Structural and Dielectric Properties of Organic Ferroelectric 2-Methylbenzimidazole

Resumo

2-methylbenzimidazole single crystals and films are obtained by evaporation from an ethanol solution. The films have a texture with a predominant orientation of the pseudotetragonal axis in the film plane. The blocks are split crystals of the spherulite type, in which the pseudotetragonal axis rotates around the block center. Dielectric hysteresis loops are investigated in the crystals and films in the temperature range of 290–350 K. In the films, loops are observed for both in-plane and out-of-plane electric-field orientation. The maximum value of polarization in the films is close to that observed in single crystals P_s ~ 5 μC/cm². The difference in the temperature behavior of the hysteresis loops in the crystals and films is associated with the specific structure of the blocks.