Synthesis and Properties of Uranium Sulfide Cations. An Evaluation of the Stability of Thiouranyl, {SUS}²⁺

Abstract

Atomic uranium cations, U⁺ and U²⁺, reacted with the facile sulfur-atom donor OCS to produce several monopositive and dipositive uranium sulfide species containing up to four sulfur atoms. Sequential abstraction of two sulfur atoms by U²⁺ resulted in US₂²⁺; density functional theory computations indicate that the ground-state structure for this species is side-on η²-S₂ triangular US₂²⁺, with the linear thiouranyl isomer, {SU^VIS}²⁺, some 171 kJ mol^–1 higher in energy. The result that the linear thiouranyl structure is a local minimum at a moderate energy suggests that it should be feasible to stabilize this moiety in molecular compounds