Probing the hydrogen-bond network of water via time-resolved soft X-ray spectroscopy.
We report time-resolved studies of hydrogen bonding in liquid H(2)O, in response to direct excitation of the O-H stretch mode at 3 mum, probed via soft X-ray absorption spectroscopy at the oxygen K-edge. This approach employs a newly developed nanofluidic cell for transient soft X-ray spectroscopy in the liquid phase. Distinct changes in the near-edge spectral region (XANES) are observed, and are indicative of a transient temperature rise of 10 K following transient laser excitation and rapid thermalization of vibrational energy. The rapid heating occurs at constant volume and the associated increase in internal pressure, estimated to be 8 MPa, is manifested by distinct spectral changes that differ from those induced by temperature alone. We conclude that the near-edge spectral shape of the oxygen K-edge is a sensitive probe of internal pressure, opening new possibilities for testing the validity of water models and providing new insight into the nature of hydrogen bonding in water.
Huse
Nils
N
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. nhuse@lbl.gov
Wen
Haidan
H
Nordlund
Dennis
D
Szilagyi
Erzsi
E
Daranciang
Dan
D
Miller
Timothy A
TA
Nilsson
Anders
A
Schoenlein
Robert W
RW
Lindenberg
Aaron M
AM
D000042:Absorption; D006860:Hydrogen Bonding; D011312:Pressure; D013059:Spectrum Analysis, Raman; D013696:Temperature; D013997:Time Factors; D014732:Vibration; D014867:Water / Q000737:chemistry*; D014965:X-Rays
D014867:Water