Department of Chemistry, University of Mauritius, Reduit, Mauritius.
J Phys Chem A. 2010 Apr 1;114(12):4210-23. doi: 10.1021/jp1006389.
A systematic theoretical investigation was carried out to study the reactions of various germylenes with germane. Molecular structures of the reactants (GeX(2) and GeHX, where X = H, F, Cl and Br) plus GeH(4), transition states, and products have been optimized to understand the effects of halo-substituted germylenes. The basis set used is of double-zeta plus polarization quality with additional s- and p-type diffuse functions. Consistent with experiment, the theoretical gas-phase reaction GeH(2) + GeH(4) --> Ge(2)H(6) possesses a negative activation energy. The predicted activation energies reveal interesting trends for both mono- and di- halo-substituted germylenes, -1.5 [GeH(2)], +20.5 [GeHF], +59.9 [GeF(2)], +18.0 [GeHCl], +46.8 [GeCl(2)], +17.3 [GeHBr], and +42.9 kcal mol(-1) [GeBr(2)]. There is a noteworthy relationship between the activation energies and the singlet-triplet splittings of the divalent germylenes. We report for the first time rate constants for the transfer of hydrogen, evaluated using standard transition-state theory with tunneling corrections. These results are analyzed and compared to the available experimental and previous theoretical findings for the gas-phase reactions involving germylene derivatives and germanium analogues.
进行了系统的理论研究，以研究各种锗烯与锗烷的反应。反应物（GeX(2)和 GeHX，其中 X = H、F、Cl 和 Br）加上 GeH(4)的分子结构、过渡态和产物都经过了优化，以了解卤代锗烯的影响。使用的基组是双-zeta 加极化质量，外加 s 和 p 型弥散函数。与实验一致，理论气相反应 GeH(2) + GeH(4) --> Ge(2)H(6)具有负的活化能。对于单卤代和二卤代锗烯，预测的活化能揭示了有趣的趋势，分别为-1.5 [GeH(2)]、+20.5 [GeHF]、+59.9 [GeF(2)]、+18.0 [GeHCl]、+46.8 [GeCl(2)]、+17.3 [GeHBr]和+42.9 kcal mol(-1) [GeBr(2)]。二价锗烯的活化能与单重态-三重态分裂之间存在显著关系。我们首次报道了使用标准过渡态理论和隧道校正评估的氢转移速率常数。这些结果经过分析，并与气相反应中涉及锗烯衍生物和锗类似物的现有实验和先前理论结果进行了比较。
