The rotationally resolved H1u ← A0g± electronic spectrum of Hg2

Isotopically pure 202Hg vapor, contained in a quartz cell, was irradiated with the 2572.5 Å output from a frequency-doubled Ar+ laser, which produced Hg2 A0g± excimer molecules by photoassociation followed by collisional relaxation. Simultaneously applied probe radiation from a ring laser, scanned over the range 4150–4650 Å, gave rise to the H1u ← A0g+ and H1u ← A0g− 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.