Picosecond calorimetry: time-resolved x-ray diffraction studies of liquid CH2Cl2
Journal article, 2006

Liquid phase time-resolved x-ray diffraction with 100 ps resolution has recently emerged as a powerful technique for probing the structural dynamics of transient photochemical species in solution. It is intrinsic to the method, however, that a structural signal is observed not only from the photochemical of interest but also from the embedding solvent matrix. To experimentally characterize the x-ray diffraction signal deriving from the solvent alone we performed time-resolved diffraction studies of a pure liquid sample over a time domain from -250 ps to 2.5 μs. Multiphoton excitation was used to rapidly heat liquid C H2 Cl2 using UV pulses of 100 fs duration. A significant x-ray diffraction signal is visible prior to the onset of thermal expansion, which characterizes a highly compressed superheated liquid. Liquid C H2 Cl2 then expands as a shock wave propagates through the sample and the temporal dependence of this phenomenon is in good agreement with theory. An unexpectedly slow initial release of energy into the liquid as heat is observed from multiphoton excited C H2 Cl2, revealing the presence of a metastable state of multiphoton excited C H2 Cl2. © 2006 American Institute of Physics.

Author

P Georgiou

Uppsala University

J Vincent

Uppsala University

Magnus Andersson

Chalmers, Chemical and Biological Engineering, Molecular Biotechnology

Annemarie Wöhri

Chalmers, Chemical and Biological Engineering, Molecular Biotechnology

Pontus Emanuel Gourdon

Chalmers, Chemical and Biological Engineering, Molecular Biotechnology

Jens Aage Poulsen

University of Gothenburg

J Davidsson

Uppsala University

Richard Neutze

Chalmers, Chemical and Biological Engineering, Molecular Biotechnology

Journal of Chemical Physics

0021-9606 (ISSN) 1089-7690 (eISSN)

Vol. 124 23 234507-

Subject Categories

Industrial Biotechnology

DOI

10.1063/1.2205365

More information

Latest update

2/28/2018