Magnetic Bistability and Single-Crystal-to-Single-Crystal Transformation Induced by Guest Desorption

An iron(II) complex with ferrocenyl groups, [Fe(dppFc)2](BF4)2·2Et2O (1·2Et2O, dppFc = 1-ferrocenyl-2-{(2,6-bis(pyrazolyl)pyridyl}ethylene), was prepared. X-ray crystallographic analyses revealed that 1·2Et2O underwent a single-crystal-to-single-crystal transformation with the release of crystal solvent molecules. In magnetic susceptibility measurements, a reversible conversion between paramagnetism and spin-crossover induced by solvent molecules was observed

Magnetic Bistability and Single-Crystal-to-Single-Crystal Transformation Induced by Guest Desorption

An iron(II) complex with ferrocenyl groups, [Fe(dppFc)2](BF4)2·2Et2O (1·2Et2O, dppFc = 1-ferrocenyl-2-{(2,6-bis(pyrazolyl)pyridyl}ethylene), was prepared. X-ray crystallographic analyses revealed that 1·2Et2O underwent a single-crystal-to-single-crystal transformation with the release of crystal solvent molecules. In magnetic susceptibility measurements, a reversible conversion between paramagnetism and spin-crossover induced by solvent molecules was observed

Magnetic Bistability and Single-Crystal-to-Single-Crystal Transformation Induced by Guest Desorption

An iron(II) complex with ferrocenyl groups, [Fe(dppFc)2](BF4)2·2Et2O (1·2Et2O, dppFc = 1-ferrocenyl-2-{(2,6-bis(pyrazolyl)pyridyl}ethylene), was prepared. X-ray crystallographic analyses revealed that 1·2Et2O underwent a single-crystal-to-single-crystal transformation with the release of crystal solvent molecules. In magnetic susceptibility measurements, a reversible conversion between paramagnetism and spin-crossover induced by solvent molecules was observed

Magnetic Bistability and Single-Crystal-to-Single-Crystal Transformation Induced by Guest Desorption

An iron(II) complex with ferrocenyl groups, [Fe(dppFc)2](BF4)2·2Et2O (1·2Et2O, dppFc = 1-ferrocenyl-2-{(2,6-bis(pyrazolyl)pyridyl}ethylene), was prepared. X-ray crystallographic analyses revealed that 1·2Et2O underwent a single-crystal-to-single-crystal transformation with the release of crystal solvent molecules. In magnetic susceptibility measurements, a reversible conversion between paramagnetism and spin-crossover induced by solvent molecules was observed

Antiferromagnetic Fe^III₆ Ring and Single-Molecule Magnet Mn^II₃Mn^III₄ Wheel

Reactions of a quadridentate ligand [N-(2-hydroxy-5-nitrobenzyl)iminodiethanol] with iron and manganese chloride in methanol yielded an antiferromagnetic FeIII6 ring and a single-molecule magnet MnII3MnIII4 wheel, respectively

Cyanide-Bridged Iron(II,III) Cube with Multistepped Redox Behavior

A building unit of Prussian blue was isolated as a cyanide-bridged iron cube of [FeII4FeIII4(CN)12(tp)8]·12DMF·2Et2O·4H2O [tp− = hydrotris(pyrazolyl)borate]. A cyclic voltammogram showed quasi-reversible four-stepped redox waves, which correspond to [FeIII4FeII4]/[FeIII5FeII3]+, [FeIII5FeII3]+/[FeIII6FeII2]2+, [FeIII6FeII2]2+/[FeIII7FeII1]3+, and [FeIII7FeII1]3+/[FeIII8]4+ processes. Controlled potential absorption spectral measurements revealed two intervalence charge-transfer bands at 816 and 1000 nm, which were assigned to charge transfers from FeII ions to adjacent and remote FeIII ions, respectively, in the cube

Antiferromagnetic Fe^III₆ Ring and Single-Molecule Magnet Mn^II₃Mn^III₄ Wheel

Reactions of a quadridentate ligand [N-(2-hydroxy-5-nitrobenzyl)iminodiethanol] with iron and manganese chloride in methanol yielded an antiferromagnetic FeIII6 ring and a single-molecule magnet MnII3MnIII4 wheel, respectively

Synthesis of Azo-Conjugated Metalladithiolenes and Their Photo- and Proton-Responsive Isomerization Reactions

A versatile synthetic method of azo-conjugated metalladithiolenes was developed, and new complexes with various central metals and substituent groups were synthesized. Molecular structures of the azo-conjugated metalladithiolenes of Ni(II), Pd(II), and Pt(II) with diphenylphosphinoethane as a co-ligand were determined by X-ray crystallography. While the energy of the reversible trans-to-cis photoisomerization is considerably lower than that of azobenzene, the thermal stability of the cis form is much higher than that of the organic azobenzene derivatives showing similar low-energy trans-to-cis photoisomerization. A novel proton response of the azo group occurs, and the combination of photoisomerization and protonation leads to a novel proton-catalyzed cis-to-trans isomerization, the rate of which correlates with the redox potential of the metalladithiolene moiety. The study including other azo-conjugated metalladithiolenes has indicated that the protonation is a common feature for the azo-conjugated metalladithiolenes, but trans-to-cis photoisomerization is strongly dependent on the electronic structure of the trans form or a steric effect in the cis form

Synthesis of Azo-Conjugated Metalladithiolenes and Their Photo- and Proton-Responsive Isomerization Reactions

A versatile synthetic method of azo-conjugated metalladithiolenes was developed, and new complexes with various central metals and substituent groups were synthesized. Molecular structures of the azo-conjugated metalladithiolenes of Ni(II), Pd(II), and Pt(II) with diphenylphosphinoethane as a co-ligand were determined by X-ray crystallography. While the energy of the reversible trans-to-cis photoisomerization is considerably lower than that of azobenzene, the thermal stability of the cis form is much higher than that of the organic azobenzene derivatives showing similar low-energy trans-to-cis photoisomerization. A novel proton response of the azo group occurs, and the combination of photoisomerization and protonation leads to a novel proton-catalyzed cis-to-trans isomerization, the rate of which correlates with the redox potential of the metalladithiolene moiety. The study including other azo-conjugated metalladithiolenes has indicated that the protonation is a common feature for the azo-conjugated metalladithiolenes, but trans-to-cis photoisomerization is strongly dependent on the electronic structure of the trans form or a steric effect in the cis form

Synthesis of Azo-Conjugated Metalladithiolenes and Their Photo- and Proton-Responsive Isomerization Reactions

A versatile synthetic method of azo-conjugated metalladithiolenes was developed, and new complexes with various central metals and substituent groups were synthesized. Molecular structures of the azo-conjugated metalladithiolenes of Ni(II), Pd(II), and Pt(II) with diphenylphosphinoethane as a co-ligand were determined by X-ray crystallography. While the energy of the reversible trans-to-cis photoisomerization is considerably lower than that of azobenzene, the thermal stability of the cis form is much higher than that of the organic azobenzene derivatives showing similar low-energy trans-to-cis photoisomerization. A novel proton response of the azo group occurs, and the combination of photoisomerization and protonation leads to a novel proton-catalyzed cis-to-trans isomerization, the rate of which correlates with the redox potential of the metalladithiolene moiety. The study including other azo-conjugated metalladithiolenes has indicated that the protonation is a common feature for the azo-conjugated metalladithiolenes, but trans-to-cis photoisomerization is strongly dependent on the electronic structure of the trans form or a steric effect in the cis form