Studies of the electronic transitions of the n = 1 (1P1, 3P1 - 1S0) exciton in solid rare gases at different vols. can yield valuable information about intermol. potentials. A computer calcn. of the absorption and emission energies of solid Ne was performed; the effect of pressure shifts the lines to higher energies. The results at zero pressure stress the importance of zero point motion in a Ne crystals and the need for improved potential curves. [on SciFinder (R)]