The structures of Sn(SBut)4 and Sn(SCy)4 have been determined and adopt S4 and D2 conformations respectively; the anion [(PhS)Sn3]−, as its Ph4P+ salt, has a structure approaching Cs symmetry. In all three compounds, there are large variations in the ∠S–Sn–S within the same molecule, which have been rationalised in terms of the C–S–Sn–S–C conformations. For Sn(SR)4, the ∠S–Sn–S increases as the conformations change from trans, trans to trans, gauche and gauche, gauche, as the number of eclipsed lone pairs decreases and this rationale is shown to be applicable to a variety of A(ER)4 (A = C, Si, Ge, Sn; E = O, S, Se) and related [Mo(SR)4, Ga(SR)4−] systems.
AM1 calculations have been used to model the ∠S–Sn–S magnitudes and also provide insights into the decomposition mechanisms of these and related species which are relevant to chemical vapour deposition processes.
Sn(
SBut)4 和 Sn(SCy)4 的结构已被确定,并分别采用 S4 和 D2 构象;阴离子 [(PhS)Sn3]−,作为其 Ph4P+ 盐,具有接近 Cs 对称性的结构。在这三种化合物中,同一分子内的 ∠S–Sn–S 存在较大的变化,这可以通过 C–S–Sn–S–C 构象来解释。对于 Sn(SR)4,当构象从反式、反式转变为反式、顺式和顺式、顺式时,∠S–Sn–S 会随着重叠孤对数量的减少而增加,这一解释也适用于多种 A(ER)4(A = C, Si, Ge, Sn;E = O, S, Se)及相关的 [Mo(SR)4, Ga(SR)4−] 系统。
AM1 计算被用来模拟 ∠S–Sn–S 的大小,并提供了对这些及相关物种分解机制的见解,这与
化学气相沉积过程相关。