TY  - JOUR
AU  - Pedersen, H. B.
AU  - Domesle, C.
AU  - Lammich, L.
AU  - Dziarzhytski, S.
AU  - Guerassimova, N.
AU  - Treusch, R.
AU  - Harbo, L. S.
AU  - Heber, O.
AU  - Jordon-Thaden, B.
AU  - Arion, T.
AU  - Förstel, M.
AU  - Stier, M.
AU  - Hergenhahn, U.
AU  - Wolf, A.
AU  - DESY
TI  - Photolysis of water-radical ions H<sub>2</sub>O<sup>+</sup> in the xuv: Fragmentation through dicationic states
JO  - Physical review / A
VL  - 87
IS  - 1
SN  - 1050-2947
CY  - College Park, Md.
PB  - APS
M1  - PHPPUBDB-23710
SP  - 013402
PY  - 2013
AB  - The photofragmentation of the water cation H<sub>2</sub>O<sup>+</sup> through dicationic states has been studied at 35.0 ± 0.2 nm (35.4 ± 0.3 eV) and 21.8 ± 0.2 nm (56.8 ± 0.5 eV) with a crossed ion-photon beams experiment at the free electron laser FLASH. The dissociation of the dications is found to be similar at the two wavelengths and to proceed into O<sup>0</sup> + 2H<sup>+</sup>, OH<sup>+</sup> + H<sup>+</sup>, and O<sup>+</sup> + H<sub>2</sub><sup>+</sup>, with determined ratios σ<sub>OH<sup>+</sup> + H<sup>+</sup></sub>/σ<sub>O<sup>+</sup> + H<sub>2</sub><sup>+</sup></sub>= 4.2 ±0.3 and σ<sub>OH<sup>+</sup> + H<sup>+</sup></sub>/σ<sub>O<sup>+</sup> + 2H<sup>+</sup></sub>>0.7. The measured kinetic-energy releases for these processes are consistent with three-body breakup (O<sup>0</sup>+2H<sup>+</sup>) occurring mainly through the 2<sup>3</sup>A" and 2<sup>1</sup>A" states of H<sub>2</sub>O<sub>2</sub><sup>+</sup> and two-body breakup (OH<sup>+</sup> + H<sup>+</sup>) occurring through X<sup>3</sup>A", 1<sup>3</sup>A′, and 1<sup>1</sup>A" states of H<sub>2</sub>O<sub>2</sub><sup>+</sup>, as predicted in a recent theoretical study [Gervais et al., J. Chem. Phys. 131, 024302 (2009)]. In addition to the kinetic-energy releases, we also report on fragment correlation in the three-body channel where the two protons carry the major part of the released momentum.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000312994700010
DO  - DOI:10.1103/PhysRevA.87.013402
UR  - https://bib-pubdb1.desy.de/record/139445
ER  -