The absorption of ethylene in the 10- mu m region

The nu /sub 7/, nu /sub 10/, and nu /sub 4/ interacting band system has been studied from three complementary sources: classical, diode laser, and waveguide laser spectra. In addition to the two first-order Coriolis interaction terms associated with zeta /sub 7,10//sup a/ and zeta /sub 4,10//sup b /, we were obliged to introduce the corresponding second-order terms to obtain a statistical agreement between calculated and experimental data. High-quality vibrational and rotational data are presented for the two infrared active fundamentals, nu /sub 7/ and nu /sub 10/, and the rotational constants for the inactive nu /sub 4/ fundamental are determined for the first time. The authors present the list of all the infrared transitions starting from the vibrational ground state of ethylene and being in quasi coincidence with CO/sub 2/ or N/sub 2/O laser lines.