0000000000591304
AUTHOR
Patrick Pfleiderer
showing 3 related works from this author
Structure and transport properties of amorphous aluminium silicates: computer simulation studies
2005
The structure and transport properties of SiO2-Al2O3 melts containing 13 mol% and 47 mol% Al2O3 are investigated by means of large scale molecular dynamics computer simulations. The interactions between the atoms are modelled by a pair potential which is a modified version of the one proposed by Kramer et al. [J. Am. Chem. Soc. 64, 6435 (1991)]. Fully equilibrated melts in the temperature range 6000 K >= T > 2000 K are considered as well as glass configurations, that were obtained by a rapid quench from the lowest melt temperatures. Each system is simulated at two different densities in order to study the effect of pressure on structural and dynamic properties. We find that the Al ato…
Simple monoclinic crystal phase in suspensions of hard ellipsoids
2006
We present a computer simulation study on the crystalline phases of hard ellipsoids of revolution. For aspect ratios $\ensuremath{\geqslant}3$ the previously suggested stretched-fcc phase [Frenkel and Mulder, Mol. Phys. 55, 1171 (1985)] is replaced by a different crystalline phase. Its unit cell contains two ellipsoids with unequal orientations. The lattice is simple monoclinic. The angle of inclination of the lattice, $\ensuremath{\beta}$, is a very soft degree of freedom, while the two right angles are stiff. For one particular value of $\ensuremath{\beta}$, the close-packed version of this crystal is a specimen of the family of superdense packings recently reported [Donev et al., Phys. R…
Glassy dynamics in monodisperse hard ellipsoids
2008
We present evidence from computer simulations for glassy dynamics in suspensions of monodisperse hard ellipsoids. In equilibrium, almost spherical ellipsoids show a first order transition from an isotropic phase to a rotator phase. When overcompressing the isotropic phase into the rotator regime, we observe super-Arrhenius slowing down of diffusion and relaxation, accompanied by two-step relaxation in positional and orientational correlators. The effects are strong enough for asymptotic laws of mode-coupling theory to apply. Glassy dynamics are unusual in monodisperse systems. Typically, polydispersity in size or a mixture of particle species is prerequisite to prevent crystallization. Here…