THEORETICAL-STUDY OF THE STRUCTURE AND VIBRATIONAL-SPECTRA OF THE (H2O)2...HF AND H2O...(HF)2 MOLECULAR-COMPLEXES

Using the Hartree-Fock and MP2 methods with bases of up to 6-31++G(2d, 2p) quality, the optimum geometry of the 1:2 and 2:1 (H2O)n ... (HF)m complexes of water and hydrogen fluoride is searched in a systematic way. Two minimum-energy conformations are found for the 1:2 complex co nnected through a low-energy transition state. For the 2:1 complex, on ly one minimum-energy structure is obtained. The analysis of the geome tries of the minima and their vibrational frequencies shows that none of them can be used to explain the existence of the H ... F-H reverse complex detected experimentally. (C) 1994 John Wiley & Sons, Inc.