Structure and bonding in the trichalcogenometaphosphate-pyridine anions [PX3-Py]- (X = O, S, Se, Te)

Gökçinar E., Karaghiosoff K., Klapötke T. M., Evangelisti C., Rotter C.

Phosphorus, Sulfur and Silicon and the Related Elements, vol.185, no.12, pp.2527-2534, 2010 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 185 Issue: 12
  • Publication Date: 2010
  • Doi Number: 10.1080/10426501003724913
  • Journal Name: Phosphorus, Sulfur and Silicon and the Related Elements
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2527-2534
  • Keywords: Acidity/basicity, Calculations, NMR shifts, Trichalcogenometaphosphate anions, VB structures
  • Ankara University Affiliated: No

Abstract

The structures, bonding, NMR chemical shifts, and Lewis acid/base behavior of the trichalcogenometaphosphate-pyridine anions [PX3 - Py]- (X = O, S, Se, Te) have been evaluated theoretically on the basis of B3LYP/ECP(Se,Te) + cc-pVTZ//PM3 calculations using quasirelativistic pseudopotentials for Se and Te. The molecular and electronic structures of the trichalcogenometaphosphate- pyridine adducts [PX3 - Py]- (X = O, S, Se, Te) were calculated, and the bonding was analyzed and discussed on the basis of natural bond orbital (NBO) analyses and qualitative valence bond (VB) considerations. The (θ (px)-LP(N)) → (θ(px)-LP*(P)) donor-acceptor interaction increases, and, consequently, the P-N bond length decreases from PO3 - Py- (weak interaction, long P-N bond) to PTe3 - Py- (strong interaction, short P-N bond). This theoretical finding is in good accord with the measured P-N bond lengths in [PSe3 - Py]- and [PTe3 - Py]-. In the gas phase, all four [PX3 - Py]- (X = O, S, Se, Te) adducts are unstable with respect to dissociation into free PX3- and pyridine. © Taylor & Francis Group, LLC.