TY - JOUR

T1 - Semiempirical determination of the ratio of the dipole moments for the 3d1Δg → 2p1Πu and 3d1Πg → 2p1Πu electronic transitions in the hydrogen molecule

AU - Astashkevich, S. A.

AU - Kokina, N. V.

AU - Lavrov, B. P.

PY - 1996/12/1

Y1 - 1996/12/1

N2 - The line strength ratios of lines having a common upper rovibronic level but belonging to different P, Q, and R branches (rotational branching ratios) are, for the first time, measured for the diagonal (v′ = v″ = 0-3) bands of the I1Πg- , J1Δg- → C1Πu± electronic transitions of the D2 molecule. Within the framework of the nonadiabatic model, the ratio of the dipole moments of the 3d1Δg → 2p1Πuand 3d1Πg → 2p1Πu electronic transitions. M2pπ3dΔ/M2pπ3dπ, was obtained from the previously calculated expansion coefficients in the Born- Oppenheimer basis set of perturbed wave functions of the I1Πg- and J1Δg- states of the D2 molecule and experimental values of rotational branching ratios. It was found that, as in the case of H2, there is a significant discrepancy between the values of M2pπ3dΔ/M2pπ3dπ derived from the analysis of experimental data on different electronic transitions: I1Πg- → C1Πu± and J1Δg- → C1Πu±. The reasons for this discrepancy are discussed. At the same time, when the data on both molecules are considered on an equal footing, the effective value of M2pπ3dΔ/M2pπ3dπ = -1.42 ± 0.01, which agrees well with the value of -1.35 ± 0.05 that we obtained earlier for transitions between similar triplet states of H2 and D2 and is close to the estimate of - √2 in the pure precession approximation, corresponds to the whole body of the measured rotational branching ratios of the molecules H2 and D2.

AB - The line strength ratios of lines having a common upper rovibronic level but belonging to different P, Q, and R branches (rotational branching ratios) are, for the first time, measured for the diagonal (v′ = v″ = 0-3) bands of the I1Πg- , J1Δg- → C1Πu± electronic transitions of the D2 molecule. Within the framework of the nonadiabatic model, the ratio of the dipole moments of the 3d1Δg → 2p1Πuand 3d1Πg → 2p1Πu electronic transitions. M2pπ3dΔ/M2pπ3dπ, was obtained from the previously calculated expansion coefficients in the Born- Oppenheimer basis set of perturbed wave functions of the I1Πg- and J1Δg- states of the D2 molecule and experimental values of rotational branching ratios. It was found that, as in the case of H2, there is a significant discrepancy between the values of M2pπ3dΔ/M2pπ3dπ derived from the analysis of experimental data on different electronic transitions: I1Πg- → C1Πu± and J1Δg- → C1Πu±. The reasons for this discrepancy are discussed. At the same time, when the data on both molecules are considered on an equal footing, the effective value of M2pπ3dΔ/M2pπ3dπ = -1.42 ± 0.01, which agrees well with the value of -1.35 ± 0.05 that we obtained earlier for transitions between similar triplet states of H2 and D2 and is close to the estimate of - √2 in the pure precession approximation, corresponds to the whole body of the measured rotational branching ratios of the molecules H2 and D2.

UR - http://www.scopus.com/inward/record.url?scp=17544368895&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:17544368895

VL - 80

SP - 34

EP - 39

JO - OPTICS AND SPECTROSCOPY

JF - OPTICS AND SPECTROSCOPY

SN - 0030-400X

IS - 1

ER -