Constituent
Name
Glassy silicate (1-x)MgO-xSiO2 x=0.40
Official name
Mg2SiO4-MgSiO3 series
Family
covalent network solid
Class
tridimentional covalent network solid
Compound type
non-oxide ceramic
Constituent abundance in material
Relevance
main - major
Arrangement
single phase
Mass fraction
1.0
Mole fraction
1.0
Chemical composition
Formula
$(1-x)MgO-xSiO_2 x=0.40$. $(MgO)_{1.5}.SiO_2$
Chemical formula
(MgO)2(SiO2)x
Elemental formula
(Mg)1.5-2 (Si)1-2 (O)3.5-6
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Mole fraction Isotope mole fraction State Relevance
$Mg$ Magnesium element 1.5 - 2 0.21875 $\pm$ 0.03125 1.0 pure main
$Si$ Silicon element 1 - 2 0.1875 $\pm$ 0.0625 1.0 pure main
$O$ Oxygen element 3.5 - 6 0.59375 $\pm$ 0.15625 1.0 pure main
Class
molecular solids with apolar molecules (01)
Type
with monoatomic apolar molecules (A) (01.01)
Phase type
glassy
Crystal system
amorphous
Crystal class
N/A
Crystal class symbol
N/A
Crystal spacegroup
N/A
Molar mass
140.69 - 200.78 $g/mol$
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