An ab initio and density functional theory study of the dimethylzinc hydrogen selenide adduct:: (CH3)2Zn:SeH2

The molecular structure (equilibrium geometry) and binding energy of the dimethylzinc (DMZn)-hydrogen selenide (H2Se) adduct, (CH3)(2)Zn:SeH2, have been computed with ab initio molecular orbital and density functional theory (DFT) methods and, where possible, compared with experimental results. The structure of the precursors DMZn and H2Se are perturbed to only a small extent upon adduct formation. (CH3)(2)Zn:SeH2 was found to be similar to 3 kcal mol(-1) less stable than the precursors at the B3LYP/6-311 + G(2d,p)//B3LYP/6-311 + G(2d,p) level of computation, indicating that the (CH3)(2)Zn:SeH2 adduct is unlikely to be a stable gas-phase species under chemical vapour deposition conditions. Further calculations at the B3LYP/6-311 + G(2d,p)//B3LYP/6-311 + G(2d,p) level of computation suggest that the 1:2 adduct species, (CH3)(2)Zn:(SeH2)(2), is much less stable than the 1:1 adduct and consequently the precursors by similar to 19 kcal mol(-1). (C) 1998 Elsevier Science B.V. All rights reserved.