# Data sets for the Journal of Non-Crystalline Solids X: Article entitled "Pressure induced structural transformations in amorphous MgSiO_3 and CaSiO_3"

Dataset

### Description

Data sets used to prepare Figures 1-14 in the Journal of Non-Crystalline Solids X article entitled "Pressure induced structural transformations in amorphous MgSiO_3 and CaSiO_3." The files are labelled according to the figure numbers. The data sets were created using the methodology described in the manuscript. Each of the plots was drawn using QtGrace (https://sourceforge.net/projects/qtgrace/). The data set corresponding to a plotted curve within an QtGrace file can be identified by clicking on that curve. The units for each axis are identified on the plots.

Figure 1 shows the pressure-volume EOS at room temperature for amorphous and crystalline (a) MgSiO_3 and (b) CaSiO_3.

Figure 2 shows the pressure dependence of the neutron total structure factor S_{\rm N}(k) for amorphous (a) MgSiO_3 and (b) CaSiO_3.

Figure 3 shows the pressure dependence of the neutron total pair-distribution function $G_{\rm N}(r) for amorphous (a) MgSiO_3 and (b) CaSiO_3. Figure 4 shows the pressure dependence of several D_{\rm N}^\prime(r) functions for amorphous MgSiO_3 measured using the D4c diffractometer. Figure 5 shows the pressure dependence of the Si-O coordination number in amorphous (a) MgSiO_3 and (b) CaSiO_3, the Si-O bond length in amorphous (c) MgSiO_3 and (d) CaSiO_3, and (e) the fraction of n-fold (n = 4, 5, or 6) coordinated Si atoms in these materials. Figure 6 shows the pressure dependence of the M-O (a) coordination number and (b) bond length for amorphous MgSiO_3 and CaSiO_3. Figure 7 shows the S_{\rm N}(k) or S_{\rm X}(k) functions for (a) MgSiO_3 and (b) CaSiO_3 after recovery from a pressure of 8.2 or 17.5 GPa. Figure 8 shows the G_{\rm N}(r) or$G_{\rm X}(r) functions for (a) MgSiO_3 and (b) CaSiO_3 after recovery from a pressure of 8.2 or 17.5 GPa.

Figure 9 shows the pressure dependence of the Q^n speciation for fourfold coordinated Si atoms in amorphous (a) MgSiO_3 and (b) CaSiO_3.

Figure 10 shows the pressure dependence in amorphous MgSiO_3 and CaSiO_3 of (a) the overall M-O coordination number and its contributions from M-BO and M-NBO connections, (b) the fractions of M-BO and M-NBO bonds, and (c) the associated M-BO and M-NBO bond distances.

Figure 11 shows the pressure dependence of the fraction of n-fold (n = 4, 5, 6, 7, 8, or 9) coordinated M atoms in amorphous (a) MgSiO_3 and (b) CaSiO_3.

Figure 12 shows the pressure dependence of the O-Si-O, Si-O-Si, Si-O-M, O-M-O and M-O-M bond angle distributions (M = Mg or Ca) for amorphous MgSiO_3 (left hand column) and CaSiO_3 (right hand column).

Figure 13 shows the pressure dependence of the q-parameter distributions for n-fold (n = 4, 5, or 6) coordinated Si atoms in amorphous (a) MgSiO_3 and (b) CaSiO_3.

Figure 14 shows the pressure dependence of the q-parameter distributions for the M atoms in amorphous MgSiO_3 (left hand column) and CaSiO_3 (right hand column).
Date made available 10 May 2019 University of Bath

### Cite this

Salmon, P. (Creator), Zeidler, A. (Creator) (10 May 2019). Data sets for the Journal of Non-Crystalline Solids X: Article entitled "Pressure induced structural transformations in amorphous MgSiO_3 and CaSiO_3". University of Bath. 10.15125/BATH-00601