Intensities of Electronic Transitions in Ammonia

Abstract

Absolute intensity measurements of the transitions in ammonia vapor with maxima at 52,500, 66,000, and 77,000 cm⁻¹ are reported. Calculations are made of the intensities of the first and third transitions, using non‐bonding nitrogen orbitals, of the form suggested by Slater. The calculated values are considerably lower than the measured values, but may be improved by variation of the effective nuclear charge. Similar calculations for the second transition are less conclusive, but seem to indicate that it also may originate from a nearly non‐bonding nitrogen orbital. Some other possible origins of this transition are considered and rejected on the basis of either their energy or their intensity.