On the Rovibrational Levels of the H3 ÷ and H2d ÷ Molecules

Variationally exact rovibrational levels for the H3 + and H2D ÷ molecules are calculated using a recently published accurate potential. Vibrational fundamentals are va1=3191 cm-1 and vE=2494 (2521.6) cm-1 for H3 + and vl=3000cm-1, v~=2184cm-x and v3=2310cm-1 for H~D +. For H3 + calculated ground state rotational constants are B0 = 43.51 (43-57) cm-1, Co = 20.59 (20-71) cm-1, Dj ° = 0.04 (0.05) cm-1, Djn° =-0.07 (-0.10) cm-1 and DK=0.04 (0-04)cm-1 (where experimental results are given in parenthesis). An attempt is made to stabilize many vibrational states. We thus reassess the results of Carney and Porter. The implications for astrophysics, the interpretation of the infrared spectrum of H3 + near its dissociation limit and the unassigned spectrum of H,D + are discussed.