-    PROUSTITE     -    Ag3AsS3

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):  10.7680  10.7680  8.7200 
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  161  R3c 
Lattice parameters (Å):  6.7582  6.7582  6.7582 
Angles (°):  102.72  102.72  102.72 

Cell contents: 

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

Atomic positions (theoretical):

Ag:  0.4617  0.2426  0.9197 
As:  0.0151  0.0151  0.0151 
S:  0.5978  0.2603  0.2893 
Ag:  0.2426  0.9197  0.4617 
S:  0.2603  0.2893  0.5978 
Ag:  0.4197  0.7426  0.9617 
As:  0.5151  0.5151  0.5151 
S:  0.7893  0.7603  0.0978 
Ag:  0.9197  0.4617  0.2426 
S:  0.2893  0.5978  0.2603 
Ag:  0.7426  0.9617  0.4197 
S:  0.7603  0.0978  0.7893 
Ag:  0.9617  0.4197  0.7426 
S:  0.0978  0.7893  0.7603 
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
E
-23
-23
-23
-23
2
E
-23
-20
-20
-23
3
Ac
0
0
0
0
4
Ac
0
0
0
0
5
Ac
0
0
0
0
6
A2
6
6
6
6
7
E
29
29
29
29
1.146e+41
0.5
1.931e+41
0.8
3.077e+41
1.3
8
E
29
29
29
29
1.146e+41
0.5
1.192e+41
0.5
2.338e+41
1.0
9
A1
36
36
36
41
5.165e+41
2.2
5.611e+40
0.2
5.726e+41
2.5
10
E
42
42
42
42
1.004e+41
0.4
1.443e+41
0.6
2.447e+41
1.1
11
E
42
43
43
42
1.004e+41
0.4
1.419e+41
0.6
2.423e+41
1.0
12
A1
44
44
44
44
4.998e+42
21.5
3.240e+41
1.4
5.322e+42
22.9
13
A2
44
44
44
46
14
E
48
48
48
48
2.410e+41
1.0
2.898e+41
1.2
5.308e+41
2.3
15
E
48
50
50
48
2.410e+41
1.0
4.003e+41
1.7
6.412e+41
2.8
16
A2
59
59
59
59
17
E
67
67
67
67
2.794e+41
1.2
3.630e+41
1.6
6.423e+41
2.8
18
E
67
67
67
67
2.794e+41
1.2
4.415e+41
1.9
7.210e+41
3.1
19
E
106
106
106
106
6.292e+40
0.3
7.636e+40
0.3
1.393e+41
0.6
20
E
106
107
107
106
6.293e+40
0.3
9.498e+40
0.4
1.579e+41
0.7
21
E
124
124
124
124
1.617e+41
0.7
1.967e+41
0.8
3.584e+41
1.5
22
E
124
125
125
124
1.617e+41
0.7
1.261e+41
0.5
2.878e+41
1.2
23
A1
145
145
145
145
1.549e+42
6.7
1.385e+41
0.6
1.688e+42
7.3
24
A2
151
151
151
151
25
A1
213
213
213
213
4.504e+42
19.4
3.409e+41
1.5
4.845e+42
20.9
26
E
238
238
238
238
9.868e+39
0.0
1.606e+40
0.1
2.593e+40
0.1
27
E
238
239
239
238
9.804e+39
0.0
1.139e+40
0.0
2.119e+40
0.1
28
E
239
239
239
239
1.270e+41
0.5
1.228e+41
0.5
2.498e+41
1.1
29
E
239
239
239
239
1.269e+41
0.5
1.654e+41
0.7
2.923e+41
1.3
30
A2
257
257
257
257
31
E
271
271
271
271
6.143e+41
2.6
7.716e+41
3.3
1.386e+42
6.0
32
E
271
280
280
271
6.143e+41
2.6
4.885e+41
2.1
1.103e+42
4.7
33
A1
280
281
281
282
1.236e+42
5.3
2.642e+40
0.1
1.263e+42
5.4
34
A2
282
282
282
285
35
E
292
292
292
292
3.737e+40
0.2
4.877e+40
0.2
8.615e+40
0.4
36
E
292
292
292
292
3.737e+40
0.2
4.992e+40
0.2
8.729e+40
0.4
37
E
321
321
321
321
9.293e+41
4.0
1.513e+42
6.5
2.443e+42
10.5
38
E
321
328
328
321
9.293e+41
4.0
1.145e+42
4.9
2.075e+42
8.9
39
E
340
340
340
340
1.641e+41
0.7
2.006e+41
0.9
3.647e+41
1.6
40
E
340
344
344
340
1.641e+41
0.7
2.694e+41
1.2
4.335e+41
1.9
41
A1
344
344
344
350
2.321e+43
100.0
7.872e+39
0.0
2.322e+43
100.0
42
A2
354
354
354
354
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.