Synthesis and High-Temperature Heat Capacity of Neodymium Titanate=СИНТЕЗ И ИССЛЕДОВАНИЕ ВЫСОКОТЕМПЕРАТУРНОЙ ТЕПЛОЕМКОСТИ ТИТАНАТА НЕОДИМА

Abstract

Neodymium dititanate, Nd(2)Ti2O(7) (monoclinic structure, sp. gr. P2(1)), has been prepared by solid-state reaction in air at temperatures from 1673 to 1773 K using the Nd2O3 and TiO2 oxides as starting materials. The high-temperature heat capacity of the resultant polycrystalline Nd2Ti2O7 samples has been determined by differential scanning calorimetry. The experimental C (p) (T) data have been used to evaluate the thermodynamic functions of neodymium dititanate (enthalpy increment HA degrees(T)-HA degrees(320 K), entropy change SA degrees(T)-SA degrees(320 K), and reduced Gibbs energy DA degrees(T)) in the temperature range 320-1053 K.