia Navarro, Jordi Cirera
Summary: This work presents a systematic study on the ligand design in the anionic spin-crossover system and how it can be used to achieve a high degree of tuning of its transition temperature. Different ligand substitutions and functionalizations allow for a large or fine change in the transition temperature.
INORGANIC CHEMISTRY FRONTIERS
(2022)
Review
Chemistry, Inorganic & Nuclear
Bijoy Dey, Vadapalli Chandrasekhar
Summary: This review focuses on spin crossover phenomena, particularly in Fe-II complexes in the N4O2 coordination environment. It discusses three ligand families: Jager-type ligands, hydrazone-based ligands, and tridentate ligands with salicylaldehyde derivatives. It explores the assembly of mononuclear and multinuclear complexes, as well as the coupling of optical and magnetic properties.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Zhi-Kun Liu, Zi-Shuo Yao, Jun Tao
Summary: Halogen-substituted Fe(III) compounds with different spin states were synthesized, some of which exhibited light-induced excited spin-state trapping effects and reversible light switching behaviors, providing insights for the development of switchable materials.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Sophie Schonfeld, Gerald Horner, Frank W. Heinemann, Anja Hofmann, Roland Marschall, Birgit Weber
Summary: This manuscript presents the solvent-dependent synthesis of 1D coordination polymers and examines the effect of different solvents on the magnetic spin crossover properties of the resulting materials. The results demonstrate that the solvent-of-synthesis plays a crucial role in determining the magnetic behavior of the DMF-derived polymer.
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
(2021)
Article
Chemistry, Inorganic & Nuclear
Christopher Simon, Andre Bloesser, Mirco Eckardt, Hannah Kurz, Birgit Weber, Mirijam Zobel, Roland Marschall
Summary: Phase-pure 6 nm spinel MnFe2O4 nanoparticles with high specific surface area were successfully synthesized via microwave-assisted non-aqueous sol-gel method. The phase evolution during thermal treatment, magnetic properties, and visible-light response of the nanoparticles were systematically studied. The nanoparticles exhibited good dispersibility and potential applications in light-related technologies such as photocatalysis.
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
(2021)
Article
Chemistry, Inorganic & Nuclear
Andreas Duerrmann, Gerald Hoerner, Stefan Wagner, Matthias Breuning, Birgit Weber
Summary: A Schiff base-like ligand with a para-terphenyl backbone was synthesized and converted into an octahedral iron(II) coordination polymer. Characterization of the coordination polymer through magnetic measurements and Mossbauer spectroscopy revealed high spin character.
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
(2021)
Article
Energy & Fuels
Morten Weiss, Gerald Hoerner, Birgit Weber, Roland Marschall
Summary: Tungsten-based defect-pyrochlores CsMxW2-xO6 are used as model oxides to investigate the high number of possible M cations that can be used to form the defect-pyrochlore crystal structure. A large variety of possible compounds are presented, several of which have been unknown so far. These compounds are used in photocatalytic hydrogen evolution to investigate possible correlations between the photocatalytic activity and the varying elemental compositions.
Article
Chemistry, Multidisciplinary
Hannah Kurz, Christian Hils, Jana Timm, Gerald Hoerner, Andreas Greiner, Roland Marschall, Holger Schmalz, Birgit Weber
Summary: Responsive fluorescent materials have great potential for sensing and imaging applications. In this study, a previously reported non-fluorescent zinc(II) complex [Zn(L)] was encapsulated into non-fluorescent polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymer micelles, resulting in brightly emissive materials. The quantum yield of the emission could be easily tuned by selecting the solvent, and a medium-dependent off-on sensor could be established through controlled acidification.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Sebastian Hammon, Mara Klarner, Gerald Horner, Birgit Weber, Martin Friedrich, Jurgen Senker, Rhett Kempe, Thiago Branquinho de Queiroz, Stephan Kummel
Summary: Loading with nickel significantly increases the photocatalytic hydrogen evolution rates in a system combining a photosensitizer and metal cluster. Theoretical calculations show that the charge transfer from metal to photosensitizer plays a crucial role in the optical excitations of the system. Additionally, the binding energy between nickel and the photosensitizer is considerably higher than that of palladium and platinum.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Christoph Goebel, Katharina Marquardt, Dirk Baabe, Markus Drechsler, Patrick Loch, Josef Breu, Andreas Greiner, Holger Schmalz, Birgit Weber
Summary: The combination of polymers with nanoparticles allows for the creation of customizable composite materials with additional properties provided by a switchable spin crossover (SCO) core. By controlling the composition of the diblock copolymers and the amount of complex employed, the size and shape of the resulting SCO nanocomposite particles can be controlled. The nanocomposite samples with the highest P4VP content exhibited a morphological transition from spherical nanoparticles to worm-like structures, which can be explained by the impact of complex coordination on the self-assembly of the diblock copolymers.
Article
Chemistry, Physical
Thilini K. Ekanayaka, Hannah Kurz, Kayleigh A. McElveen, Guanhua Hao, Esha Mishra, Alpha T. N'Diaye, Rebecca Y. Lai, Birgit Weber, Peter A. Dowben
Summary: The spin state transition behavior of Fe(ii) spin crossover coordination polymer crystallites at the surface differs from the bulk, possibly due to factors such as oxidation, differences in surface packing, and changes in coordination. Some Fe(ii) spin crossover coordination polymers may be photoactive enough to prevent discernment of the spin state transition using X-ray spectroscopies.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Constantin Schreck, Johannes Weihermueller, Peter Thoma, Sabine Rosenfeldt, Markus Drechsler, Christoph Foerster, Katja Heinze, Gerald Hoerner, Birgit Weber
Summary: The aggregation behavior of an amphiphilic copper(II) complex was studied in solution using UV-Vis and EPR spectroscopy. The results showed that concentrated solutions in nonpolar media exhibited broadening of EPR-lines, which could be associated with the formation of oligomers with weak anti-ferromagnetic coupling. Electron microscopy confirmed the tendency towards supramolecular aggregation, with the formation of extended 2D sheet-like structures and 1D thread-like structures.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
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, 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)
Editorial Material
Chemistry, Multidisciplinary
Malcolm Halcrow, Birgit Weber, Masahiro Yamashita, Sanjit Konar
CRYSTAL GROWTH & DESIGN
(2023)
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
Materials Science, Multidisciplinary
Thilini K. Ekanayaka, Hannah Kurz, Ashley S. Dale, Guanhua Hao, Aaron Mosey, Esha Mishra, Alpha T. N'Diaye, Ruihua Cheng, Birgit Weber, Peter A. Dowben
Summary: X-ray spectroscopy confirms the spin state transition, but details differ from magnetometry, especially in terms of critical transition temperatures and curve progression. Ising model simulations suggest a transition activation energy around 160 to 175 meV and a nonzero exchange J, indicating potential perturbations to the bistability of spin states.
MATERIALS ADVANCES
(2021)
