Author/Authors :
R.R. and Hjelte، نويسنده , , I. and Piancastelli، نويسنده , , M.N. and Fink، نويسنده , , R.F. and Bjِrneholm، نويسنده , , O. and Bنssler، نويسنده , , M. and Feifel، نويسنده , , R. and Giertz، نويسنده , , A. and Wang، نويسنده , , H. and Wiesner، نويسنده , , K. and Ausmees، نويسنده , , A. and Miron، نويسنده , , C. M. Sorensen، نويسنده , , S.L. and Svensson، نويسنده , , S.، نويسنده ,
Abstract :
We present direct evidence for ultra-fast dissociation of molecular water in connection photo-excitation of the O1s→4a1 resonance. The core-excited H2O molecules are shown to dissociate into core-excited O*H and neutral H on a time scale comparable to the core hole lifetime, i.e. a few femtoseconds. This conclusion is based on a resonant Auger study, qualitative arguments and ab initio calculations. `Hot bandsʹ connected to Auger transitions from vibrationally excited OH fragments are identified, and these exhibit a dynamical behavior which qualitatively follows the change in excess energy.
