Accession Number : ADD005187

Title :   Photodichroic Crystals and Preparation Thereof.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON D C

Personal Author(s) : Schneider,Irwin ; Collins,William C ; Imber,Oscar ; Klein,Philipp H

Report Date : 02 May 1978

Pagination or Media Count : 8

Abstract : Patent on the improvement of the electrolytic and additive methods of coloring alkali fluoride crystals comprising the step of selecting an alkali fluoride crystal having the impurities of between 0 and 5 ppmA of OH; between 0 and 50 ppmA of one or more alkaline earth cations, of which between 0 and 10 ppmA Mg++ and between 0 and 10 ppmA Ca++; between 0 and 50 ppmA of nonfluorine halide anions; between 0 and 10 ppmA of SiF6=, between 0 and 30 ppmA of other ions; and the method of preparing these crystals which comprises converting the alkali fluoride to alkali hydrofluoride, crystallizing and vacuum drying the alkali hydrofluoride crystals, regenerating the alkali fluoride by expelling hydrogen fluoride, and crystallizing the alkali fluoride. (Author)

Descriptors :   *Patents, *Crystals, Color centers, Electrolytes, Crystal growth

Subject Categories : Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE