Ovcharenko Victor, Romanenko Galina, Polushkin Alexey, Letyagin Gleb, Bogomyakov Artem, Fedin Matvey, Maryunina Kseniya, Nishihara Sadafumi, Inoue Katsuya, Petrova Marina, Morozov Vitaly, Zueva Ekaterina
International Tomography Center SB RAS , 3A Institutskaya Street , Novosibirsk 630090 , Russia.
Novosibirsk State University , Pirogova Street 1 , Novosibirsk 630090 , Russia.
Inorg Chem. 2019 Jul 15;58(14):9187-9194. doi: 10.1021/acs.inorgchem.9b00815. Epub 2019 Jun 26.
A study of the single-crystal-to-single-crystal transformation induced by temperature variation for the chain polymer Cu(II) complex with nitronyl nitroxide showed that an increase in the hydrostatic pressure of up to ∼0.07 GPa completely changes the intracrystalline displacements of molecules relative to one another. This, in turn, significantly affects the interaction energy of the unpaired electrons of the paramagnetic centers and hence the form of the temperature dependence of the magnetic susceptibility . The cooling of crystals under normal conditions causes a rearrangement of the intrachain exchange clusters {>N-•O-Cu(II)-O•-N<} accompanied by a shortening of the distances between the paramagnetic centers. This changes the character of exchange interactions and generates multistage spin transitions. An increase in the hydrostatic pressure leads to a drastic change in the O···O distances between the nitroxyl fragments of adjacent chains, an increase in the antiferromagnetic exchange between them, and complete suppression of spin transitions.
