Home – Home – Jornals – Journal of Structural Chemistry 2014 number 1

Quantum chemical B3LYP/cc-pVTZ, PBE0/cc-pVTZ, and MP2(full)/6-311G(d,p) methods are used to calculate the structural parameters of dodecasilsequioxane H₁₂Si₁₂O₁₈ and the H₁₂Si₁₂O₁₈⁺ cation. According to DFT/cc-pVTZ calculations the energy of H₁₂Si₁₂O₁₈(D_6h) is 1.3-1.7 kcal/mol higher than the energy of H₁₂Si₁₂O₁₈(D_2d). A reduction of the basis set results in a greater energy difference of H₁₂Si₁₂O₁₈ isomers. For the cation ²B_2u and ²B₁ electronic states are obtained, which correspond to symmetric equilibrium structures H₁₂Si₁₂O₁₈⁺ (D_6h) and (D₂) respectively. For the He@H₁₂Si₁₂O₁₈ endocomplex the D_2d symmetry is obtained; for He₂@H₁₂Si₁₂O₁₈ the D_2h symmetry; and for H₂@H₁₂Si₁₂O₁₈ the D_6h symmetry.