THE TEMPERATURE-INDUCED STRUCTURAL CHANGE IN AMORPHOUS TiO2
Abstract
Molecular dynamic simulation has been conducted to study the temperature-induced structural change in amorphous titanium dioxide. The simulation model consisting of 1200 atoms is prepared at zero pressure and temperature in the range from 315 to 900K. The local microstructure of considered models is analyzed through the partial radial distribution functions, coordination number, bond-angle and void statistics. The simulation reveals a significant change in void and void aggregation at different temperature, but the angle distribution for basic units TiOx is lightly sensitive to temperature variation; here x=4, 5 and 6. The number of O-voids and Ti-voids strongly depends on temperature. We assume a structural model of amorphous titanium dioxide which constitutes a network of undeformed and identical TiOx units. The heating or cooling leads only to change in the density and corresponding number of basic units.