Molecular hydrogen 3s,d 3Λg+ complex revisited

Abstract

The rovibronic term values, Landé factors, and radiative properties of all bound levels in the 3s,d 3Λg+ complex of H2, D2, and HD are evaluated in the framework of fully ab initio channel-coupling approach. The modified multichannel quantum-defect theory is employed to transform highly accurate ab initio Born–Oppenheimer electronic matrix elements borrowed from a literature to their diabatic counterparts avoiding explicit consideration of radial coupling effects. The radiative lifetimes of the most critical levels in the H2 complex are remeasured by a delayed coincidence method. The accuracy of the predicted term values, Landé factors, transition probabilities and experimental lifetimes is sufficient to indicate the sources of disagreement in existing theory and experimental data.

Rotational analysis of the molecular hydrogen triplet 3s,dcomplex revisited

“…[3], Ross and Jungen [4], and Pazyuk et al [5]. We have corrected the wrong assignments given in the literature [1,2] values agree with the previously calculated ones [3,4,5].…”

“…calculation approaches. It can be seen that there is a good agreement between our observations and the calculations, in particular for the observed rovibronic energies of v = 2 and 3 of "o -c" 's of about -50 cm -1 and -90 cm -1 in[3,4,5]. The strongest discrepancy (+ 16.2 cm -1 ) occurs for the level N = 5 of v = 2, energies of[4] resulting from ab initio MQDT calculations.…”

“…The three columns "o -c" of table I show the differences between the observed energies resulting from the analysis of this work and the calculated energies of [3], [4] and [5] . Our assignment work has been highly facilitated by the previous analysis of Dieke [1], Alikacem and Larzillière [2], and of Jungen et al [14], and also by the calculations [3,4,5] .55 cm -1 respectively. They also determined Q(1) and Q(3) of the band 4 -4 of the same electronic transition to be at 16729 and 16731 cm -1 respectively.…”

“…We also thank the French research program P. C. M. I. for partial financial support. [3,4,5] for the hydrogen n=3 triplet gerade complex; all the energies are given in cm -1 relative to the J=0, v=0 level of the 119348.13…”