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Isobutane Infrared Bands: Partial Rotational Assignments, ab Initio Calculations, and Local Mode Analysis
Peter F Bernath1, Dror M Bittner1, Edwin L Sibert Iii2
1Department of Chemistry and Biochemistry , Old Dominion University , Norfolk , Virginia 23529 , United States.
Abstract:
High-resolution infrared spectra of the symmetric top isobutane CH(CH3)3 were assigned with the help of ab initio calculations. The strong parallel band ν5(a1) with an origin at 1396.54741(76) cm-1 and the ν4(a1) mode, the CH2 scissors, at 1478.20363(41) cm-1 were rotationally analyzed. The bands in the C-H stretching region were assigned with the help of an anharmonic calculation and a local mode analysis.
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