TY  - SER
AU  - ANDRIYEVSKYY, Bohdan.
TI  - Simultaneous pyroelectric and dilatometric studies of phase transitions in triglycine sulphate and glycine phosphite crystals
PY  - 2001///
N1  - Dane z Informatora o publikowanych wynikach prac naukowo-badawczych w 2001 roku Wydziału Elektroniki
N2  - Temperature dependences of the linear dimension L(T) and spontaneous polarization Ps~((T) for triglycine sulphate and glycine phosphite single crystals have been measured in the same run of temperature. A decrease in the spontaneous electrostriction coefficient QL~( of both crystals studied is displayed when approaching the corresponding phase transition point T c~(. A temperature dependence of the coefficients QL~((T) shows that the rates of temperature changes of displacement of the atomic complexes of corresponding crystal structure forming the square of spontaneous polarization Ps~(2~) (promary order parameter) and the displacements of all atomic complexesforming the spontaneous linear thermal expansion δLs~(/L (secondary order parameter) are different. The applying external electric field E=3x105~) V/m to triglycine sulphate crystal does not influence essentially the temperature dependence of QL~((T) in the temperature range of phase transition below Tc~(
ER  -