EPR and magnetic susceptibility of technetiUm binuclear clusters with metal-metal multiple bond

Technetium clusters in which binuclear fragment Tcsub(2)sup(n+) has uneven charge n=5 have been studied. The problem of the nature of paramagnetism and multiplicity of Tc-Tc bond in the complexes is considered. Magnetic properties of polycrystal samples of the compounds (NH4)3Tc2Cl8x2H2O, Tc2(CH3COO)4Cl, Tc2(CD3COO)4Cl, KTC2-(CH3COO)4Cl2 and Tc2(CH3COO)4Br have been studied using the Faraday method at the temperatures 80-300 K in magnetic fields of the intensity 5-10 kOe. It is shown that paramagnetism of the compounds with the fragment Tc25+ is caused by one non-coupled electron per two technetiUm atoms. This electron is located on bsub(1u)-MO, mainly formed by 4dsub(xy)-AO of two technetium atoms, which is of deltasub(M-M)-charac-- ter. The results testify to the fact that in all the compounds considered the multiplicity of Tc-Tc bond constitutes 3.5