Nonadiabatic representation for the i 3Πg--j 3Δg- complex of H2 and D2 -: art. no. 052501

The full nb initio nonadiabatic approach was successfully applied to calculate energy, radiative, and magnetic properties of strong L-uncoupling i (3)Pi(g)(-) and j (3)Delta(g)(-) states of molecular hydrogen isotopes, for the first rime, to our knowledge. The concomitant electronic L-uncoupling matrix elements between the i (3)Pi(g) and j (3)Delta(g) as well as the i (3)Pi(g)-b (3)Sigma(u)(+), i (3)Pi(g)-e (3)Sigma(u)(+), i (3)Pi(g)-c (3)Pi(u), and j (3)Delta(g)-c (3)Pi(u) transition dipole moment functions were revised by using an electronic full configuration-interaction calculation together with highly accurate ab initio adiabatic potentials taken from the literature. The ab initio results were borne out by quantum-defect theory estimates. Nonadiabatic rovibronic eigenvalues and eigenfunctions for the bound i (3)Pi(g)(-) -j (3)Delta(g)(-) perturbation complex were derived by direct numerical solutions of the two channel-coupling radial equations. The theoretical term values of the complex for H-2 and D-2 agree with their experimental counterparts within 0.5-1.5 cm(-1). For the overwhelming majority of levels, the calculated magnetic g factors coincide with the measured ones within their experimental accuracy. The predicted rovibronic transition probabilities to the lower-lying b (3)Sigma(u)(+) c (3)Pi(u), and e (3)Sigma(u)(+) states completely resolve perplexing problems of the radiative data in experiments: lifetimes, branching ratios of fluorescence decay to the b (3)Sigma(u)(+) and c (3)Pi(u)(+) states, and the intensity distribution in rotational structure of the i (3)Pi(g)(-)-j (3)Delta(g)(-)-->c (3)Pi(u)(+/-) transitions.