Surface Charging of Triglycine Sulfate

Abstract

Virgin crystals of triglycine sulfate were found to emit light when heated through the ferroelectric Curie temperature. This light comes from electrical discharges into the surrounding atmosphere, and both the first negative and the second positive band spectra of nitrogen have been observed. The crystal will repeat the phenomenon only if it is exposed to a humid environment. The moisture layer responsible for the sparking phenomenon does not exceed 50 Å in thickness.