-    PYRARGYRITE     -    Ag3SbS3

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:  161  R3c 
Lattice parameters (Å):  11.0464  11.0464  8.7211 
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  161  R3c 
Lattice parameters (Å):  6.7724  6.7724  6.7724 
Angles (°):  100.81  100.81  100.81 

Cell contents: 

Number of atoms:  14 
Number of atom types:  3 
Chemical composition:  0 

Atomic positions (theoretical):

Sb:  0.0196  0.0196  0.0196 
Ag:  0.4360  0.2322  0.9247 
S:  0.6036  0.2452  0.2767 
Ag:  0.2322  0.9247  0.4360 
S:  0.2452  0.2767  0.6036 
Sb:  0.5196  0.5196  0.5196 
Ag:  0.4247  0.7322  0.9360 
S:  0.7767  0.7452  0.1036 
Ag:  0.9247  0.4360  0.2322 
S:  0.2767  0.6036  0.2452 
Ag:  0.7322  0.9360  0.4247 
S:  0.7452  0.1036  0.7767 
Ag:  0.9360  0.4247  0.7322 
S:  0.1036  0.7767  0.7452 
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
0
0
0
0
2
0
0
0
0
3
0
0
0
0
4
6
6
6
6
5
6
11
11
6
6
18
18
18
18
7
33
33
33
33
1.815e+41
0.7
2.960e+41
1.2
4.774e+41
2.0
8
33
34
34
33
1.815e+41
0.7
2.254e+41
0.9
4.068e+41
1.7
9
38
38
38
41
1.724e+42
7.1
1.017e+41
0.4
1.826e+42
7.5
10
49
49
49
49
3.014e+41
1.2
4.358e+41
1.8
7.371e+41
3.0
11
49
49
49
49
3.014e+41
1.2
4.119e+41
1.7
7.133e+41
2.9
12
50
50
50
50
13
54
54
54
54
4.263e+41
1.8
7.103e+41
2.9
1.137e+42
4.7
14
54
54
54
54
4.263e+41
1.8
5.013e+41
2.1
9.275e+41
3.8
15
56
56
56
56
1.092e+43
44.8
2.403e+41
1.0
1.116e+43
45.8
16
58
58
58
58
17
70
70
70
70
1.004e+42
4.1
1.683e+42
6.9
2.687e+42
11.0
18
70
70
70
70
1.004e+42
4.1
1.146e+42
4.7
2.150e+42
8.8
19
93
93
93
93
4.951e+41
2.0
8.355e+41
3.4
1.331e+42
5.5
20
93
93
93
93
4.951e+41
2.0
5.218e+41
2.1
1.017e+42
4.2
21
111
111
111
111
2.205e+41
0.9
2.500e+41
1.0
4.705e+41
1.9
22
111
113
113
111
2.205e+41
0.9
1.905e+41
0.8
4.111e+41
1.7
23
115
115
115
117
8.853e+42
36.4
2.129e+41
0.9
9.066e+42
37.2
24
124
124
124
124
25
204
204
204
204
1.005e+43
41.3
3.758e+41
1.5
1.043e+43
42.8
26
247
247
247
247
1.661e+41
0.7
1.767e+41
0.7
3.427e+41
1.4
27
247
248
248
247
1.661e+41
0.7
1.715e+41
0.7
3.376e+41
1.4
28
250
250
250
250
2.285e+41
0.9
3.360e+41
1.4
5.645e+41
2.3
29
250
253
253
250
2.285e+41
0.9
3.107e+41
1.3
5.392e+41
2.2
30
253
254
254
253
31
254
254
254
254
9.219e+40
0.4
1.324e+41
0.5
2.246e+41
0.9
32
254
262
262
254
9.219e+40
0.4
6.971e+40
0.3
1.619e+41
0.7
33
285
285
285
285
1.461e+41
0.6
2.462e+41
1.0
3.923e+41
1.6
34
285
285
285
285
5.493e+39
0.0
5.609e+39
0.0
1.110e+40
0.0
35
285
285
285
285
36
292
292
292
296
2.156e+43
88.6
1.072e+40
0.0
2.157e+43
88.6
37
296
296
296
296
1.663e+42
6.8
2.794e+42
11.5
4.457e+42
18.3
38
296
300
300
299
1.663e+42
6.8
1.881e+42
7.7
3.544e+42
14.6
39
300
306
306
315
2.422e+43
99.5
1.220e+41
0.5
2.434e+43
100.0
40
326
326
326
326
7.032e+41
2.9
1.180e+42
4.8
1.883e+42
7.7
41
326
330
330
326
7.032e+41
2.9
6.934e+41
2.8
1.397e+42
5.7
42
330
330
330
330
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.