Paramagnetic resonance, local symmetry and lability of paramagnetic centers structure in A2M(ZrF6)2 · 6H2O type compounds, activated by bivalent manganese ions

In the temperature range of 300-4.2 K at the frequencies of X- and Q-ranges ESR spectra of Mn2+ impurity centres in monoclinic crystals A2Zn1-xMnx(ZrF6) · 6H2O (1) with A = K+, Rb+, NH1-x, Cs+ (x = 0.01; 0.1) have been investigated. It is shown that the change in the sign of Mn2+ D parameter in series 1 from A = K+, Rb to A = NH4+, Cs+ is caused by the difference in the character of main distortions of complexes (Mn(H2O)6)2+ in two reciptocally-orthogonal direction of metal-oxygen bonds. The dominating effect of the nature of the impurity ion it self on the configuration and spatial orientation of paramagnetic aquacomplexes in 1 as compared with the effect of A matrix cations is pointed out