Figure 5.8. Electronic charge deformation map (crystal - isolated atoms) for stishovite. Atomic positions as in figure 5.6 and intervals as in Figure 5.7. Full and dashed lines indicate positive and negative values respectively; dot-dashed line corresponds to the zero-level.
Figure 5.9. Electronic charge difference map corresponding to quartz described by a basis set with and without d orbitals respectively (6-21G**- 6-2 lg ). Atomic positions as in figure 5.5 and intervals as in Figure 5.7. Full and dashed lines correspond to positive and negative values respectively; dot-dashed line corresponds to the zero-level.
I__I
Figure 5.10. Electronic charge difference map corresponding to stishovite described by a basis set with and wihout d orbitals respectively (6-21G**- 6-2lg). Atomic positions as in figure 5.6 and intervals as in Figure 5.7. Full and dashed lines correspond to positive and negative values respectively; dot-dashed line corresponds to the zero-level.
Figure 5.11 A perspective view o f the ilmenite structured MgSiC^ after Horiuchi et al. (1982). Open circles, oxygen; shaded circles, Mg; black circles, Si.
300
O 2s
3000 2p
30Si 3s
Aa
30Si 3p
30 -2 5ENERGY (eV)
Figure 5.12 Total and projected density o f states o f M gSi0 3 The vertical
scale in the case o f Si states is expanded by a factor o f ten.
Figure 5.13 Electron charge deformation map (crystal - isoalted atoms) corresponding to a plane cutting the O-Si-O plane. Full and dashed lines indicate positive and negative values respectively; dot-dashed line corresponds to the zero-level.Contour intervals correspond to increases o f 0.010 el/(a.u.)3
I / I ' l l /
lift:
' 111' •1 ■‘f t\ m
I \ 'V ' . W V N
Figure 5.14 Electron charge deformation map (crystal - isoalted atoms) corresponding to a plane cutting the O-Mg-O plane. Full and dashed lines indicate positive and negative values respectively; dot-dashed line corresponds to the zero-level.Contour intervals correspond to increases o f 0.010 el/(a.u.)3
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