|NORMAL-MODES ANALYSIS OF (A)OVER-TILDE-STATE ACETYLENE BASED ON DIRECTLY OBSERVED FUNDAMENTAL VIBRATIONS
|Year of Publication
|Tobiason JD, Utz AL, Sibert EL, Crim FF
|Journal of Chemical Physics
|Recent experimental results permit a detailed normal modes analysis A-state acetylene (C2H2) and its isotopomers (C2HD and C2D2). Using only experimentally determined frequencies and measured or estimated anharmonicities, we determine harmonic frequencies for the 11 directly observed and unambiguously assigned vibrational fundamentals. The normal modes calculation varies force constants to fit the 11 harmonic frequencies and yields a complete set of harmonic frequencies, force constants, and Coriolis coefficients for the three isotopomers. A complete set of fundamental frequencies calculated from the set of harmonic frequencies allows a comparison to and, in some cases, suggests a reassessment of frequencies for tentatively assigned fundamental vibrations.
|J. Chem. Phys.