-    SULFUR     -    S8

The crystal structure is fully relaxed (both unit cell parameters and atomic positions under symmetry constraints) starting from an experimental structure similar to the one reported in AMCSD

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:  70  Fddd 
Lattice parameters (Å):  10.4670  12.8700  24.4930 
Angles (°):  90  90  90 

Symmetry (theoretical): 

Space group:  70  Fddd 
Lattice parameters (Å):  0.5292  0.5292  0.5292 
Angles (°):  75.1  68.6  36.3 

Cell contents: 

Number of atoms:  32 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

S:  0.0448  0.8513  0.8614 
S:  0.9552  0.1487  0.1386 
S:  0.7425  0.8614  0.8513 
S:  0.2575  0.1386  0.1487 
S:  0.8614  0.7425  0.0448 
S:  0.1386  0.2575  0.9552 
S:  0.8513  0.0448  0.7425 
S:  0.1487  0.9552  0.2575 
S:  0.3240  0.8297  0.7373 
S:  0.6760  0.1703  0.2627 
S:  0.6090  0.7373  0.8297 
S:  0.3910  0.2627  0.1703 
S:  0.7373  0.6090  0.3240 
S:  0.2627  0.3910  0.6760 
S:  0.8297  0.3240  0.6090 
S:  0.1703  0.6760  0.3910 
S:  0.2739  0.7301  0.6910 
S:  0.7261  0.2699  0.3090 
S:  0.8051  0.6910  0.7301 
S:  0.1949  0.3090  0.2699 
S:  0.6910  0.8051  0.2739 
S:  0.3090  0.1949  0.7261 
S:  0.7301  0.2739  0.8051 
S:  0.2699  0.7261  0.1949 
S:  0.2526  0.0100  0.5634 
S:  0.7474  0.9900  0.4366 
S:  0.6740  0.5634  0.0100 
S:  0.3260  0.4366  0.9900 
S:  0.5634  0.6740  0.2526 
S:  0.4366  0.3260  0.7474 
S:  0.0100  0.2526  0.6740 
S:  0.9900  0.7474  0.3260 
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
-27
-27
-27
-27
2
-16
-16
-16
-16
3
-5
-5
-5
-5
4
0
0
0
0
5
0
0
0
0
6
0
0
0
0
7
19
19
19
19
8
23
23
23
23
9
25
25
25
25
10
27
27
27
27
11
32
32
32
32
12
35
35
35
35
13
37
37
37
37
14
38
39
38
38
15
39
39
39
39
16
42
42
42
42
17
42
42
42
42
18
42
42
42
42
19
43
43
43
43
20
44
44
44
44
21
47
47
47
47
22
48
48
48
48
23
51
51
51
51
24
55
55
55
55
25
69
69
69
69
26
74
74
74
74
27
74
74
74
74
28
74
74
74
74
29
78
78
78
78
30
80
80
80
80
31
82
82
82
82
32
83
83
83
83
33
134
134
134
134
34
136
136
136
136
35
137
137
137
137
36
138
138
138
138
37
139
139
139
139
38
140
140
140
140
39
140
140
140
140
40
141
141
141
141
41
176
176
176
176
42
178
178
178
178
43
179
179
179
181
44
181
181
181
181
45
187
187
188
187
46
188
188
188
188
47
189
190
189
189
48
190
190
190
190
49
207
207
207
207
50
209
209
209
209
51
211
211
211
211
52
213
213
213
213
53
220
220
220
220
54
221
221
221
221
55
221
221
221
221
56
223
223
224
223
57
234
234
234
234
58
238
238
238
238
59
240
240
240
240
60
242
242
242
242
61
242
242
242
242
62
243
243
243
243
63
246
246
246
246
64
247
247
247
247
65
370
370
370
370
66
371
371
371
371
67
372
372
372
372
68
372
372
372
372
69
397
397
397
397
70
398
398
398
398
71
398
398
398
398
72
399
399
399
399
73
399
399
399
399
74
400
400
400
400
75
401
401
401
401
76
401
401
401
401
77
453
453
453
453
78
454
454
454
454
79
454
454
454
454
80
455
455
455
455
81
455
455
455
455
82
456
456
456
456
83
457
457
457
457
84
458
458
458
458
85
461
461
461
461
86
461
461
461
461
87
461
461
461
461
88
462
462
462
462
89
463
463
463
463
90
463
463
463
463
91
464
464
464
464
92
465
465
465
465
93
470
470
470
470
94
471
471
471
471
95
472
472
472
472
96
473
473
473
473
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.