phase transition

Calculation of transverse piezoelectric characteristics of quasi-one-dimensional glycine phosphite ferroelectric

The model of the glycine phosphite crystal, modified by taking into account of piezoelectric coupling of ordering structure elements with the lattice strains, is used for investigation of piezoelectric characteristics of the crystal. In the frames of two-particle cluster approximation the transverse  piezoelectric coefficients  are calculated. The influences of hydrostatic, uniaxial pressures, shear stresses and transverse electric fields on the transverse  piezoelectric coefficients of the crystal are studied.

Calculation Method of Heat Capacity Change during Organic Compounds Vaporization and Sublimation

On the basis of literature data the constancy of heat capacity change during vaporization ( 2 %) and sublimation ( 8 %) has been determined at 298 K for different organic compounds. The obtained equations allow to recalculate the enthalpy according to Kirchhoff’s law easier compared with present techniques based on the increments method. The vaporization and sublimation enthalpies of 5-(2-nitrophenyl)-furan-2-carbaldehyde have been determined and recalculated for 298 K for the reliability proofing of the suggested method.