High-temperature infrared measurements in the region of the bending fundamental of (HCN)-C-12-N-14, (HCN)-C-12-N-15, and (HCN)-C-13-N-14

High-resolution measurements have been made on the infrared emission spectr um of (HCN)-C-12-N-14, (HCN)-C-12-N-15, and (HCN)-C-13-N-14 at temperatures on the order of 1370 K. The measurements cover the region 400-850 cm(-1) w ith a resolution of 0.006 cm(-1). New room-temperature absorption measureme nts are also reported for (HCN)-C-13-N-14 in the regions, 1200-1500 cm(-1) and 2500-3700 cm(-1) These measurements are combined with earlier measureme nts to obtain improved values for the rovibrational constants for these thr ee isotopomers. The high temperatures allowed us to measure the bending vib rational levels up to the 0 11(11) 0 state, at more than 7900 cm(-1) above the ground vibrational level, for (HCN)-C-12-N-15 and (HCN)-C-13-N-14, and the 0 10(10) 0 state for (HCN)-C-12-N-14. The Coriolis interaction responsi ble for the laser transitions of (HCN)-C-12-N-14 and (HCN)-C-12-N-15 has al so been observed, for the first time, for (HCN)-C-13-N-14. New r(e) values are given using the B-e values found in this paper and in a recent paper on deuterated isotopomers. (C) 2000 Academic Press.