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NMR Chemical Shifts of Ice and Liquid Water: The Effects of Condensation

Bernd G. Pfrommer,^† Francesco Mauri,^‡ and Steven G. Louie*^†

Contribution from the Department of Physics, University of California at Berkeley, Berkeley, California 94720, and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Laboratoire de Minralogie-Cristallographie de Paris, Universits P6 et P7, CNRS, case 115, 4 place Jussieu, 75252 Paris, France

J. Am. Chem. Soc., 2000, 122 (1), pp 123–129

DOI: 10.1021/ja991961k

Publication Date (Web): December 21, 1999

†

University of California at Berkeley and Lawrence Berkeley National Laboratory.

‡

Laboratoire de Minéralogie-Cristallographie de Paris.

In papers with more than one author, the asterisk indicates the name of the author to whom inquiries about the paper should be addressed.

Abstract

We report the results of ab initio density functional theory calculations of the NMR chemical shift of liquid water and hexagonal ice. Depending on the structural model used, the calculated isotropic shift of ice Ih with respect to the gas phase is −8.0 ± 0.2 or −8.1 ± 0.1 ppm for the proton, and −48.6 ± 0.02 or −48.1 ± 0.02 ppm for oxygen. The proton anisotropy is −33.4 ± 0.2 or −33.6 ± 0.2 ppm. Using snapshots from ab initio molecular dynamics simulations, we find a gas-to-liquid shift of −5.8 ± 0.1 ppm for hydrogen, and −36.6 ± 0.5 ppm for oxygen. Molecules beyond the first solvation shell influence the proton chemical shift predominantly via the electric field generated by their permanent electric dipole moment. Finally, we show that it is possible to reproduce the proton chemical shifts in the condensed phases by an empirical function of the local molecular geometry.

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