-    ORPIMENT     -    As2S3

Theoretical atomic positions and lattice parameters at experimental volum from 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:  14  P2_1/n 
Lattice parameters (Å):  11.4750  9.5770  4.2560 
Angles (°):  90.0  90.7  90.0 

Symmetry (theoretical): 

Space group:  14  P2_1/n 
Lattice parameters (Å):  9.8824  10.1720  4.6526 
Angles (°):  90.0  90.4  90.0 

Cell contents: 

Number of atoms:  20 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

As:  0.2822  0.1336  0.7083 
As:  0.4257  0.3598  0.2143 
S:  0.4365  0.1411  0.3529 
S:  0.2665  0.3536  0.8538 
S:  0.1035  0.1636  0.4037 
As:  0.2178  0.6336  0.7917 
As:  0.0743  0.8598  0.2857 
S:  0.0635  0.6411  0.1471 
S:  0.2335  0.8536  0.6462 
S:  0.3965  0.6636  0.0963 
As:  0.7178  0.8664  0.2917 
As:  0.5743  0.6402  0.7857 
S:  0.5635  0.8589  0.6471 
S:  0.7335  0.6464  0.1462 
S:  0.8965  0.8364  0.5963 
As:  0.7822  0.3664  0.2083 
As:  0.9257  0.1402  0.7143 
S:  0.9365  0.3589  0.8529 
S:  0.7665  0.1464  0.3538 
S:  0.6035  0.3364  0.9037 
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
Ag
17
17
17
17
5
Ag
28
28
28
28
4.708e+41
3.3
2.590e+41
1.8
7.298e+41
5.2
6
Ag
57
57
57
57
1.246e+41
0.9
9.227e+39
0.1
1.338e+41
0.9
7
Bg
61
61
61
61
1.441e+40
0.1
2.432e+40
0.2
3.873e+40
0.3
8
Au
64
64
65
64
9
Bg
72
72
72
72
3.084e+41
2.2
4.769e+41
3.4
7.853e+41
5.6
10
Bu
75
75
75
76
11
Au
79
79
79
79
12
Ag
79
79
82
79
2.290e+42
16.2
6.957e+41
4.9
2.986e+42
21.2
13
Au
83
83
91
83
14
Bu
91
91
92
92
15
Bg
92
92
94
94
1.006e+40
0.1
1.238e+40
0.1
2.244e+40
0.2
16
Bg
101
101
101
101
2.343e+40
0.2
3.902e+40
0.3
6.245e+40
0.4
17
Ag
112
112
112
112
3.301e+41
2.3
8.729e+40
0.6
4.173e+41
3.0
18
Au
115
115
121
115
19
Bg
121
121
125
121
1.375e+40
0.1
2.007e+40
0.1
3.382e+40
0.2
20
Au
129
129
129
129
21
Bg
130
130
130
130
1.504e+41
1.1
1.793e+41
1.3
3.297e+41
2.3
22
Bu
132
133
132
135
23
Ag
135
135
135
135
1.583e+41
1.1
3.318e+40
0.2
1.915e+41
1.4
24
Bu
136
136
136
138
25
Au
141
141
141
141
26
Ag
149
149
149
149
3.405e+41
2.4
1.947e+41
1.4
5.352e+41
3.8
27
Au
152
152
152
152
28
Ag
153
153
153
153
1.367e+41
1.0
4.355e+40
0.3
1.803e+41
1.3
29
Ag
153
153
153
153
4.328e+40
0.3
4.925e+40
0.3
9.253e+40
0.7
30
Bu
154
161
154
155
31
Bg
162
162
162
162
1.844e+41
1.3
2.006e+41
1.4
3.851e+41
2.7
32
Bu
166
167
166
169
33
Bg
169
169
169
170
5.247e+41
3.7
7.750e+41
5.5
1.300e+42
9.2
34
Au
170
170
174
170
35
Ag
174
174
184
174
2.616e+42
18.5
8.169e+41
5.8
3.433e+42
24.3
36
Bu
184
184
185
184
37
Au
263
263
264
263
38
Ag
271
271
271
271
1.132e+43
80.2
2.792e+42
19.8
1.412e+43
100.0
39
Bu
281
283
281
283
40
Ag
283
284
283
284
7.321e+41
5.2
8.128e+41
5.8
1.545e+42
10.9
41
Bg
284
286
284
285
1.159e+42
8.2
1.372e+42
9.7
2.530e+42
17.9
42
Au
290
290
291
290
43
Bu
291
303
298
303
44
Bg
303
306
303
306
6.054e+40
0.4
6.709e+40
0.5
1.276e+41
0.9
45
Ag
306
307
306
311
5.591e+41
4.0
2.040e+41
1.4
7.631e+41
5.4
46
Au
311
311
321
311
47
Bu
321
321
325
325
48
Bg
325
325
327
329
1.177e+41
0.8
1.898e+41
1.3
3.074e+41
2.2
49
Au
330
330
332
330
50
Ag
332
332
338
332
3.872e+42
27.4
8.821e+40
0.6
3.960e+42
28.1
51
Bg
338
338
341
338
2.042e+41
1.4
2.307e+41
1.6
4.349e+41
3.1
52
Bu
341
341
346
343
53
Bg
352
352
352
352
1.161e+40
0.1
1.296e+40
0.1
2.457e+40
0.2
54
Ag
354
354
354
354
5.944e+41
4.2
1.535e+41
1.1
7.479e+41
5.3
55
Au
354
354
356
354
56
Bu
356
356
357
356
57
Bu
366
366
366
367
58
Ag
367
367
367
368
1.074e+42
7.6
1.204e+41
0.9
1.195e+42
8.5
59
Bg
368
368
368
371
1.808e+39
0.0
2.588e+39
0.0
4.396e+39
0.0
60
Au
374
374
376
374
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.