Theoretical investigation of the lithium 2p ← 2s photoabsorption spectra perturbed by atomic hydrogen

This work proposes a theoretical study of the Li(2p <- 2s) photoabsorption spectra perturbed by ground hydrogen atoms. The temperature effect on the far-wing spectra is examined in the temperature range 4000-20 000 K. For this purpose, the ground and excited LiH potential curves and the transition dipole moments that connect them are constructed from ab initio data. The investigation shows that the profile spectra are dominated at all temperatures by the singlet A <- X transitions and exhibit in the red wing a satellite structure near the wavelength 1000 nm. The spectra revealed also the appearance beyond 14 000 K of a second satellite structure in the blue wing close to the wavelength 510 nm originating from the triplet c <- a transitions.