Geometry and bonding in alkali-metal-atom–antimony (AnSb4

Theoretical Investigations of Zintl Anions Analogous to Ozone

“…All possible structures identified for the cluster A 3 Sb 3 will be demonstrated to be stabilized through electron transfer from the alkali to the antimony subsystem by which a Jahn−Teller degeneracy is lifted. This feature constitutes a clear parallel of the present investigations to our previous ones on alkali−antimony systems containing the Sb 4 unit . A similar line of arguments will lead to an ozone analogy of the unit ASb 3 in a spin triplet configuration, with spin transfer instead of charge transfer taking the role of the stabilizing process.…”

“…In a series of ab initio investigations, Sb 4 -based systems with 22, 24, and 26 valence electrons, namely, A 2 Sb 4 , A 4 Sb 4 , and A 6 Sb 4 , have been explored. 8 In these complexes, the T d symmetry of the free Sb 4 cluster is found to flatten out into D 4h symmetry. This structural transition can be shown to proceed as a consequence of Jahn-Teller distortion associated with the transfer of additional electrons to a 20valence-electron tetramer of T d symmetry.…”

“…The Sb 4 unit, however, is very sensitive to changes of its valence electron count of 20. In a series of ab initio investigations, Sb 4 -based systems with 22, 24, and 26 valence electrons, namely, A 2 Sb 4 , A 4 Sb 4 , and A 6 Sb 4 , have been explored …”

“…In the present work, we aim at an understanding of both structural and bonding features of a different class of Sb-based clusters rather than the Sb 4 -containing systems theoretically studied so far, , namely, Zintl anions based on Sb 3 , with particular emphasis on the analysis of A 3 Sb 3 units. Species of the form A 2 Sb 2 can be understood as O 2 -analogous Zintl systems .…”

“…In the present work, we aim at an understanding of both structural and bonding features of a different class of Sb-based clusters rather than the Sb 4 -containing systems theoretically studied so far, 4,8 geometries of A 3 Sb 3 are closely related to those found in the O 3 molecule. Comparing units with different alkali constituents (A ) Na, K, Rb), we will show that the similarity between A 3 Sb 3 and ozone becomes more pronounced with increasing electron transfer from the alkali to the antimony atoms.…”