Calculated rotational and rovibrational transitions in the spectrum of H3(+)

Abstract

New calculations of line strengths and transition frequencies for the forbidden rotational spectrum and the nu2 fundamental rovibrational band of H3(+) are presented. These first principles calculations use the highly accurate ab initio electronic potential energy surface of Meyer, Botschwina, and Burton (1986), which has previously been shown by the authors to give rovibrational transition frequencies, rotational constants and vibrational fundamentals of spectroscopic accuracy. The line strengths calculated for the pure rotational spectrum in the vibrational ground state are in general agreement with those previously predicted by Pan and Oka (1986), although individual line strengths may differ by as much as 50 percent. The data are presented to assist with the interstellar detection of this astrophysically important molecular ion. 25 references.