Global, ab initio potential energy surfaces for HCP in its ground 1 (1)Sigma(+) (1 (1)A＇) and low-lying excited 1 (1)A ", 2 (1)A＇, and 1 (1)Delta(2 (1)A ") electronic states are determined. The multireference configuration interaction method at the double zeta with polarization basis set level is used, although some calculations augmented with diffuse functions are also discussed. Numerous quantum mechanical rovibrational states are then obtained for these surfaces, with emphasis on those corresponding to excited electronic state levels which have not been studied theoretically before. The results agree reasonably well with available experimental data for the 1 (1)A " state. Furthermore, the presence of certain local minima on the 1 (1)A " and 2 (1)A＇ surfaces leads to one new series of levels on the 1 (1)A " surface, and two new series on the 2 (1)A＇ surface. (C) 2000 American Institute of Physics. [S0021-9606(00)30413-5].