Geoscience Reference
In-Depth Information
Compound
Representative
Cell Parameter (
˚
)
Rare Earth, Co.
No., Average
Bond Distance (
˚
)
Tetrahedral Radical Form
Rare Earth Polyhedra
R
2
[SiO
4
]O
Gd
2
[SiO
4
]O
P2
1
/cz
5
4
Gd
1
7
2.39
Orthotetrahedra
Framework
R
5
La
Tb
a
5
9.12
Gd
2
9
2.49
b
5
7.06
c
5
6.73
β
5
107.58
R
2
[SiO
4
]O
Yb
2
[SiO
4
]O
B2/bz
5
8
Yb
1
7
2.33
Orthotetrahedra
Framework
R
5
Tb
Lu, Y
a
5
14.28
b
5
10.28
Yb
2
6
2.33
c
5
6.653
γ
5
122.2
R
4
.
67
[SiO
4
]
3
O d
4.67
[SiO
4
]
3
O
P6
3
/mz
5
2
Gd
1
7
2.41
Orthotetrahedra
Framework
R
5
La
Lu
a
5
9.431
Gd
2
9
2.53
b
5
9.873
α
-Eu
2
1
2
[SiO
4
]
P2
1
/cz
5
4
Eu
1
8
2.62
Orthotetrahedra
Framework
a
5
5.661
b
5
7.101
Eu
2
10
2.86
c
5
11.518
β
5
122.01
β
-Eu
2
1
2
[SiO
4
]
Pnma z
5
4
Eu
1
10
2.86
Orthotetrahedra
Framework
a
5
7.137
b
5
5.665
Eu
2
7
2.57
c
5
9.767
R
2
Si
2
O
7
Sm
2
Si
2
O
7
P4
1
z
5
8
Sm
1
7
2.42
Diortho-
Framework
R
5
La
Eu
a
5
6.695
Sm
2
9
2.56
(Continued)