The low-temperature EPR spectrum of the cluster magnet CENI

O.V. Kravchyna, A.I. Kaplienko, A.G. Anders

B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine 47 Lenin Ave., Kharkov 61103, Ukraine
E-mail: kravchina@ilt.kharkov.ua

D.A. Chervinskii, Yu.G. Pashkevich

A. Galkin Donetsk Physico-Technical Institute of the National Academy of Sciences of Ukraine 72 R. Luxemburg Str., Donetsk 83114, Ukraine
E-mail: pashkevi@kinetic.ac.donetsk.ua

A. Orendachova and M. Kajnakova

Centre of Low Temperature Physics of the P. J. Šafárik University & the Slovak Academy of Science 9 Park Angelinum, Košice 04154, Slovakia
E-mail: aorendac@kosice.upjs.sk
pos Анотація:

Received Jule 3, 2007

The energy spectrum of the cluster and the resonance transitions in the EPR spectra for the tetramer with exchange interaction of nearest neighbors and diagonal coupling were calculated. The isotropic and anisotropic exchange interactions were analyzed. In the latter case the Dzjaloshynski–Moria interaction was included. The results of calculation can describe the shape of absorption EPR band of the powder sample of the metal-organic compound CENI. The shape of the band changes considerablegy with temperature. It is shown that this changing is the result of additional resonance transitions between energy levels the intensity of which increases with lowering temperature.

PACS: 76.30.–v Electron paramagnetic resonance and relaxation;
PACS: 75.30.Gw Magnetic anisotropy.

Key words: tetramer, EPR, energy spectrum, isotropic and anisotropic exchange interaction.