Comparative ab initio study of the structures and stabilities of the ethane dication C2H6(2+) and its silicon analogues Si2H6(2+) and CSiH6(2+)

Golam Rasul; G K Surya Prakash; George A Olah

doi:10.1021/jp0404652

Comparative ab initio study of the structures and stabilities of the ethane dication C2H6(2+) and its silicon analogues Si2H6(2+) and CSiH6(2+)

J Phys Chem A. 2005 Feb 10;109(5):798-801. doi: 10.1021/jp0404652.

Authors

Golam Rasul¹, G K Surya Prakash, George A Olah

Affiliation

¹ Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, University Park, Los Angeles, California 90089-1661, USA. rasul@usc.edu

PMID: 16838949
DOI: 10.1021/jp0404652

Abstract

Ab initio MP2/6-311G and QCISD(T)/6-311G levels as well as Gaussian-2 theory were used to perform a comparative study of the structures and stabilities of the ethane dication C(2)H(6)(2+) and its silicon analogues Si(2)H(6)(2+) and CSiH(6)(2+). Similar to previous HF/6-31G results, our present calculations also indicate that the two-electron three-center (2e-3c) bonded carbonium-carbenium structure 1 is more stable than the doubly hydrogen bridged diborane-type structure 2 by about 12 kcal/mol. For the silicon analogue Si(2)H(6)(2+) the calculations, however, indicate that the 2e-3c bonded siliconium-silicenium structure 8 is about 9 kcal/mol less stable than doubly hydrogen bridged structure 9. Similar results were also computed for carbon-silicon mixed CSiH(6)(2+) dication structures. These studies are in agreement with the more electropositive character of silicon compared to carbon. Possible dissociation paths of the minimum structures were also calculated.