High-resolution Fourier transform spectra of CH2D2: The 2ν5(A1), ν3 + ν9(B2), ν5 + ν9(B1), and ν3 + ν7(B1) vibrational bands

High-Resolution Near Infrared Spectroscopy and Vibrational Dynamics of Dideuteromethane (CH2D2)

“…The small experimental uncertainty (estimated to be between 0.0001 and 0.001 cm −1 for different bands and different spectral regions and always below 0.01 cm −1 ) of the numerous band centers allowed us to correctly determine the values of the harmonic wavenumbers ω k , anharmonic coefficients x k j , and of some resonance interaction parameters. A total of 74 band centers derived in the present contribution (71 new and 3 redetermined for the bands 2ν 3 , ν 1 , and ν 6 ) were added to the 19 band centers known previously from refs , , , , and and fitted with the simple model of a vibrational Hamiltonian matrix which takes into account some relevant resonance interactions H v . = ∑ v , v ̃ | v ⟩ ⟨ ṽ | h v ṽ Here the summation includes all vibrational states studied. The diagonal elements of the matrix have the form h v v = ∑ k ω k true( v k + 1 2 true) + ∑ k , m ≥ k x k m true( v k + 1 2 true) true( v m + 1 2 true) + ∑ k , m ≥ k , n ≥ m y k m n …”

“…Table summarizes the nine vibrational fundamentals as known today. A total of 22 vibrational bands had been studied at moderate to high resolution prior to the present work, where we reanalyze also three of the previously known bands. − The far-infrared pure rotational spectrum has also been studied with the main goal of deriving the permanent dipole moment of CH 2 D 2 including the answer to the long standing question of its sign. , …”

“…A total of 22 vibrational bands had been studied at moderate to high resolution prior to the present work, where we reanalyze also three of the previously known bands. [48][49][50][51][52][53][54][55][56][57][58][59][60] The farinfrared pure rotational spectrum has also been studied with the main goal of deriving the permanent dipole moment of CH 2 D 2 including the answer to the long standing question of its sign. 61,62 In our two previous papers, we have complemented the lowenergy spectra by observing and analyzing previously undetected, weak, or forbidden transitions for example to levels of A 2 symmetry or weaker overtone and combinations levels.…”

High resolution Fourier transform spectroscopy of CH2D2in the region 2350–2650 cm−1: the bands ν5+ ν7, 2ν9, ν3+ ν4, ν3+ ν7and ν5+ ν9

“…High resolution studies of the first overtone and combination bands have been reported in refs. [33][34][35][36] where the bands 5 , n 5 þ n 9 and 2n 3 were analyzed. It should be mentioned, however, that ro-vibrational transitions with J up to J max ¼ 9 were assigned for the bands included in refs.…”