Electron microscopy
 
P2/c (13) Space Group
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Table 1668. P2/c (13) space group.

Name in the International Tables for Crystallography
P2/c P
10 2/m
Crystal system
Monoclinic 2/m
Asymm
0 ≤ x ≤ 1/2 and 0 ≤ y ≤ 1 and 0 ≤ z ≤ 1/2
4 Absence of reflections

00l (l = 2n), e.g. on [100] zone axis

Translation
 
Symmetry (atomic coordinates)
X, Y, Z; -X, Y, 1/2-Z; -X, -Y, -Z; X, -Y, 1/2+Z
Crystal examples
Bi12.8Co0.2Mo5O34±δ: a = 11.7226(6) Å; b = 5.7959(2) Å; c = 24.6994(11)Å; β = 102.08(1)°; Unit cell volume = 1640.92(2) (Å3); formula units (Z) = 2. [1]

Figure 1668 shows a selected area electron diffraction (SAED) pattern of an Bi12.8Co0.2Mo5O34±δ crystal taken along [010] and [100] zone axes. The forbidden reflections still appeared due to double diffraction. However, this effect disappeared when the crystal was tilted away from the perfect zone axis orientation. The weak lines of the diffuse scattering along the c* direction (e.g. marked by the red arrow) indicated the presence of atomic disordering of this crystal structure.

Selected area electron diffraction (SAED) pattern of an Bi12.8Co0.2Mo5O34±δ crystal taken along [100] zone axis
Selected area electron diffraction (SAED) pattern of an Bi12.8Co0.2Mo5O34±δ crystal taken along [100] zone axis
(a)
(b)

Figure 1668. Selected area electron diffraction (SAED) pattern of an Bi12.8Co0.2Mo5O34±δ crystal taken along [010] (a) and [100] (b) zone axes. Adapted from [1]

 

 

 

 

 

[1] Z. A. Mikhailovskaya, E. S. Buyanova, S. A. Petrova, M. V. Morozova, V. M. Zhukovskiy, R.G. Zakharov, N. V. Tarakina, I. F. Berger, Cobalt-doped Bi26Mo10O69: Crystal structure and conductivity, Journal of Solid State Chemistry 204 (2013) 9–15.

 

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