RELATION BETWEEN X-RAY COLORATION AND OPTICAL BLEACHING OF KCI CRYSTALS

Journal Article · Thu Sep 15 04:00:00 EDT 1960 · Physical Review (U.S.) Superseded in part by Phys.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.119.1853· OSTI ID:4140759

Bron, W E

Changes in the absorption of KCI crystals in the spectral region of 200 m mu to 1000 m mu were observed during room temperature x-ray irradiation and subsequent bleaching with F light. It was observed that both coloration and bleaching of the F band occurred in two stages. Secondary centers such as M, R, and V/sub 3/ centers grew primarily during the second stage of coloration, and the rate of growth of these centers during the second stage was enhanced by plastic deformation in a manner similar to that of the F band. It was found that the absorption change at the F band during the first stage of bleaching approximately equaled that during the first stage of coloration. Furthermore, the initial rate of bleaching of the F band was proportional to the initial F band absorption in samples irradiated only into the first stage of coloration but was essentially independent of the initial F band absorption in samples irradiated into the second stage of coloration. It was concluded from this and other evidence that the center responsible for the first stages of coloration and bleaching differed from the center responsible for the second stages of coloration and bleaching. A major point of difference was that the first stage centers were considered to be located in the bulk of the crystal, whereas the second stage centers were located in the vicinity of dislocations. It was also observed that M centers which were formed from F centers during the first stage of bleaching could be bleached with F light. To explain the observations concerning this M band bleaching, it was proposed that M as well as F centers were bleached when they were joined by mobile defects, possibly vacancy pairs. Some of the second stage centers located in the vicinity of dislocations were thought to compete with the centers located in the bulk of the crystal for the mobile defects. (auth)

• Research Organization: International Business Machines Research Center, Yorktown Heights, N.Y.
• NSA Number: NSA-14-024640
• OSTI ID: 4140759
• Journal Information: Physical Review (U.S.) Superseded in part by Phys.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: 119; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
BLEACHING
COLOR
CONFIGURATION
CRYSTALS
DEFECTS
DEFORMATION
DISLOCATIONS
DISTRIBUTION
F CENTERS
LATTICES
LIGHT
M CENTERS
MECHANICS
METALS, CERAMICS, AND OTHER MATERIALS
POTASSIUM CHLORIDES
RADIATION EFFECTS
SPECTRA
STABILITY
V CENTERS
VACANCIES
X RADIATION