• Gavrila, G.; Godehusen, K.; Weniger, C.; Nibbering, E.T.J.; Elsaesser, T.; Eberhardt, W.; Wernet, P.: Time-resolved X-ray absorption spectroscopy of infrared-laser induced temperature jumps in liquid water. Applied Physics A 96 (2009), p. 11-18

10.1007/s00339-009-5190-6
Open Access Version

Abstract:
A time-resolved X-ray absorption study of the structural dynamics of liquid water on a picosecond timescale is presented. We apply femtosecond midinfrared pulses to resonantly excite the intramolecular O–H stretching band of liquid water and monitor the transient response in the oxygen K-edge absorption spectrum with picosecond X-ray pulses. In this way, structural changes in the hydrogen bond network of liquid water upon an ultrafast temperature jump of approximately 20 K are investigated. The changes of the X-ray absorption as induced by such a temperature jump are about 3.2%. This demonstrates that our method serves as a sensitive probe of transient structural changes in liquid water and that combined infrared-laser–synchrotron experiments with substantially shorter X-ray pulses, such as generated with a femtosecond slicing scheme, are possible.