Femtosecond spectroscopy in an extended spectral range of up to 5.5 mum is
demonstrated of a water (D2O) sample after two photon excitation at 9.1 eV.
The data provides clear evidence for two short-lived precursors of the hyd
rated electron previously not identified. The first novel precursor determi
ned here with peak absorption at 2.9 (4.1) mum is proposed to represent an
OH(D):e(-) complex. The subsequent solvation proceeds via e(-):((H,D)(2)O)(
n) complexes at approximately 1.6 (2.0) mum in the electronic ground state.
An increasing number of water molecules are involved in the built up of th
e trap around the photogenerated electron during the first 200 fs. (C) 2001
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