Density Functional Study of Tricyclo[3,3,1,1~(3,7)]decane and Tricyclo[3,3,1,1~(3,7)]decsilane and Their Halogen Derivatives

摘要

The BLYP/3-21G~* ab initio molecular orbital method from the Gaussian 94 computer program package was applied to study tricyclo[3,3,1,1~(3,7)]decane and tricyclo[3,3,1,1~(3,7)]decsilane molecules and their halogen derivatives (1,3,5,7-tetrahalotricyclo[3,3,1,1~(3,7)]decane and 1,3,5,7-tetrahalotricyclo[3,3,1,1~(3,7)]decsilane, C_(10)H_(12)X_4, and Si_(10)H_(12)X_4). The optimized structures of these compounds were obtained. Ionization potentials, HOMO and LUMO energies, energy gaps, heats of formation, atomization energies, and vibration frequencies were calculated. These calculations indicate that these molecules are stable and have T_d symmetry. tricyclo[3,3,1,1~(3,7)]decsilane and its halogen derivatives (Si_(10)H_(12)X_4) are found to have higher conductivity than that of tricyclo[3,3,1,1~(3,7)]decane and its halogen derivatives (C_(10)H_(12)X_4). 1,3,5,7-Tetraflourotricyclo[3,3,1,1~(3,7)]decane (C_(10)H_(12)F_4) and 1,3,5,7-tetraflourotricyclo[3,3,1,1~(3.7)]decsilane(Si_(10)H_(12)F_4) were found to be the easiest compounds to form and the most difficult to dissociate of all 1,3,5,7-tetrahalotricyclo[3,3,1,1~(3.7)]decane and 1,3,5,7-tetrahalotricyclo[3,3,1,1~(3.7)]decsilane compounds, respectively.