Resonance-enhanced one- and two-photon ionization of water molecule: Preliminary analysis by multichannel quantum defect theory
- Chemical Sciences Division, Lawrence Berkeley Laboratory, and Department of Chemistry, University of California at Berkeley, Berkeley, California 94720 (United States)
- Department of Theoretical Chemistry, University of Oxford, 5 South Parks Road, Oxford OX1 3UB (United Kingdom)
Experimental results are presented for one- and two-photon ionization of the water molecule, obtained using a near transform-limited xuv laser. The single-photon ionization results show rotationally resolved autoionizing resonances corresponding to members of Rydberg series ([ital nd][l arrow]1[ital b][sub 1]; [ital n]=6--11) converging on the H[sub 2]O[sup +](100) vibrational state. The two-color (1+1) multiphoton ionization results show rotationally resolved structure corresponding to Rydberg series ([ital nd][l arrow]1[ital b][sub 1]; [ital n][ge]6) converging on the H[sub 2]O[sup +](000) vibrational state. Typical linewidths below and above the H[sub 2]O[sup +](000) ionization threshold are 1 and 2 cm[sup [minus]1], respectively. The experimental results are simulated by multichannel quantum defect theory (MQDT). The main features in the spectrum are reproduced in a treatment of the rotational channel interactions with partial [ital l] mixing. It is argued that remaining discrepancies between experiment and theory arise from perturbative interactions between the ([ital nd][l arrow]1[ital b][sub 1]) levels and members of the ([ital nd][l arrow]3[ital a][sub 1]) Rydberg series. Also, it is argued that in the (1+1) multiphoton ionization spectra lines may be missing due to selective predissociation.
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 6942092
- Journal Information:
- Journal of Chemical Physics; (United States), Vol. 98:3; ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
Similar Records
Autoionization structure and rotational contours in the multiphoton ionization spectrum of carbon dioxide
Rotationally resolved pulsed field ionization photoelectron study of CO[sup +](X[sup 2][Sigma][sup +],v[sup +]=0[endash]42) in the energy range of 13. 98[endash]21. 92 eV
Related Subjects
WATER
PHOTOIONIZATION
AUTOIONIZATION
EXTREME ULTRAVIOLET RADIATION
LASERS
MULTI-PHOTON PROCESSES
QUANTUM MECHANICS
RESOLUTION
RESONANCE
ROTATIONAL STATES
SIMULATION
VIBRATIONAL STATES
ELECTROMAGNETIC RADIATION
ENERGY LEVELS
EXCITED STATES
HYDROGEN COMPOUNDS
IONIZATION
MECHANICS
OXYGEN COMPOUNDS
RADIATIONS
ULTRAVIOLET RADIATION
664200* - Spectra of Atoms & Molecules & their Interactions with Photons- (1992-)