Structure of Liquid Aluminum Oxide

Molecular-dynamics simulations of liquid aluminum oxide

“…Energy fluctuations were of 0.01 kJ/mol around the mean value although there was a temperature drift in the equilibration runs of plus or minus 40 K. Figure 1 shows the total radial distribution functions of the simulated system at 2260 and 2990 K. Figure 2 shows the structure factor S(q) for the system at 2260 K obtained by Fourier transforming the corresponding g(r). For the sake of comparison, the experimental results reported by Ansell et al 1 have also been included in these figures. The two curves corresponding to liquid alumina in Fig.…”

“…3 Recently a report of the experimental determination of the structure of liquid aluminum oxide has been published. 1 In order to complement this experiment, in this work we report the results of molecular-dynamics ͑MD͒ simulations of liquid aluminum oxide, and discuss a model to describe its structure.…”

Absorption Coefficient of Molten Aluminum Oxide in Semitransparent Spectral Range

“…Droplets of 3-4 mm in diameter were suspended also by aerodynamic levitation in different gases (air, oxygen, nitrogen) and were heated by CO 2 laser radiation. The temperature range in the studies was 2200-2700 K. The results in (Ansell et al, 1997) show that the melting of -Al 2 O 3 affects radically the structure and coordination. In the melt, the Al-O coordination number is 4.4, i.e., (AlO 4 ) 5-tetrahedrons (the basis of the melt structure) contact with other tetrahedrons, and so the structure is like -Al 2 O 3 .…”

“…These are experimental studies (Waseda, Sugiyama, & Toguri, 1995;Ansell, Krishnan, Weber, Felten, & Nordine, 1997;Landron, Hennet, & Thiaudiere, 2001;Krishnan et al, 2005) and molecular dynamics simulations (San Miguel, Sanz, Fernandes, Alvares, & Ordiozola, 1998;Gutierres, Belonoshko, Ahuja, & Johansson, 2000;Ahuja et al, 2004;Vashishta, Kalia, Nakano, & Rino, 2008). Although there are some disagreements between various studies, in most of them, except (Waseda et al, 1995), the conclusion is made that the short-range order in molten alumina is essentially defined by a (AlO 4 ) 5-basic unit, i. e., liquid Al 2 O 3 shows -phase-like coordination.…”

“…The subject of investigation in reference (Ansell et al, 1997) was the structure of molten Al 2 O 3 in normal and supercooled state. The experiments were carried out using diffraction of X-ray synchrotron radiation.…”