Shift of the Til 535.0 nm line by hydrogen

Abstract

The shift by hydrogen of the 535.0 nm T1 line resulting from photodissociation of thallium iodide was investigated at low densities. A linear variation of the shift with the hydrogen density was found with a shift coefficient of -(0.443 ± 0.012) X 10-20 cm-1 /(molecules cm-3).

Pressure Effects of Foreign Gases on the 535.0 nm Fluorescence Line of Thallium

“…The profile measurements on the 535 line reported in [1][2][3][4][5][6][7][8][9][10] were performed using a pressurescanned Fabry-Perot interferometer (spacer 1.204 cm, free spectral range 0.415 cm"') with a photoelectric detector as described in the papers by Bielski et al [19,20]. Details of our numerical analysis of the 535 line are described in [1] (cf.…”

“…(23) where v 0 is the unperturbed frequency and M the mass of the emitting atom. For the 535 line at the temperature 733 K, at which all measurements in [1][2][3][4][5][6][7][8][9][10] were performed, (23) yields yj th) = 0.025 cm" 1 .…”

“…Using the experimental values of collision broadening and shift coefficients ß and <5 measured in [1][2][3][4][5][6][7][8][9][10] (see Table 1) for various gases, the effective cross-sections Vo^/v and v ajv can be determined from (1) and (2) (24) where M is the mass of the emitting Tl-atom and m p is the mass of the perturber. Our values of the effective cross-sections Va h /v (th) and FA S /F (TH) determined from (1) and (2) using the values of R (TH) calculated from (24) are listed in Table 2.…”

“…In a series of experiments in this laboratory [1][2][3][4][5][6][7][8][9][10] the collision broadening and shift of the green fluorescence thallium line 535.0 nm (7 2 S 1/2 -6 ~P3/2) perturbed by various foreign gases have been studied at densities low enough (^4- 10 18 cm" 3 ) for the impact approximation to be valid. The main goal of these studies was to provide information about interactions between thallium atoms in the 7 2 S 1/2 and 6 2 P 3/2 states and various perturbing particles such as noble gas atoms [4,5], simple non-polar diatomic molecules H 2 [1,2], D 2 [3], N 2 [6], 0 2 [7] as well as the non-polar polyatomic molecules C0 2 [8] and SF 6 [9], Recently, the collision broadening and shift studies on the 535.0 nm TI line have been extended [10] by use of CO with its permanent electric dipole moment.…”

“…The main goal of these studies was to provide information about interactions between thallium atoms in the 7 2 S 1/2 and 6 2 P 3/2 states and various perturbing particles such as noble gas atoms [4,5], simple non-polar diatomic molecules H 2 [1,2], D 2 [3], N 2 [6], 0 2 [7] as well as the non-polar polyatomic molecules C0 2 [8] and SF 6 [9], Recently, the collision broadening and shift studies on the 535.0 nm TI line have been extended [10] by use of CO with its permanent electric dipole moment. Particular attention was paid to the analysis of the shape and shift of the line in order to obtain reliable values of the broadening and shift parameters.…”