"Growth of Li-B nanocrystals on the Surface of LiF Laser Crystal at 60Co Gamma-Irradiation"

Abstract

This work was aimed at studying structure-phase transformations in passive laser Q-switch made of LiF:OH, interfaces and nanoparticles, grown at exposure to isotropical 60Coγ-quanta flux to the doses 107-108 R, combining SEM, SPM, XRD, UV-vis and FTIR techniques. The origin crystal contains Li and LiH nanophases, and after the irradiation at 273 K low symmetric LiBH phases with larger lattice parameters can grow only on the surface as separated hillocks, while at 320 K atom diffusion allows to assemble a wall of these phases. Optical spectra contain both absorption and scattering centers with the ratio depending on the irradiation temperature. Oxygen could have come from air. The only origin of so many atoms of B and H and more Li is a special nuclear branching decay 19F9+γ→11B5+7Li3+1H1 under absorption of 1.17 and 1.33 MeV γ-quanta by F-nuclei. Another way is nuclear compound transmutation 13(НLiF)27+ γ→13(ВО)27→ 5B11 + 8O16