A CALCULATION OF REPULSIVE FORCE CONSTANTS OF LENNARD-JONES POTENTIAL FOR SOME EXCITED STATES OF NOBLE GASES

Collision diameters and repulsive force constants of the Lennard-Jones potential are calculated for interactions between noble gas atoms, one of which is in an excited state. The excited-state atoms considered are neon (3s 2, 2p4, 1s2) and argon (2p2, 1s 2) (Paschen notation); the ground-state atoms are helium, neon and argon. It is shown that repulsive interactions between two atoms, one of which is in an excited state, are operative at much larger internuclear separations than those known for interactions between two unexcited atoms; the corresponding collision cross section for ground-state noble gas atom collisions is not at all representative when one of the interacting atoms is in an excited state.