Theoretical analysis of isoelectronic octahedral xenon and cesium oxyanions

The method of Xsub(α)-scattered waves (Xsub(L) SW SSP) has been used to calculate electronic structures for isoelectron octahedral XeO64- and CsO63- anions. The anions are shown to have identical electron structures both in undercutting of disposition of molecular orbitals and in their composition. MO composition reveals that chemical bond in both anions has similar character, it is the result of interaction of 2s- and 2p-oxygen orbitals with 5s- and 5p- xenon or cesium orbitals. Closeness of energy values and MO composition of XeO64- and CsO63- anions as well as charges on xenon and cesium atoms point out that these anions should not essentially differ by bond energies. A conclusion on a possibility of existing relatively stable salts of Na3CsO6 type in the solid state is made