Foreign gas broadening

Foreign gas broadening of HCl. Measured values of the reciprocal dephasing time l/l2,Ar versus rotational quantum number of the vibration-rotation transition ( ) corresponding linewidth scale for IR-linewidth data (hatched rect-... 

L Galatry. Simultaneous effect of Doppler and foreign gas broadening on spectral lines. Phys Rev 122 1218-1223, 1961. 

However, when the broadening of krypton by other noble gases was examined, widely different temperature coefficients and width-to-shift ratios were obtained. This confirmed a conclusion reached earlier by Smith (1967) an adequate theory of foreign gas broadening in the impact approximation requires the use of a potential containing both attractive and repulsive components. Unfortunately such potentials are extremely difficult to calculate theoretically, nor is it possible to unambiguously derive an empirical potential,... 

It has been shown [Mitchell and Zemansky (21), p. 197] that the quenching of the Hg 2537 A line by foreign gases follows the Stcrn-Volmer formula only when (1) Lorent/ broadening [see. Section 1-6.1] by foreign ga.ses is... 

The broadening of spectral lines can be due to Doppler effects, foreign gas, or resonance effects. Doppler broadening is due to the random motion of atoms. The atoms move in different directions and... 

The collisional broadening in a monatomic gas is characterized by values of cr of the order of (1-5) x 10 cm. If the perturbing particles are atoms or molecules of a foreign gas, then typically a 10 -10 cm. A similar mechanism of broadening occurs also for vibrational and rotational transitions in molecules. The corresponding cross-sections are much less, about (1-3) x 10 cm. ... 

In the assessment of the strength of the surface field from observations of a bathochromic shift, it must be kept in mind that any influence which causes a broadening and coalescence of the line components of a structured absorption band of a gaseous molecule, e.g., the mere addition of a foreign inert gas, enhances the averaged absorbance in this region, leaving an already present continuous portion of the spectrum unaffected 26, 28),... 

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