Microwave, Submillimeter-Wave, and High-Resolution FTIR Spectra of AsF3in the ν2and ν4States

Analysis of Rotational and Rovibrational Spectra of SiDF3 in the Ground and v4 = 1 Excited States

“…Relation [10] is not fulfilled with the values of the constants given above. This is a further argument for regarding them only as effective parameters.…”

The vt=1 Rovibrational Hamiltonian for C3v Symmetric Top Molecules Containing One Quadrupolar Nucleus: Reductions and Application to AsF3

“…Higher order constraints on the parameters f K 22 or τ J K have been applied in the same way as in Ref. (1). The data could be fitted close to their experimental accuracy.…”

“…In 1996 we reported the observation of direct l-type resonance transitions in the v 4 = 1 vibrational state of AsF 3 , measured in Kiel by means of microwave Fourier transform spectroscopy (1). The transitions showed splittings due to the arsenic nuclear quadrupole coupling but only the center frequencies of the transitions were reported and analyzed, together with data obtained in the millimeter and infrared ranges.…”

The Reduced Effective Vibration–Rotational Hamiltonian for the vt = 2 Levels of C3v Symmetric-Top Molecules

“…Equations [5][6][7][8] apply equally well also to the first overtone v t ϭ 2 and on this basis one would expect that the same collinearity problems would be encountered. The preliminary analysis of the direct l-type resonance transitions in the v 10 ϭ 2 vibrational state of CF 3 CCH (14) demonstrated, however, rather surprisingly that all four spectroscopic constants J , K , q 12 , d t can be determined for this state simultaneously without correlation problems.…”

“…The effect of the transformation on the molecular parameters can be written as follows (3,10): xxxz ϭ xxxz ϩ 12͑ A Ϫ B͒t, [4] q 12 ϭ q 12 ϩ 1 2 Fs, [5] d t ϭ d t ϩ 2q 22 s Ϫ 6At, [6] K ϭ K Ϫ 8q 12 s Ϫ 2Fs 2 , [7] J ϭ J ϩ 8q 12 s ϩ 2Fs 2 , [8] where…”