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The v 7 + vs A-type band of C~H4 has been recorded between 1932 and 1847 cm -1 with a resolution of 0"06 cm -x. The transitions with K_l~<8 and J ~< 25 have been assigned. Although slight Coriolis resonances perturb the band, the analysis has been made easy through the use of an elaborate set of asymmetric top computer programmes. The band centre and a set of upper state constants have been obtained. With these constants, 288 observed upper state energy levels have been fitted with a standard deviation of 0-021 cm -1.Using very simple expressions, we have predicted all the resonance effects perturbing the levels of ethylene near 2000 cm -1. This led us to the identification of the v4 + vs and vs + vt0 combination bands in low resolution spectra.

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