Perturbations in rotational branching ratios of the I{sup 1} {Pi}{sup -}{sub g}, J{sup 1} {Delta}{sup -}{sub g} {yields} C{sup 1}{Pi}{sub u} transitions in an H{sub 2} molecule
- St. Petersburg Univ. (Russian Federation)
For the first time, the ratios of the spontaneous emission probabilities (rotational branching ratios) have been measured for pairs of spectral lines having a common upper electronic-vibrational-rotational level but belonging to different R, P, and Q branches of the diagonal (v{prime}= v{double_prime}= 0 - 2) bands of the I{sup 1}{Pi}{sub g}{sup -}, J {sup 1}{Delta}{sub g}{sup -}{r_arrow}C{sup 1}{Pi}{sub u} electronic transitions of the H{sub 2} molecule. Significant discrepancy was observed between the branching ratios measured and the values predicted by the adiabatic theory. Within the framework of the nonadiabatic model taking into account the electronic-rotational interaction of the 3d{pi}{sup 1}{Pi}{sub g}{sup -} and 3d{delta}{sup 1}{Delta}{sub g}{sup -} states, expansion coefficients states of the cients in the Born-Oppenheimer basis set for the perturbed wave functions of the I{sub 1}{Pi} and J{sub 1}{Delta}{sub g}{sup -} states of the H{sub 2} and D{sub 2} molecules are calculated from the data on the electronic-vibrational-rotational terms available in the literature. This allows us to obtain the ratio of the effective dipole moments of the 3d{delta}{sup 1}{Delta}{sub g}{r_arrow}2p{pi}{sup 1}{Pi}{sub u} and 3d{pi}{sup 1}{sup 1}{Pi}{sub g}{r_arrow}2p{pi}{sup 1}{Pi}{sub u} electronic transitions (-1.42 {+-} 0.02) from the experimental values of the rotational branching ratios. This value appears to be close to the value of -1.36 {+-}0.02 that we found earlier for similar transitions between triplet states and close to the value of -{radical}2 corresponding to the case of pure precession. On the basis of examining of the spectrum of the H{sub 2} molecule, rotational branching ratios are predicted for the diagonal bands of the I{sup 1}{Pi}{sub g}{sup -}, J{sup 1}{Delta}{sub g}{sup - }{r_arrow}C{sup 1}{Pi}{sub u} spontaneous transitions of the D{sub 2} molecule.
- OSTI ID:
- 223803
- Journal Information:
- Optics and Spectroscopy, Vol. 78, Issue 4; Other Information: PBD: Apr 1995; TN: Translated from Optika i Spektroskopiya; 78: No. 4, 628-641(1995)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Fine structure of 3s,3d: /sup 3/. sigma. , /sup 3/Pi, /sup 3/. delta. complex of H/sub 2/ by Doppler-free, laser spectroscopy
Doppler-free optogalvanic spectrum of He/sub 2/ b /sup 3/Pi/sub g/--f /sup 3/. delta. /sub u/ transition