High-Temperature Infrared Measurements in the Region of the Bending Fundamental of H12C14N, H12C15N, and H13C14N

Abstract

High-resolution measurements have been made on the infrared emission spectrum of H12C14N, H12C15N, and H13C14N at temperatures on the order of 1370 K. The measurements cover the region 400–850 cm−1 with a resolution of 0.006 cm−1. New room-temperature absorption measurements are also reported for H13C14N in the regions, 1200–1500 cm−1 and 2500–3700 cm−1. These measurements are combined with earlier measurements to obtain improved values for the rovibrational constants for these three isotopomers. The high temperatures allowed us to measure the bending vibrational levels up to the 0 1111 0 state, at more than 7900 cm−1 above the ground vibrational level, for H12C15N and H13C14N, and the 0 1010 0 state for H12C14N. The Coriolis interaction responsible for the laser transitions of H12C14N and H12C15N has also been observed, for the first time, for H13C14N. New re values are given using the Be values found in this paper and in a recent paper on deuterated isotopomers.