Structure and dynamics of small water clusters, trapped in inert matrices

Recent matrix isolation (p-H2, Ne, Ar, Kr) studies of water clusters made in Lund are reviewed. Gas phase positions of water cluster bands are estimated from matrix data. Intermolecular spectra of several isotopomers of the water dimer have been obtained, and approximate band strengths have been measured. Acceptor switching of the water dimer has been observed in matrices. A few intermolecular vibrations of (H2O)3, (D2O)3, (H2O)4, and (D2O)4 have been measured. The pseudorotation of the water trimer is not quenched in matrices, and pentamer pseudorotation appears to be fast as well. Spectra of partially deuterated water tetramers support a rigid cyclic tetramer structure. The hydrogen rotation in p-H2 may interfere with guest vibrations at frequencies near the J = 2 ← J = 0 band of solid parahydrogen.