Electrical conduction in ferroelectric lead hydrogen phosphate single crystals

Abstract

Single crystals of LHP (Lead Hydrogen Phosphate) have been grown using the controlled reaction between lead nitrate and orthophosphoric acid solution by diffusion process in silica gel medium. Transparent crystals upto 6 x 4 X 3 mm3 in size have been grown at room temperature. The d.c. electrical conductivity of both single crystals and pelletized saiiiples of LHP have been studied in the temperature range from 313 to 968 K. It has been observed that: (i) the d.c. conductivity of the crystalline sample is greater than that of thepellet sample, (ii) three distinct electrical conductivity processes have been observed arid are interpreted as extrinsic, intrinsic, phase changes, and (iii) the activation euergy for the conduction in the crystalline sample is greater than that of the pellet sample. Thc magnetic susceptibility measurements reveal that the paramagnetic characteristic of these materials and the implications are discussed.

Electrolytic growth and properties of single crystals of ammonium hydrogen tartrate

“…The crystallization apparatus used is an electrolytic cell (length 20 cm, diameter 2-5 cm) as shown in figure 1. The procedure for preparation of gels has been reported earlier (Desai and Ramana 1987). The gel was transferred to the electrolyte cell, allowed to set and 1-50 M NH4C1 (feed) solution was poured.…”

Synthesis, characterization and properties of ferroelectric rubidium hydrogen tartrate single crystals

“…Gel media offers an efficient and simple technique for their growth. Recently a variety of crystals such as KDP or ADP (Lefaucheux et al 1982), PbHPO 4 (Desai and Ramana 1987), NaC1, KCI (Desai and Rai 1980) and also metallic crystals like Ag and Cu (Blank 1971) have been grown using gel medium.…”