Synthesis, structure, and properties of 4,8,12-trioxa-12c-phospha-4,8,12,12c-tetrahydrodibenzo-(cd,mn)pyrene, a molecular pyroelectric

Phosphangulene or 4,8,12-trioxa-12c-phospha-4,8,12,12c-tetrahydrodibenzo-(cd,mn)pyrene was synthesized and its crystalline structure was determined. The compound has a permanent polarization and consequent pyroelectric characteristics. It was found to belong to a rare space group and to have pyroelectric properties which have been determined in the temperature range 20-110 degrees C. The material can be used for infrared detection and is comparable in performance with known materials but has a significant vapor pressure just above room temperature, making application difficult.