Electronic structure of beryllium fluoride

Journal Article · Tue Feb 15 00:00:00 EST 1983 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.27.2446· OSTI ID:6060988

Bedford, K L; Williams, R T; Hunter, W R; Rife, J C; Weber, M J; Kingman, D D; Cline, C F

Vacuum-ultraviolet reflectance, absorptance, and photoelectron spectroscopy of vitreous and crystalline BeF/sub 2/ are reported. The data are interpreted with reference to self-consistent unrestricted Hartree-Fock cluster calculations also presented in this paper. The first allowed exciton reflectance peak in crystalline BeF/sub 2/ is at 12.9 eV, similar to the 12.8-eV peak found in the glass. Optical transmission of bulk samples extends at least to 9.5 eV, and can be assumed to be impurity limited in available material. Calculations of several defect and impurity levels are presented. Since the calculations presented here indicate that BeF/sub 2/ should have an optically forbidden band edge similar to that in SiO/sub 2/, the ultimate transparency range of purified BeF/sub 2/ will depend on the forbidden exciton absorption, not yet observable above the impurity background. Grazing-incidence reflectance spectra near the Be/sup 2 +/ K edge are interpreted in terms of a core exciton state lying at or slightly below the conduction-band minimum as determined from x-ray photoelectron data and the optical band gap.

• Research Organization: Naval Research Laboratory, Washington, D.C. 20375
• OSTI ID: 6060988
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 27:4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BERYLLIUM FLUORIDES
CRYSTAL STRUCTURE
ELECTRONIC STRUCTURE
ABSORPTION
ENERGY GAP
EXCITONS
FAR ULTRAVIOLET RADIATION
PHOTOELECTRON SPECTROSCOPY
PRODUCTION MECHANISMS
REFLECTIVITY
REFRACTIVITY
ALKALINE EARTH METAL COMPOUNDS
BERYLLIUM COMPOUNDS
ELECTROMAGNETIC RADIATION
ELECTRON SPECTROSCOPY
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
QUASI PARTICLES
RADIATIONS
SPECTROSCOPY
SURFACE PROPERTIES
ULTRAVIOLET RADIATION
360603* - Materials- Properties