Solid phase
Official name
Mg2SiO4-MgSiO3 series
Type
Family
covalent network solid
Class
tridimentional covalent network solid
Compound type
non-oxide ceramic
Chemical composition
Formula
$(MgO)_2.(SiO2)_x$ - x=1-2
Chemical formula
(MgO)2(SiO2)x
Elemental formula
Mg2 (Si)1-2 (O)4-6
Isotope mixture type
terrestrial abundance
17.0
  Formula Name Family Number min-max Mole fraction Isotope mole fraction State Relevance
$Mg$ Magnesium element 2 0.23529411764705882 1.0 pure main
$Si$ Silicon element 1 - 2 0.17647058823529413 $\pm$ 0.058823529411764705 1.0 pure main
$O$ Oxygen element 4 - 6 0.5882352941176471 $\pm$ 0.11764705882352941 1.0 pure main
Class
molecular solids with apolar molecules (01)
Type
with monoatomic apolar molecules (A) (01.01)
Phase type
crystalline
Crystal system
orthorhombic
Crystal class
dipyramidal
Crystal class symbol
mmm (D2h)
Molar mass
140.69 - 200.78 $g/mol$
State NTP
solid
Refringence type
biaxial
Refringence sign
positive or negative
Birefringence
0.009 - 0.033
Refraction index $n_{\alpha}$
1.636 - 1.668
Refraction index $n_{\beta}$
1.650 - 1.673
Refraction index $n_{\gamma}$
1.659 - 1.679