X-RAY STUDY OF INTERSTITIAL DEFECTS IN RADIATION-DAMAGED ALKALI HALIDES AND LiH

Journal Article · Wed Aug 01 04:00:00 EDT 1962 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.127.777· OSTI ID:4776510

Pretzel, F E; Petty, R L

The effects of exposure to tritium BETA particles at 77 deg K on the lattice parameters of Si, LiH, LiF, NaCl, KCl, and KBr were examined by x-ray diffraction studies by employing a sample stage cooled by liquid nitrogen. The Si and LiH lattice parameters remained constant during BETA irradiation from an external source, but all of the alkali halides showed large increases in lattice parameter. Maximum unit cell volume expansions observed were 0.2% in LiF, 0.6% in NaCl and KCl, and 0.3% in KBr. Measurements of unit cell expansion and bulk crystal expansion of LiH crystals containing LiT were also continued to determine more accurately the expansion per interstitial He/sup 3/ atom. The results are interpreted on the basis of the formation of Frenkel pairs (interstitial anion plus anion vacancy) in the alkali halides by a moderately efficient process. The process involves the transport of interstitial defects through 50 mu into materials for which the BETA range is about 2 mu . It is proposed that this may occur either directly, by an interstitialcy mechanism, or indirectly, by exciton interactions within the crystals. Comparisons between the results of low- temperature studies of lattice expansion and color centers in alkali halides are made, and possible interrelations between the various defects formed by radiation damage are proposed. (auth)

• Research Organization: Los Alamos Scientific Lab., N. Mex.
• NSA Number: NSA-16-029459
• OSTI ID: 4776510
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 127; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BETA DECAY
COLOR
CONFIGURATION
CRYSTALS
DEFECTS
DIFFRACTION
DIFFUSION
DIFFUSION LENGTH
ELECTRON BEAMS
EXCITATION
EXCITONS
EXPANSION
FRENKEL PAIRS
HELIUM 3
INTERACTIONS
INTERSTITIALS
IRRADIATION
LATTICES
LITHIUM FLUORIDES
LITHIUM HYDRIDES
LOW TEMPERATURE
METALS, CERAMICS, AND OTHER MATERIALS
POTASSIUM BROMIDES
POTASSIUM CHLORIDES
RADIATION EFFECTS
SILICON
SODIUM CHLORIDES
TRITIUM
X RADIATION