Summary: www.pubs.acs.org/accounts Vol. XXX, No. XX ' XXXX ' 000000 ' ACCOUNTS OF CHEMICAL RESEARCH ' A
10.1021/ar200076s & XXXX American Chemical Society
Liquid Water: From Symmetry Distortions to
The Fritz Haber Research Center, Institute of Chemistry, The Hebrew University of
Jerusalem, Jerusalem 91904, Israel
RECEIVED ON MARCH 8, 2011
C O N S P E C T U S
W ater deviates from tetrahedral symmetry on different scales, creating
"defects" that are important for its dynamics. In this Account,
I trace the manifestations of these distortions from the isolated molecule
through gas-phase clusters to the liquid phase.
Unlike the common depiction, an isolated water molecule has a nonsym-
metric charge distribution: although its positive charge is localized at the
hydrogens, the negative charge is smeared between the lone-pair sites.
This creates a "negativity track" along which a positive charge may slide.
Consequently, the most facile motion within the water dimer is a
reorientation of the hydrogen-bond (HB) accepting molecule (known as
an "acceptor switch"), such that the donor hydrogen switches from one