The structural transition under compression and correlation between structural and dynamical heterogeneity for liquid Al₂O₃

Abstract

This study reported a simulation of structural transition and correlation between structural and dynamical heterogeneity (DH) for liquid Al2O3. Structural characteristics of liquid Al2O3 were clarified through the pair radial distribution functions, the distribution of [Formula: see text] and [Formula: see text] ([Formula: see text], 4, 5, 6; [Formula: see text], 2, 3) basic structural units, angle and bond length distribution and 3D visualization. Simulation results revealed that network structure of liquid Al2O3 is built mainly by AlO3, AlO4, AlO5 and AlO6 units that are linked to each other through common oxygen atoms. We found the existence of separate AlO4-, AlO5- and AlO6-phases where the mobility of atoms can be determined. The atoms in AlO4-phase are more mobile than the ones in AlO5- and AlO6-phases. The existence of separate phases is evidence of DH in liquid Al2O3. Moreover, the self-diffusion of Al and O atoms was also discussed via characteristics of separate AlO4-, AlO5- and AlO6-phases.

Characterization of Structural Transition and Heterogeneity under Compression for Liquid Al2O3 Using Molecular Dynamics Simulation

“…These averaged coordination number of Al-O pair is approximately estimated to be 4.3 ± 0.05. To support experimental methods, simulation is also a powerful method to investigate the microstructure of melts, especially at high-temperature and/or pressure conditions [13][14][15][16][17][18][19]. According to the first-principles molecular dynamic (MD) simulations, Verma et al [8] determined that the liquid Al2O3 is more sensitive to the applied compression than the temperature.…”

The Structural Characteristics and Phase Transformation in Al2O3 Glass. A Molecular Dynamics Simulation

“…Therefore, in this work, we focus on studying the structural characteristics and indicating the existence of two phases with high-and low-density of Al2O3 glass. The properties of Al2O3 can be inferred from simulated models by the bond length, bond-angle, coordination number, and cluster function [13,14].…”

Interfacial engineering of mp-TiO2/CH3NH3PbI3 with Al2O3: Effect of different phases of alumina on performance and stability of perovskite solar cells

“…The structure of α-Al 2 O 3 can be regarded as an hcp sublattice of oxygen anions so that aluminum cations in an ordered array filled the octahedral interstices. In the hexagonal description, the oxygen anions in α-Al 2 O 3 distribute 18c Wyckoff sites, whereas the aluminum cations are occupied at 12c sites [25].…”