NEW OBSERVATIONS AND ANALYSIS OF THE INFRARED VIBRATION-ROTATION SPECTRUM OF H-3(+)

The coverage of the infrared spectrum of the H-3(+) molecular ion is extended by further mesurements of the emission from a small high-pressure hollow-cathode electrical discharge cell, using the pressure-dependence of the intensities to distinguish the lines of H-3(+) from the many lies due to electronic transitions of H-2 in the same region. The lines were assigned by means of calculations with a large vibration-rotation basis, using a Morse-based discrete variable representation for the vibrations. Eight coefficients in the Meyer-Botschwina-Burton ab initio potential were adjusted in order to fit 621 lines of H-3(+) from this and previous work with a standard deviation of 0.118 cm(-1).