TY - JOUR

T1 - Hyperfine coupling and large amplitude motions interaction in the water dimer

AU - Coudert, L. H.

AU - Caminati, W.

AU - Schnell, M.

AU - Grabow, J. U.

N1 - Funding Information: The authors are very grateful to Prof. Jean-Marie Flaud for critically reading the manuscript. Funding by the Deutsche Forschungsgemeinschaft (DFG) and the Land Niedersachsen is gratefully acknowledged. J.-U.G. and W.C. thank the Deutsche Akademische Austauschdienst (DAAD) and the Ministero dell’Instruzione, dell’Universita e della Ricerca (MIUR) for support within the bilateral Project PPP D/0231300 and VIGONI 2003 21-2002, respectively.

PY - 2007/4

Y1 - 2007/4

N2 - Experimental and theoretical analyses of the hyperfine structure of the non-rigid water dimer (H2O)2 were carried out. Measurements were performed with an FT-MW spectrometer allowing us to resolve most of the hyperfine components. Eight hyperfine patterns were recorded involving rotational-tunneling sublevels with J ≤ 2. Hyperfine patterns were analyzed accounting for the magnetic spin-rotation and spin-spin hyperfine couplings. Symmetry adapted nuclear spin wavefunctions were built to account for the interaction of the hyperfine coupling with the large amplitude motions displayed by the water dimer and to build total rotational-tunneling-hyperfine wavefunctions obeying the Pauli exclusion principle. This accounts for the strong dependence of the hyperfine patterns on the symmetry species of the rotational-tunneling sublevels. These theoretical results were used to perform individual and global analyses of the hyperfine patterns. The latter analysis yields values for some of the components of the spin-rotation coupling tensors.

AB - Experimental and theoretical analyses of the hyperfine structure of the non-rigid water dimer (H2O)2 were carried out. Measurements were performed with an FT-MW spectrometer allowing us to resolve most of the hyperfine components. Eight hyperfine patterns were recorded involving rotational-tunneling sublevels with J ≤ 2. Hyperfine patterns were analyzed accounting for the magnetic spin-rotation and spin-spin hyperfine couplings. Symmetry adapted nuclear spin wavefunctions were built to account for the interaction of the hyperfine coupling with the large amplitude motions displayed by the water dimer and to build total rotational-tunneling-hyperfine wavefunctions obeying the Pauli exclusion principle. This accounts for the strong dependence of the hyperfine patterns on the symmetry species of the rotational-tunneling sublevels. These theoretical results were used to perform individual and global analyses of the hyperfine patterns. The latter analysis yields values for some of the components of the spin-rotation coupling tensors.

KW - Hyperfine structure

KW - Large amplitude motion

KW - Magnetic hyperfine coupling

KW - Microwave spectrum

KW - Rotational spectrum

KW - Spin-rotation coupling

KW - Spin-spin coupling

KW - Supersonic-jet expansion

KW - Water dimer

UR - http://www.scopus.com/inward/record.url?scp=34250322238&partnerID=8YFLogxK

U2 - 10.1016/j.jms.2007.02.014

DO - 10.1016/j.jms.2007.02.014

M3 - Article

AN - SCOPUS:34250322238

VL - 242

SP - 118

EP - 128

JO - Journal of molecular spectroscopy

JF - Journal of molecular spectroscopy

SN - 0022-2852

IS - 2

ER -