Ferroelectricity in glycine picrate: An astonishing observation in a centrosymmetric crystal

Remarkable ferroelectric property has been observed in the glycine picrate single crystal though it crystallizes in centrosymmetric structure. An anomaly at 105 degrees C was observed in dielectric and ac conductivity measurements. The activation energies for conduction (E-a) below and above this temperature are found to be 0.31 and 0.53 eV, respectively. The remanant polarization (P-r) and coercive field (E-c) at room temperature were found to be 0.64 mu C/cm(2) and 6.22 kV/cm, respectively. However, a remarkable increase in these values was observed above 105 degrees C. A significantly high d(33) (piezoelectric charge coefficient) in the order of 18 pC/N was observed. (C) 2009 American Institute of Physics. [doi:10.1063/1.3275714]