-    DIAMOND (6H)     -    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:  194  P6_3/mmc 
Lattice parameters (Å):       
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  194  P6_3/mmc 
Lattice parameters (Å):  2.4829  2.4829  12.2469 
Angles (°):  90  90  120 

Cell contents: 

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

Atomic positions (theoretical):

C:  1.0000  1.0000  0.9983 
C:  1.0000  1.0000  0.1246 
C:  0.3333  0.6667  0.1664 
C:  0.3333  0.6667  0.2907 
C:  0.6667  0.3333  0.3322 
C:  0.6667  0.3333  0.4565 
C:  1.0000  1.0000  0.4983 
C:  1.0000  1.0000  0.6246 
C:  0.6667  0.3333  0.6664 
C:  0.6667  0.3333  0.7907 
C:  0.3333  0.6667  0.8322 
C:  0.3333  0.6667  0.9565 
Atom type 

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.

Horizontal:
Xmin:
Xmax:
Vertical:
Ymin:
Ymax:
 
Choose the polarization of the lasers.
I ∥ 
I ⊥ 
I Total 

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
E2u
292
292
292
292
1.927e+36
0.0
1.330e+36
0.0
3.257e+36
0.0
5
E2u
292
292
292
292
6
E2g
303
303
303
303
5.510e+38
0.3
4.375e+38
0.2
9.885e+38
0.5
7
E2g
303
303
303
303
5.435e+38
0.3
7.240e+38
0.4
1.267e+39
0.7
8
E1g
481
481
481
481
1.171e+39
0.6
1.689e+39
0.9
2.860e+39
1.5
9
E1g
481
481
481
481
1.171e+39
0.6
1.532e+39
0.8
2.703e+39
1.4
10
B1g
494
494
494
494
11
E1u
495
495
495
495
12
E1u
495
495
495
495
13
B2u
500
500
500
500
14
E2u
549
549
549
549
15
E2u
549
549
549
549
16
A2u
889
889
889
889
4.044e+36
0.0
6.654e+36
0.0
1.070e+37
0.0
17
A1g
894
894
894
894
1.718e+39
0.9
6.787e+37
0.0
1.786e+39
1.0
18
B2u
1077
1077
1077
1077
19
E2g
1232
1232
1232
1232
1.077e+40
5.7
8.237e+39
4.4
1.901e+40
10.1
20
E2g
1232
1232
1232
1232
1.076e+40
5.7
1.464e+40
7.8
2.540e+40
13.5
21
E1u
1246
1246
1246
1246
1.356e+36
0.0
1.158e+36
0.0
2.514e+36
0.0
22
E1u
1246
1246
1246
1246
23
E1g
1260
1260
1260
1260
8.937e+38
0.5
1.229e+39
0.7
2.123e+39
1.1
24
E1g
1260
1260
1260
1260
8.939e+38
0.5
1.229e+39
0.7
2.123e+39
1.1
25
B1g
1270
1270
1270
1270
1.351e+36
0.0
1.492e+36
0.0
2.844e+36
0.0
26
A1g
1299
1299
1299
1299
8.305e+40
44.3
5.266e+40
28.1
1.357e+41
72.3
27
E2g
1301
1301
1301
1301
8.617e+40
45.9
8.165e+40
43.5
1.678e+41
89.4
28
E2g
1301
1301
1301
1301
8.618e+40
45.9
1.015e+41
54.1
1.876e+41
100.0
29
E2u
1302
1302
1302
1302
30
E2u
1302
1302
1302
1302
31
B2u
1318
1318
1318
1318
32
A2u
1322
1322
1322
1322
2.242e+36
0.0
3.690e+36
0.0
5.932e+36
0.0
33
E1g
1331
1331
1331
1331
6.865e+40
36.6
9.448e+40
50.3
1.631e+41
86.9
34
E1g
1331
1331
1331
1331
6.865e+40
36.6
9.432e+40
50.3
1.630e+41
86.9
35
A1g
1332
1332
1332
1332
9.846e+40
52.5
7.383e+40
39.3
1.723e+41
91.8
36
B1g
1342
1342
1342
1342
1.530e+36
0.0
1.690e+36
0.0
3.220e+36
0.0
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.