Eur. Phys. J. D 50, 141-151 (2008)
https://doi.org/10.1140/epjd/e2008-00204-2

Theoretical determination of the potassium far-wing photoabsorption spectra

¹ Physics Department, Badji Mokhtar University, B.P. 12, Annaba, 23000, Algeria
² Laboratoire de Physique des Rayonnements, Badji Mokhtar University, B.P. 12, Annaba, 23000, Algeria
³ Souk-Ahras University Center, Souk-Ahras, 41000, Algeria

Corresponding author: ^a boulmoncef@netscape.net

Received: 26 June 2008
Revised: 15 August 2008
Published online: 24 October 2008

Abstract

This theoretical work reports full quantum-mechanical analysis of the potassium far-wing photoabsorption spectra. The accuracy of the adopted K₂ potential-energy curves and transition dipole moments is established by computing the vibration-rotation levels and the radiative lifetimes of the excited molecular states and by determining the variation law with temperature of the diffusion coefficient of atomic K(4p) in a ground potassium gas. The pressure-broadening calculations revealed that the photoabsorption spectra have, in the temperature range 850-3000 K, a satellite structure characterized by the presence of three peaks around 718.7 nm in the blue wings and 1048.1 and 1100.8 nm in the red wings. This theoretical work could in particular point out the occurrence in the blue wing of a satellite originating from the bound-free B←X transitions near 731.5 nm. All these results agree quite well with the experimentally measured values.