Optical control of ground-state atomic orbital alignment: Cl({sup 2}P{sub 3/2}) atoms from HCl(v=2,J=1) photodissociation

Journal Article · Sun Oct 14 04:00:00 EDT 2007 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.2772272· OSTI ID:21024300

Sofikitis, Dimitris; Martin, Marion R; Ankeny Brown, Davida J; Bartlett, Nathaniel C.-M.; Alexander, Andrew J; Zare, Richard N; Rakitzis, T Peter ^[1]

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1. Institute of Electronic Structure and Laser, Foundation of Research and Technology-Hellas, 71110 Heraklion-Crete, Greece and Department of Physics, University of Crete, P.O. Box 2208, 71003 Voutes-Heraklion (Greece)

H{sup 35}Cl(v=0,J=0) molecules in a supersonic expansion were excited to the H{sup 35}Cl(v=2,J=1,M=0) state with linearly polarized laser pulses at about 1.7 {mu}m. These rotationally aligned J=1 molecules were then selectively photodissociated with a linearly polarized laser pulse at 220 nm after a time delay, and the velocity-dependent alignment of the {sup 35}Cl({sup 2}P{sub 3/2}) photofragments was measured using 2+1 REMPI and time-of-flight mass spectrometry. The {sup 35}Cl({sup 2}P{sub 3/2}) atoms are aligned by two mechanisms: (1) the time-dependent transfer of rotational polarization of the H{sup 35}Cl(v=2,J=1,M=0) molecule to the {sup 35}Cl({sup 2}P{sub 3/2}) nuclear spin [which is conserved during the photodissociation and thus contributes to the total {sup 35}Cl({sup 2}P{sub 3/2}) photofragment atomic polarization] and (2) the alignment of the {sup 35}Cl({sup 2}P{sub 3/2}) electronic polarization resulting from the photoexcitation and dissociation process. The total alignment of the {sup 35}Cl({sup 2}P{sub 3/2}) photofragments from these two mechanisms was found to vary as a function of time delay between the excitation and the photolysis laser pulses, in agreement with theoretical predictions. We show that the alignment of the ground-state {sup 35}Cl({sup 2}P{sub 3/2}) atoms, with respect to the photodissociation recoil direction, can be controlled optically. Potential applications include the study of alignment-dependent collision effects.

• OSTI ID: 21024300
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 14 Vol. 127; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CHLORINE 35
COLLISIONS
DISSOCIATION
EXCITATION
GROUND STATES
HYDROCHLORIC ACID
MASS SPECTROSCOPY
PHOTOLYSIS
POLARIZABILITY
POLARIZATION
SPIN
TIME DELAY
TIME DEPENDENCE
TIME-OF-FLIGHT METHOD