DIODE-LASER SPECTRA AND POTENTIAL-ENERGY CURVE FOR THE MOLECULAR ION HEH+

Rovibrational levels of HeH+ have been calculated by numerical integration of the Schrödinger equation with a potential taken from the literature. After corrections were applied to the potential by using experimental data of the v = 1 ← 0 and v = 2 ← 1 bands of HeH+, rovibrational levels with 0 ≤ J ≤ 15 and 0 ≤ v ≤ 4 for HeH+ and HeD+ were predicted. The v = 3 ← 2 band of HeH+ and the v = 2 ← 1, v = 3 ← 2, and v = 4 ← 3 bands of HeD+ have been observed with a tunable diode laser system. The mean difference between experimental measurements and theoretical predictions is less than 0.1 cm-1. Molecular constants for both isotopic species were determined by a fit to all available data. © 1992.