Preparation, structure and analysis of the bonding in the molecular entity (OSO)2Li{[AlF(ORF)3]Li[Al(ORF)4]} (RF = C(CF3)3)

Dalton Trans. 2010 Mar 14;39(10):2587-96. doi: 10.1039/b923291e. Epub 2010 Jan 27.

Abstract

The (SO(2))(2)Li[AlF(OR(F))(3)]Li[Al(OR(F))(4)] (1) (R(F) = C(CF(3))(3)) molecular entity was obtained by thermal decomposition of Li[Al(OR(F))(4)] followed by crystallization from liquid SO(2). 1, containing two SO(2) molecules eta(1)-O coordinated to Li(+), was structurally characterized by single crystal X-ray diffraction and NMR spectroscopy in SO(2)(l). Bonding analyses of 1 (bond valency units, AIM analysis, atomic charges, bond orders) show that 1 can be either considered as a Li(OSO)(2)(+) complex stabilized by the large WCA [AlF(OR(F))(3)](-)Li(+)[Al(OR(F))(4)](-) or as consisting of 2 SO(2), 2 Li(+), [AlF(OR(F))(3)](-), and [Al(OR(F))(4)](-) joined by electrostatic interactions into the discrete molecular entity 1. The bonding between Li(+) and SO(2) molecules is shown to be almost completely attributable to monopole-induced dipole electrostatic interactions. Theoretical gas phase lithium ion affinity of SO(2) is determined to be stronger than its silver(I) ion affinity owing largely to the shorter lithium SO(2) contacts in the calculated structures that increase the electrostatic interaction.