Laser excited, state detected calcium-rare gas collisional energy transfer: Ca(4s5p /sup 1/P/sub 1/) spin changing and Ca(4s5p /sup 3/P/sub 1/) fine structure changing cross sections

Journal Article · Sat Oct 01 00:00:00 EDT 1983 · J. Chem. Phys.; (United States)

OSTI ID:5592935

Hale, M O; Leone, S R

Pulsed dye laser excitation along with time and wavelength-resolved fluorescence detection techniques are used to measure cross sections for state changing collisions of Ca(4s5p /sup 1/P/sub 1/) and Ca(4s5p /sup 3/P/sub 1/) with the rare gases He, Ne, Ar, Kr, and Xe. The Ca(4s5p /sup 1/P/sub 1/)+M deactivation involves a near-resonant spin changing process which populates predominantly the Ca(4s5p /sup 3/P/sub 2,1,0/) states. The total deactivation cross sections for /sup 1/P/sub 1/ are 22, 25, 5, 3, 13, and 31 A/sup 2/ ( +- 20%) for /sup 3/He, /sup 4/He, Ne, Ar, Kr, and Xe, respectively. The cross sections for Ca(4s5p /sup 3/P/sub 1/)+M fine-structure changes are 38, 25, 46, 56, and 135 A/sup 2/ ( +- 35%) for He, Ne, Ar, Kr, and Xe, respectively. Branching ratios for the electronic energy transfer Ca(4s5p /sup 1/P/sub 1/)+Hearrow-right-leftCa(4s5p /sup 3/P/sub j/, 3d4p /sup 3/F/sub j/, and 3d4p /sup 1/D/sub 2/)+He are determined to be 90 +- 3:6 +- 4:3 +- 2, respectively, compared to statistical values of 26:60:14. The predominant product states 4s5p/sup 3/P/sub 2,1,0/ are produced by a near-resonant spin changing process; the fine structure components of the /sup 3/P state are populated essentially statistically (55:33:11).

• Research Organization: Joint Institute for Laboratory Astrophysics, National Bureau of Standards and University of Colorado, Department of Chemistry, University of Colorado, Boulder, Colorado 80309
• OSTI ID: 5592935
• Journal Information: J. Chem. Phys.; (United States), Vol. 79:7
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ARGON
ATOM-ATOM COLLISIONS
CALCIUM
HELIUM
KRYPTON
NEON
XENON
ELECTRONIC STRUCTURE
ENERGY TRANSFER
FINE STRUCTURE
SPIN
TOTAL CROSS SECTIONS
ALKALINE EARTH METALS
ANGULAR MOMENTUM
ATOM COLLISIONS
COLLISIONS
CROSS SECTIONS
ELEMENTS
FLUIDS
GASES
METALS
NONMETALS
PARTICLE PROPERTIES
RARE GASES
640304* - Atomic
Molecular & Chemical Physics- Collision Phenomena