Protonic Structure of Molecules. I. Ammonia Molecules

The ammonia molecule is treated in this calculation with the nitrogen fixed and with the electrons and protons described by Slater orbitals. The Hamiltonian includes the kinetic-energy operators of the protons. One minimal basis configuration was used for the electrons, and twenty configurations involving six orthogonal spin orbitals constructed from the $s$, $p_x$, $p_y$, and $p_z$ basis orbitals were used for the protons. Proton delocalization was found to be significant, and the kinetic energies of the protons were found to be about 3 kcal/mole. The calculation yielded a protonic spectrum similar to the electronic spectrum. A ground-state energy of -55.44 hartrees was obtained.