Electron deficiency in tetrahedral transition-metal clusters: electronic structure and magnetic properties of [Ru4(C6H6)4(H)4]2+
Résumé
Analysis of the electronic structure of the electron-deficient cluster cation [Ru4(C6H6)4H4]2+ (12+) by density functional theory calculations shows a very small energy gap (0.06 eV) between the diamagnetic singlet state and the paramagnetic triplet state, as a consequence of the absence of a significant Jahn-Teller distortion in the molecular structure of 12+. Magnetic measurements of [1]Cl2, [1][BF4]2, and [1][PF6]2 show 12+ to be diamagnetic in the fundamental state, with some weak temperature-independent paramagnetism, depending upon the nature of the counterion.