RESUMO
Electronic structure calculations for late transition metals coordinated by two dithiolene ligands are found to be consistent with existing structures and also predict the geometries of Ni(I) species for which no solid state structures have been reported. Of particular interest are the compounds [M(mnt)2 ]n- (M = Ni, Pd, and Pt with n = 1, 2, 3; M = Cu with n = 2). Calculations have been performed with and without ion-paring with M(diglyme)+ (M = Li, Na, K) and R4 N+ (R = Me, Bu). The diagonal twist angle between two NiS2 planes is found to depend on (i) the metal's d-electron count, spanning from 0° (planar d7 and d8 ), to 42° (d9 ), to 90° (pseudo-tetrahedral d10 ), and (ii) the identity of the ion-paired cations. Calculated ion-pairing energies are functions of the cation size and charge-density, being larger for alkali-metal coordinated diglyme and smaller for tetra-alkyl ammonium cations. © 2016 Wiley Periodicals, Inc.
