-    DIAMOND (9R)     -    C

 

Crystal Structure 


Because of the translational symmetry all the calculations are performed in the primitive unit cell and not in the conventional unit cell. The following information regarding the structure is given with respect to this primitive unit cell, which sometimes can take an unintuitive shape.

Symmetry (experimental): 

Space group:  156  P3m1 
Lattice parameters (Å):  1  1  1 
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  156  P3m1 
Lattice parameters (Å):  2.4783  2.4783  18.4586 
Angles (°):  90  90  120 

Cell contents: 

Number of atoms:  12 
Number of atom types:  1 
Chemical composition:  0 

Atomic positions (theoretical):

C:  0.0000  0.0000  0.9981 
C:  0.0000  0.0000  0.0818 
C:  0.6667  0.3333  0.1098 
C:  0.6667  0.3333  0.1934 
C:  0.0000  0.0000  0.2215 
C:  0.0000  0.0000  0.3051 
C:  0.6667  0.3333  0.3331 
C:  0.6667  0.3333  0.4168 
C:  0.0000  0.0000  0.4446 
C:  0.0000  0.0000  0.5269 
C:  0.3333  0.6667  0.5547 
C:  0.3333  0.6667  0.6384 
Atom type  X  Y  Z 

We have listed here the reduced coordinates of all the atoms in the primitive unit cell.
It is enough to know only the position of the atoms from the assymetrical unit cell and then use the symmetry to build the whole crystal structure.

Visualization of the crystal structure: 

Size:

 Nx:  Ny:  Nz: 
You can define the size of the supercell to be displayed in the jmol panel as integer translations along the three crys­tallo­gra­phic axis.
Please note that the structure is represented using the pri­mi­tive cell, and not the conventional one.
     

Powder Raman 

Powder Raman spectrum

The intensity of the Raman peaks is computed within the density-functional perturbation theory. The intensity depends on the temperature (for now fixed at 300K), frequency of the input laser (for now fixed at 21834 cm-1, frequency of the phonon mode and the Raman tensor. The Raman tensor represents the derivative of the dielectric tensor during the atomic displacement that corresponds to the phonon vibration. The Raman tensor is related to the polarizability of a specific phonon mode.

Choose the polarization of the lasers.

I ∥ 
I ⊥ 
I Total 
Horizontal:
Xmin:
Xmax:
Vertical:
Ymin:
Ymax:
 

Data about the phonon modes

Frequency of the transverse (TO) and longitudinal (LO) phonon modes in the zone-center. The longitudinal modes are computed along the three cartesian directions. You can visualize the atomic displacement pattern corresponding to each phonon by clicking on the appropriate cell in the table below.

1
ac
0
0
0
0
2
ac
0
0
0
0
3
ac
0
0
0
0
4
E
201
201
201
201
6.479e+37
0.1
8.908e+37
0.2
1.539e+38
0.3
5
E
201
201
201
201
6.479e+37
0.1
8.908e+37
0.2
1.539e+38
0.3
6
E
205
205
205
205
6.501e+37
0.1
8.939e+37
0.2
1.544e+38
0.3
7
E
205
205
205
205
6.501e+37
0.1
8.939e+37
0.2
1.544e+38
0.3
8
A1
339
339
339
339
2.574e+38
0.5
1.331e+37
0.0
2.707e+38
0.5
9
A1
343
343
343
343
2.134e+38
0.4
1.284e+37
0.0
2.262e+38
0.4
10
E
369
369
369
369
1.372e+38
0.2
1.781e+38
0.3
3.154e+38
0.6
11
E
369
369
369
369
1.366e+38
0.2
1.868e+38
0.3
3.234e+38
0.6
12
E
371
371
371
371
1.793e+38
0.3
2.332e+38
0.4
4.125e+38
0.7
13
E
371
371
371
371
1.789e+38
0.3
2.446e+38
0.4
4.234e+38
0.8
14
E
478
478
478
478
5.018e+37
0.1
5.686e+37
0.1
1.070e+38
0.2
15
E
478
478
478
478
4.868e+37
0.1
6.201e+37
0.1
1.107e+38
0.2
16
E
485
485
485
485
7.078e+37
0.1
8.346e+37
0.1
1.542e+38
0.3
17
E
485
485
485
485
6.950e+37
0.1
9.139e+37
0.2
1.609e+38
0.3
18
E
533
533
533
533
1.424e+37
0.0
1.653e+37
0.0
3.077e+37
0.1
19
E
533
533
533
533
1.388e+37
0.0
1.807e+37
0.0
3.195e+37
0.1
20
E
540
540
540
540
1.892e+36
0.0
2.011e+36
0.0
3.904e+36
0.0
21
E
540
540
540
540
1.748e+36
0.0
1.918e+36
0.0
3.666e+36
0.0
22
A1
649
649
649
649
1.055e+39
1.9
6.647e+37
0.1
1.121e+39
2.0
23
A1
650
650
650
650
1.022e+39
1.8
5.252e+37
0.1
1.074e+39
1.9
24
A1
894
894
894
894
1.587e+39
2.8
1.785e+38
0.3
1.765e+39
3.1
25
A1
898
898
898
898
1.448e+39
2.6
1.512e+38
0.3
1.599e+39
2.8
26
A1
1052
1052
1052
1052
5.439e+38
1.0
9.759e+37
0.2
6.414e+38
1.1
27
A1
1053
1053
1053
1053
2.644e+38
0.5
4.962e+37
0.1
3.140e+38
0.6
28
E
1222
1222
1222
1222
2.322e+40
41.4
3.290e+40
58.6
5.613e+40
100.0
29
E
1222
1222
1222
1222
2.302e+40
41.0
1.733e+40
30.9
4.035e+40
71.9
30
E
1231
1231
1231
1231
1.727e+40
30.8
2.507e+40
44.7
4.234e+40
75.4
31
E
1231
1231
1231
1231
1.712e+40
30.5
1.301e+40
23.2
3.013e+40
53.7
32
E
1245
1245
1245
1245
5.153e+39
9.2
7.608e+39
13.6
1.276e+40
22.7
33
E
1245
1245
1245
1245
5.103e+39
9.1
3.915e+39
7.0
9.018e+39
16.1
34
E
1258
1258
1258
1258
1.388e+39
2.5
2.090e+39
3.7
3.478e+39
6.2
35
E
1258
1258
1258
1258
1.375e+39
2.5
1.071e+39
1.9
2.446e+39
4.4
36
A1
1275
1275
1275
1275
1.035e+39
1.8
4.773e+38
0.9
1.512e+39
2.7
No.  Char.  ω TO  ω LOx  ω LOy  ω LOz  I ∥  I ⊥  I Total 

You can define the size of the supercell for the visualization of the vibration.

Nx: 
Ny: 
Nz: 
Normalized
Raw
Options for intensity.