MD-DIM SIMULATIONS OF THE (3)PI(G)(ION-PAIR)-](3)PI(U)(VALENCE) RED-SHIFTED TRANSITIONS OF CL-2 IN NEON MATRICES

The mixed quantum-classical molecular dynamics (MD) calculations with the diatomics-in-molecules (DIM) interaction potentials have been perf ormed to model the features of the emission spectral bands correspondi ng to the transition from the ion-pair (3)Pi(g) state to the valence ( 3)Pi(u) State of Cl-2 in neon matrices. The matrix-perturbed potential curves of the trapped Cl-2 molecule have been evaluated as the corres ponding cuts through the Cl-2 @ Ne-n multi-dimensional potential energ y surfaces and the numerical calculations of the (3)Pi(g)(upsilon') -- > 3 Pi(u)(upsilon'') band positions and the Franck-Condon factors have been estimated along classical trajectories. The results of the simul ations show a remarkable resemblance to earlier experimental findings; namely, the matrix environment causes red shifts in the (0, upsilon ' ') band positions as well as noticeable changes in band intensities. ( C) 1998 Elsevier Science B.V. All rights reserved.