Simultaneous Analysis of the Rovibrational Levels υ4=1, 2, and 3 of HCCI and DCCI Based on Infrared Spectra

Abstract The energy levels υ 4 =1, υ 4 =2, and υ 4 =3 of DCCI have been analyzed by using the fundamental ν 4 1 (470–520 cm −1 ) and the overtone 2ν 4 0 (955–1005 cm −1 ) bands together with the hot bands 2ν 4 0,2 ←ν 4 1 , 3ν 4 1,3 ←2ν 4 0,2 , and 3ν 4 1 ←ν 4 1 . In the case of HCCI the previously studied hot bands connected to ν 4 have been completed by adding 3ν 4 1 ←ν 4 1 into the analysis. The various l -type resonances have been taken into account in the analyses of both the isotopomers. Furthermore, the Coriolis resonance between the close-lying ν 3 and ν 4 of DCCI has been considered. Altogether, accurate values for the molecular constants and the resonance parameters have been obtained from simultaneous analysis and they have been compared with those from separate analyses for different levels.