The structure of floppy molecules:: the Rg•XH/D (Rg = Ar, Ne, and Kr, X = O or S) family of complexes

The "structure" of Rg . XH/D weakly bound complexes, where Rg = Ne, Ar and Kr and X = O or S is reviewed. These species likely constitute the most thoroughly studied, broad family of complexes. Due to the open shell nature of OH and SH, the bonding in these complexes ranges from quite weak to incipient chemical. Most of the experimental data concerning these species come from the rotational and vibrational structure of the electronic transition, (A) over tilde(2)Sigma(+)-(X) over tilde(2)Pi(3/2). Based on the spectral work, empirical potential surfaces for both the (X) over tilde(2)Pi(3/2) and (A) over tilde(2)Sigma(+) states of the complexes have been developed. These potentials can be used to illustrate the structure and bonding of the complexes. They also can be used to elucidate observed dynamical processes in the complexes. (C) 2000 Elsevier Science B.V. All rights reserved.