M. Kibler, MULTIPHOTON LASER SPECTROSCOPY OF TRANSITION IONS IN CRYSTALS - RECENT PROGRESS IN THE USE OF SYMMETRY CONSIDERATIONS, Laser physics, 4(1), 1994, pp. 38-40
The role of symmetry adaptation techniques in multiphoton spectroscopy
of partly filled shell ions in crystals is briefly reviewed. This lea
ds to an intensity formula that is discussed from a qualitative point
of view.