PREDICTED STRUCTURE, SPECTRA AND STABILITY OF ARHX(+), KRHX(+) AND XEHX(+) (X=CL, BR OR I)

Results of effective core potential, ab initio calculations on the gro und state molecular properties of ArHX(+), KrHX(+) and XeHX(+) (X = Cl , Br or I) are presented. Calculations at the MP2, coupled cluster wit h double excitations and coupled cluster with single, double and tripl e excitations levels predict both linear and bent structures for these species. The obtained structures and their relative energies are well rationalized in terms of ionization energies of the individual atoms. The linear forms of XeHCl+ and XeHBr+ ions show strong, shared ''hydr ogen bond''-type bonding with a drastically reduced frequency of the h ydrogen motion between the heavy atoms. These ions are predicted to be stable and experimentally accessible under the conditions of low temp erature, matrix isolation experiments.