ADIABATIC POTENTIAL-ENERGY SURFACES OF THE H-2(-FIELD() ION IN A STRONG MAGNETIC)

We use a recently established and optimized atomic orbital basis set t o perform extensive numerical calculations on the hydrogen molecular i on in a strong magnetic field. Many excited electronic states with ger ade and ungerade parity as well as their potential-energy curves are i nvestigated for the perpendicular configuration, i.e., for orthogonal internuclear and magnetic-field axes. The main issues of our investiga tion are the local as well as global topological properties of the pot ential-energy surfaces of the six energetically lowest electronic stat es of the H-2(+) ion in a strong magnetic field B=1.0 a.u. Our results show the existence of a variety of different possibilities for the to pological behavior of the potential-energy surfaces: for the lowest el ectronic states the global equilibrium configuration is either the par allel or the perpendicular configuration, which are both distinguished by their higher symmetry. As a major result we observe, for the 3(u) electronic state, the effect of a global symmetry lowering: the global equilibrium configuration of the 3, potential-energy surface is at th eta=27 degrees, i.e., a configuration that strongly deviates from the distinct parallel or orthogonal configurations. Examinations of the el ectronic probability density distributions with varying angle theta re veal the origin of the topological behavior of the different surfaces.