S_4~(2-) Rings,Disulfides,and Sulfides in Transition-Metal Complexes:The Subtle Interplay of Oxidation and Structure

摘要

A sulfur atom,with its six valence electrons,may reach an octet by association into S_n rings.Two-electron reduction of the rings usually leads to polysulfide chains S_n~(2-).Small,neutral S_n rings are rare;witness S_4,for which there is scant evidence and continuing theoretical uncertainty about its structure As is the case for S3,the S4 ring's instability is presumably due to lone-pair repulsion.