Canadian Journal of Physics

SENSITIZED FLUORESCENCE IN VAPORS OF ALKALI METALS: IX. ENERGY TRANSFER IN COLLISIONS BETWEEN SODIUM AND INERT GAS ATOMS

John M. Pitre, L. Krause

Published Aug 1, 1967• 69 citations

Abstract

The total cross sections for inelastic collisions between sodium and inert gas atoms, leading to 3 2P1/2 ↔ 3 2P3/2 excitation transfer in sodium, have been determined in a series of sensitized fluorescence experiments with sodium – inert gas mixtures. The sodium vapor was maintained at a pressure of 5 × 10−7 mm Hg, at which there is no trapping of the resonance radiation, and the inert gas pressures ranged from 0 to 1 mm Hg. The cross sections Q1(3 2P1/2 → 3 2P3/2) and Q2(3 2P1/2 ← 3 2P3/2) are as follows: Na–He, 86.0 and 44.8 Å2; Na–Ne, 67.0 and 35.4 Å2; Na–Ar, 110 and 55.9 Å2; Na–Kr, 85.0 and 43.6 Å2; Na–Xe, 89.8 and 45.6 Å2. The ratios Q1/Q2 are in agreement with the value predicted from the principle of detailed balancing and the cross sections also agree, as to order of magnitude, with some theoretically predicted values.

DOI: 10.1139/p67-216

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