抄録
At four microwave frequency bands (λ=78, 10, 16 and 32 mm), single crystals of copper acetate monohydrate, Cu(CH3COO)2H2O, were examined at room temperature by the method of paramagnetic resonance absorption, the results differing somewhat from those of usual copper salts. They can be explained by a spin-Hamiltonian with an effective spin S=1 which is considered to be originated from a pair of Cu++ ions each in 2D state, holding a strong interaction between them. This is consistent with the results of X-ray crystallography; this crystal consists of bimolecular units Cu2(CH3COO)4·2H2O, in which two copper ions approach as close as 2.64 Å. Exchange energy between these copper ions in the unit was estimated using the parameters determined from the resonance spectra and its temperature dependence is discussed.
