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2.5 Complex structures

Oxides: Silicates- overview 1

From simple building units to complex structures

Structural features:
Structural features:
• fundamental building unit: SiO tetrahedron
4
• isolated tetrahedra or connection via common corners

• MO octahedra , MO tetrahedra (M = Fe, Al, Co, Ni…)
6
4

Nesosilicates Sorosilicates Cyclosilicates
Sorosilicates
Nesosilicates
Cyclosilicates
SiO 4 4- Si O 7 6- SiO 3 2-
2
Olivine: (Mg,Fe) SiO 4 Thortveitite: (Sc,Y) Si O 7 Beryl: Be Si O 18
3
6
2
2
2