Radial pair distribution function of -quartz at . The curves for the modified fluctuating-charge potential and the original potential lie on top of each other within line thickness. The nearest neighbor peak, which is located at , is not included in the graph.
Phonon density of states in -quartz at . Comparison of BKS, mDCG, TS, and ab initio data (Ref. 37). For clarity the curves for BKS, mDCG, and TS have been shifted upwards.
Temperature dependence of the volume per unit cell at the transition. All of the three different model potentials show qualitative agreement with experiment (Ref. 42). The quantitative agreement is best for the TS potential.
Temperature dependence of the ratio at the transition. For easier comparison the curves are shifted to match at their respective transition temperature. Experimental data from Ref. 42.
Structures of -quartz (top row) and -quartz (bottom row) with dipoles from TS potential. Positions and dipoles are shown in a snapshot (left column) and in an averaged configuration (right column). Projection along the  direction,  direction is vertical.
Equation of state for -quartz under pressure for mDCG and TS. Experiment and BKS both undergo the transition near (Ref. 47).
Interplanar spacing for the compression of -quartz in experiment and simulation. Experimental data by Kingma et al. (Ref. 49).
Time evolution per unit for the two geometries with three different potentials.
Volume per unit against temperature for the three different potentials with the cubic setup. Crosses denote experimental data (Refs. 54 and 65) in the and the phases.
Volume per unit against temperature for the three different potentials with the ABC setup. Crosses denote experimental data (Refs. 54 and 65) in the and the phases. The dotted lines indicate noncrystalline phases.
Equation of state of stishovite. Solid circles are the data of Ross et al. (Ref. 66), Hemley et al. (Ref. 54), and Andrault et al. (Ref. 65); open squares are the data of Mao et al. (Ref. 67).
ratio in stishovite against pressure. Experimental data as in Fig. 11 (Refs. 54 and 65–67). Note that the and the volume are continuous at the phase transition from tetragonal to orthorhombic stishovite.
Birch coefficients as a function of pressure. Simulation data is compared to the result of a Landau expansion by Carpenter et al. (Ref. 61).
Lattice constants and against pressure. Experimental data as in Fig. 11.
Elastic constants of -quartz at in GPa. Experimental data (Expt.) from Ref. 42, taken from Fig. 9.
Bonding angles on the silicon atoms, experiment (Ref. 45) vs model potentials.
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