EPR Spectra of Some Salts of Bis[η5-1,2-Dicarbollyl]nickeliate(III)(1-) Anion [NiIII (η 5-1,2-B9C2H11)2]?

Some salt-like complexes of the cluster anion Ni^III (η⁵-1,2-B₉C₂H₁₁ )₂]⁻ (NiCb₂]⁻), containing paramagnetic Ni³⁺ ion, with cations Cs⁺, (CH₃)₄N⁺, MnPhen₃]²⁺ (where Phen is 1,10-phenanthroline) are studied by EPR method at 77 K and 300 K. A neutral complex MnPhen₂(NCS₂] is also studied for comparison. The synthesis procedure and X-ray diffraction analysis of MnPhen₃]NiCb₂]₂ complex with paramagnetic ions Mn²⁺ (3d ⁵) and Ni³⁺ (3d ⁷) are described. The EPR data of isostructural complexes MnPhen₃]NiCb₂]₂ and MnPhen₃]CoCb₂]₂ are reported. No exchange or dipole-dipole interaction was observed between two paramagnetic ions (Mn²⁺ and Ni³⁺) simultaneously present in a complex structure. The temperature changes in EPR spectra of solid compounds are caused by rearrangements in the Mn²⁺ surrounding. In the case of a salt with a compact spherical Cs⁺ ion, the local perturbation in a second coordination sphere of NiCb₂]⁻ anion leads to redistribution of the electron density and changes in g-factor.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 6, 2005, pp. 403–414.Original Russian Text Copyright © 2005 by Nadolinny, Polyanskaya, Volkov, Drozdova.