PERTURBED STRUCTURE OF MOLECULAR-HYDROGEN NEAR THE 2ND DISSOCIATION LIMIT

The region of the second dissociation limit of H2 converging to H(1s) + H(2s, 2p) has been investigated using high-resolution double-resonance spectroscopy through the E, F1-SIGMA-g+ state. Transitions to the very high vibrational levels of the B1-SIGMA-u+, B'1-SIGMA-u+, and C1-PI-u states have been measured with 0.02-cm-1 accuracy. Numerous perturbations and unexpected transitions are observed as far as 10 cm-1 below the dissociation limit. This complex structure, still not fully understood, arises from a combination of electronic, fine-structure, and hyperfine interactions.