Progress in theoretical studies of physical phenomena in high-power light sources

Summary form only given. Some high-power light sources operate on mixture of mercury and small amounts of rare earth halides molecules LnX (Ln/spl equiv/Dy, Ho, Tm, X/spl equiv/I, Br). Such sources have high output (radiative) power, but their frequency spectrum is often quite different from the (usually) desired solar spectrum. Lack of reliable thermodynamic and/or kinetic models of the plasmas in the devices makes understanding, and subsequently controlability, of the spectrum very difficult. We discuss in this work partition functions and thermodynamic functions of partially-ionized monoatomic (Hg, Dy, Ho and Tm) and diatomic (DyI, HoI, TmI, DyBr, HoBr and TmBr) gases which are typical components of plasmas used in the light sources discussed here.