On the displacements of centers of vibration-rotation bands under isotope substitution in polyatomic molecules

The 3ν2 Band of D216O

“…The vibrational energy E v ϭ 3474.3195 0 Ϯ 0.00030 cm Ϫ1 resulted from fitting is close to the estimated value 3472 cm Ϫ1 calculated from 3 2 band origin of H 2 16 O using the isotopic shift formulas (27). A comparison of the fitted parameters with those calculated using isotopic rules shows the agreement to be within 2% for the rotational constants and within 28% for the centrifugal distortion constants ⌬ k , ⌬ Jk , ⌬ J , ␦ k , ␦ J .…”

High-resolution study of the ν1+ν2 and ν2+ν3 strongly interacting bands of D2Se

“…As was shown in [26], physically meaningful rotational, centrifugal distortion, and resonance interaction parameters of isotopic species with different heavy atoms (Se atom in our case) should be linearly dependent on the mass of those atoms. For this reason, experimental energy values were fitted in a special way.…”

“…Moreover, the relative changes of the Se mass M are not larger than 5%. According to the general discussion given in [26], in the first approximation all spectroscopic parameters, except the vibrational wavenumbers, of the D 2 M Se species should be equal to those of D 2 80 Se. In turn, the vibrational isotopic shifts D(m k + m l ) of the band center (m k + m l ), upon isotopic substitution, can be estimated from the formula [26] …”

Rotational Analysis of the Ground State and the Lowest Fundamentals ν3, ν5, and ν6 of 13CH3D

“…The shifts of the band centers in the 13 C substitution can be estimated from the formula given in Ref. (8). Here M and MЈ are the masses of 12 C and 13 C nuclei, respectively.…”