High-Resolution Coherent Raman Spectra of Vibrationally Excited14N2and15N2

Autor: Orlov, M.L., Ogilvie, J.F., Nibler, J.W.
Zdroj: Journal of Molecular Spectroscopy; September 1997, Vol. 185 Issue: 1 p128-141, 14p
Abstrakt: At an effective resolution of 0.001 cm−1, we measured coherent anti-Stokes Raman spectra of electrically discharged14N2and15N2in the electronic ground stateX1Σg+, specificallyQbranches of bands with Δv= 1 up tov′ = 8 for14N2andv′ = 7 for15N2, andOandSbranches of the fundamental band of15N2. Account is taken of small wavenumber shifts due to pressure, AC Stark, and |χ|2interference effects. Separate fits of theQ-branch data of each isotopic variant, combined with selected data from the literature, yield term coefficientsYklandUklor potential-energy coefficientscjthat reproduce wavenumbers of measured spectral lines generally within 0.004 cm−1. The value of the harmonic vibrational parameter ωeis 2358.5402(4) cm−1for14N2and 2278.7913(7) cm−1for15N2. Efforts to combine spectral data of both isotopic variants to distinguish adiabatic and nonadiabatic effects arising from incomplete separation of electronic and nuclear motion in N2were unsuccessful.
Databáze: Supplemental Index