Mechanoluminescence of halogenate crystals

✍ Scribed by Dr. B. P. Chandra; R. D. Verma

• Publisher: John Wiley and Sons
• Year: 1980
• Tongue: English
• Weight: 471 KB
• Volume: 15
• Category: Article
• ISSN: 0232-1300
• DOI: 10.1002/crat.19800151024

✦ Synopsis

Abstract

Mechanoluminescence (ML) has been studied in twenty halogenate crystals. All piezoelectric crystals show ML similar to the emission from second positive group of molecular nitrogen, and all the crystals not exhibiting ML are non‐piezoelectric. Some of the non‐piezoelectric crystals also exhibit nitrogen emission ML which is comparable in intensity to that of piezoelectric crystals. The ML appears only during the different steps developing in the fracture region of the force versus compression curve of the crystals. No considerable change in the ML activity is found due to the number of crystallization or due to the addition of different impurities from 100 to 10.00 ppm. The ML activity per mole of the halogenate crystals varies around four orders of magnitude. It is concluded that in addition to the piezoelectrification of the newly created surfaces there exists some other process of electrification which may cause the ML exitation in halogenate crystals.