Accession Number : AD0661856

Title :   ESR AND OPTICAL STUDIES OF O2(-) IN NAF.

Descriptive Note : Technical rept.,

Corporate Author : CORNELL UNIV ITHACA N Y MATERIALS SCIENCE CENTER

Personal Author(s) : Meistrich,M. L.

Report Date : OCT 1967

Pagination or Media Count : 31

Abstract : The O2(-) molecule-ion was observed as an impurity in single crystals of sodium fluoride. The ion was produced principally by room temperature x-irradiation of NaF doped with OH(-) ions. The O2(-) ion was identified by its ESR spectrum, observed at liquid helium temperatures. The g-tensor for the resonance has approximate axial symmetry about the molecular axis, with g-parallel = 2.97 and g-perp. = 1.41. In crystals containing isotopically enriched oxygen, the hyperfine interaction with the O17 nucleus was measured. A qualitative comparison of the ESR parameters of O2(-) in NaF with the determinations of the electronic structure of O2(-) in other alkali halides is made. The large G-shifts and the appreciable perturbation of the O2(-) molecular orbitals in the small NaF lattice make a quantitative treatment difficult. Optical studies of O2(-) in NaF were made. No absorption band in the near ultraviolet, nor fluorescence excited in that region, could be detected. An absorption at 8.7 ev was assigned to a charge-transfer band of O2(-). Several other paramagnetic defects, probably associated with oxygen, were also formed in the course of the x-ray production of O2(-). Their spin resonance patterns were studied but no identification was made. (Author)

Descriptors :   (*FLUORIDES, CRYSTAL DEFECTS), (*CRYSTAL DEFECTS, OXYGEN), (*OXYGEN, *ELECTRON PARAMAGNETIC RESONANCE), SODIUM COMPOUNDS, SINGLE CRYSTALS, IMPURITIES, SPECTROSCOPY, HYPERFINE STRUCTURE, MOLECULAR ORBITALS, CRYSTAL LATTICES, ULTRAVIOLET SPECTRA, VISIBLE SPECTRA, FLUORESCENCE, ABSORPTION SPECTRA, COLOR CENTERS

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE