We report on the experimental and theoretical study of qusimolecular emission near the forbidden atomic line Hg(6³P₂-6¹S₀) in a mixture of mercury vapor with argon. The experimental profile is a continuous band in the range 2230 - 2275 Å with a maximum at about 2255 Å. By using the semiempirical method of quasimiolecular term analysis and available experimental potential curves the interaction potentials of the excited atoms Hg∗ + Ar and the probabilities of the radiative transitions are determined. Based on them quasimolecular emission spectra are calculated.