Quantum chemical calculations of the gas-phase reactions of tertiarybutylhydrazine ((CH3)(3)CNHNH2) were performed to understand the possible reaction path when used as a nitrogen source for gallium nitride film growth. Thermochemical prediction using density functional theory showed that the reaction to form hydrazine (N2H4) and isobutene ((CH3)(2)CCH2) through P-hydride elimination in the tertiarybutyl ligand has the lowest activation energy barrier of 63 kcal/mol. In addition, rate constants calculations using transition-state theory also showed that the beta-hydride elimination reaction predominated over all other gas-phase reaction paths. The calculated thermochemical and kinetic results agreed very well with the reported pyrolysis data. (c) 2005 Elsevier B.V. All rights reserved.