MD-DIM simulations of the 3Πg(ion-pair)→3Πu(valence) red-shifted transitions of Cl2 in neon matrices

The mixed quantum-classical molecular dynamics (MD) calculations with the diatomics-in-molecules (DIM) interaction potentials have been performed to model the features of the emission spectral bands corresponding 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 corresponding cuts through the Cl-2 @ Ne-n multi-dimensional potential energy 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 simulations 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.