Experimental Study of the Phase Transition in (CH2)8(NH3)2FeCl4-xBrx(x = 0, 1 and 2)

Abstract

The dielectric constant E and the pyroelectric current I p for the compounds (CH2)S(NH3hFeCI4_xBrx (x = 0, 1 and 2) have been measured in the range from the liquid nitrogen temperature up to near the melting points. Measurements of the dielectric constant have been carried out at various frequencies. A calculation of the electric dipole moments at the background and transition points is given. Calorimetric measurements have also been carried out and the values of the enthalpy change I::.H and entropy change I::.S are also reported.