Direct absorption spectra of jet‐cooled Hg2

The electronic absorption spectrum of the van der Waals dimer Hg2 has been measured in the UV–spectral range by a new supersonic jet direct absorption technique. The data led to an improved analysis of the X 10+g–G 10+u transition, yielding the parameters ω’e =79 cm−1, ωex’e =0.22 cm−1, and Re =3.00 A for the Morse potential of the G 10+u state.