Chemistry Department, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, United Kingdom.
J Chem Phys. 2013 Aug 14;139(6):064308. doi: 10.1063/1.4817533.
Full-dimensional variational calculations are reported for the isomerising disilyne molecule, Si2H2. Large-scale calculations using coordinates based on orthogonal satellite vectors permitted the computation of excited vibrational state energies and wavefunctions for all four isomeric forms: dibridged Si(H2)Si, monobridged Si(H)SiH, disilavinylidene H2SiSi, and trans-bent HSiSiH. Energies and wavefunctions have been determined for the lowest 2400 totally symmetric vibrational states; this set includes highly excited states above all three chemically relevant isomerisation barriers--up to about 8300 cm(-1) above the (dibridged) ground state. States strongly localised in the dibridged, monobridged, and disilavinylidene regions of the potential energy surface have been found as well as many partially or fully delocalised states. For the trans-bent form, only partially localised states have been identified. Comparisons are made with similar literature calculations on the isovalent acetylene-vinylidene system HCCH/H2CC.
全维变分计算报道了异构化二硅烯分子 Si2H2 的情况。使用基于正交卫星向量的坐标进行的大规模计算允许计算所有四种异构形式的激发振动态能量和波函数：双桥接 Si(H2)Si、单桥接 Si(H)SiH、二硅烯叉 H2SiSi 和反式弯曲 HSiSiH。已经确定了最低 2400 个全对称振动态的能量和波函数；这组包括在所有三个化学相关异构化势垒之上的高度激发态 - 高达约 8300 cm(-1) 高于（双桥接）基态。在势能表面的双桥接、单桥接和二硅烯叉区域中发现了强局域态以及许多部分或完全离域态。对于反式弯曲形式，仅识别出部分局域态。与 HCCH/H2CC 等电子乙炔-乙烯基系统的类似文献计算进行了比较。
