An ab initio and density functional theory study of the trimethylgallium-hydrogen selenide adduct: (CH 3) 3Ga:SeH 2

Abstract

The molecular structure (equilibrium geometry) and binding energy of the trimethylgallium (TMGa)-hydrogen selenide (H 2Se) adduct, (CH 3) 3Ga:SeH 2, have been computed using ab initio molecular orbital and density functional theory (DFT) methods, and where possible, compared with experimental results. The structure of the precursors TMGa and H 2Se are perturbed to only a small extent upon adduct formation. (CH 3) 3Ga:SeH 2 was found to be ≈ 16.6 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 (CH 3) 3Ga:SeH 2 adduct is unlikely to be a stable gas phase species under MOCVD growth conditions. However, the H 3Ga:SeH 2 adduct was found to be ≈ 6.5 kcal mol −1 more stable than the precursors at the B3LYP/6–311 + G(2d,p)//B3LYP/6–311 + G(2d,p) level indicating that H 3Ga:SeH 2 should be a stable GaSe bonded species.