Accurate ab initio based multisheeted double many-body expansion potential energy surface for the three lowest electronic singlet states of H_3~+

摘要

The authors present diabatic and adiabatic potential energy surfaces for the three lowest electronic singlet states of H_3~+.The modeling of the surfaces is based on the multi-sheeted double many-body expansion method which consists of dressing the various matrix elements of the diatomics-in-molecules potential matrix with three-body terms.The avoided crossing between the two lowest states and the conical intersection between the second and the third state are accurately represented by construction.