Gallium-dimethylamine and -trimethylamine were produced in pulsed laser vaporization molecular beams and studied by threshold photoionization and pulsed-field ionization zero electron kinetic energy (ZEKE) photoelectron spectroscopies and density functional theory calculations. Analyses of the ZEKE spectra yield molecular adiabatic ionization potentials and metal-ligand and ligand-based vibrational frequencies. Comparisons of the experimental and theoretical results establish the ground electronic states of the neutral and ionic complexes. The ionization potentials, Ga+/Ga-N stretching, and Ga+/Ga-N-C bending frequencies are 38 790, 206/177, and 132/128 cm(-1) for the dimethylamine complex and 38 081 cm-1, 188/133, and 111/92 cm(-1) for the trimethylamine species. The electronic ground states are (1)A(')/(2)A(') for Ga+/Ga-NH(CH3)(2) and (1)A(1)/(2)A(') for Ga+/Ga-N(CH3)(3). The calculated metal-ligand binding energies of Ga+/Ga-NH(CH2)(2) and -N(CH3)(3) are 36.2/9.7 and 37.1/8.5 kcal mol(-1), respectively. (C) 2003 American Institute of Physics.