| Autor: |
Voronkova, V. K., Mosina, L. V., Yablokov, Yu.V., Kovácik, I., Langfelderová, H., Kozisek, J. |
| Zdroj: |
Molecular Physics; April 1992, Vol. 75 Issue: 6 p1275-1284, 10p |
| Abstrakt: |
Electron paramagnetic resonance (EPR) of single-crystal [Cu(PU)5(ClO4)2]2, built of dimeric fragments with P[image omitted] symmetry, Z = 1, and ClO4 anions, was studied over a range of temperatures at both X and Q band frequencies. EPR spectra show the presence of exchange interaction J(S1 · S2) (J < 0) between two identical Cu2+ ions (S1 = S2 = 1/2) in the dimeric fragment. The single-crystal spectra recorded in three different planes were analysed by diagonalization of the full Hamiltonian matrix. The values of g and D were found to have coincident y axes, with the x and z axes rotated by 45°. The tensor of the dipole-dipole interaction was calculated. Two variants for the anisotropic exchange interaction tensor were determined. The data obtained from the analysis of the single-crystal spectra were used to simulate the polycrystalline spectrum. The peculiarities of the polycrystalline spectra for centres S = 1 with nonparallel g and D tensors and the possibilities of their unambiguous interpretation are discussed. The double-quantum transition in single-crystal and polycrystalline spectra was detected. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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