A density functional study of borane and alane monoammoniate (BH3NH3,AlH3NH3).

Molecular structures, harmonic vibrational frequencies, dissociation energies, and barriers to internal rotation have been determined using a Gaussian density functional method. Both local and nonlocal levels of theory have been employed. The calculated equilibrium geometry and harmonic vibrational frequencies for BH3NH3 compare well with those determined by microwave and infrared experiments. The rotational barrier is found to be 2.09 kcal/mol in very good agreement with the experimental data. The calculated properties for ammonia-alane (AlH3NH3) are compared with those obtained previously from high level correlated methods. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]