The rotationally resolved H1u ← A0g± electronic spectrum of Hg2

Isotopically pure 202 Hg vapor, contained in a quartz cell, was irradiated with the 2572.5 A output from a frequency-doubled Ar + laser, which produced Hg 2 A0 g ± excimer molecules by photoassociation followed by collisional relaxation. Simultaneously applied probe radiation from a ring laser, scanned over the range 4150–4650 A, gave rise to the H1 u ← A0 g + and H1 u ← A0 g − excitation spectra consisting of several hundred rotational components. Two previously unobserved rovibronic bands (one in each spectrum) were subjected to a rotational analysis which yielded spectroscopic constants that are compared with some previously reported values.