-    ROOSEVELTITE     -    BiAsO4

he 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:  14  P2_1/n 
Lattice parameters (Å):  6.8790  7.1590  6.7320 
Angles (°):  90  104.84  90 

Symmetry (theoretical): 

Space group:  14  P2_1/n 
Lattice parameters (Å):  6.6844  6.9998  6.5973 
Angles (°):  90  105.04  90 

Cell contents: 

Number of atoms:  24 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Bi:  0.2794  0.1353  0.0847 
As:  0.2984  0.1626  0.6123 
O:  0.2625  0.9963  0.4223 
O:  0.3922  0.3597  0.5195 
O:  0.4789  0.1044  0.8411 
O:  0.1049  0.2094  0.7273 
Bi:  0.2206  0.6353  0.4153 
As:  0.2016  0.6626  0.8877 
O:  0.2375  0.4963  0.0777 
O:  0.1078  0.8597  0.9805 
O:  0.0211  0.6044  0.6589 
O:  0.3951  0.7094  0.7727 
Bi:  0.7206  0.8647  0.9153 
As:  0.7016  0.8374  0.3877 
O:  0.7375  0.0037  0.5777 
O:  0.6078  0.6403  0.4805 
O:  0.5211  0.8956  0.1589 
O:  0.8951  0.7906  0.2727 
Bi:  0.7794  0.3647  0.5847 
As:  0.7984  0.3374  0.1123 
O:  0.7625  0.5037  0.9223 
O:  0.8922  0.1403  0.0195 
O:  0.9789  0.3956  0.3411 
O:  0.6049  0.2906  0.2273 
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
60
60
60
60
2.761e+40
3.2
1.795e+40
2.1
4.556e+40
5.3
5
Au
65
65
68
65
6
Bg
71
71
71
71
8.637e+38
0.1
1.188e+39
0.1
2.051e+39
0.2
7
Bu
75
75
75
75
8
Bg
75
75
75
75
1.113e+40
1.3
1.842e+40
2.1
2.955e+40
3.4
9
Au
75
81
76
79
10
Ag
81
82
81
81
5.016e+40
5.8
1.075e+40
1.3
6.091e+40
7.1
11
Ag
92
92
92
92
8.607e+40
10.0
1.235e+39
0.1
8.730e+40
10.2
12
Bg
93
93
93
93
4.891e+39
0.6
5.309e+39
0.6
1.020e+40
1.2
13
Bu
97
109
97
102
14
Bg
109
120
109
109
1.132e+39
0.1
1.557e+39
0.2
2.689e+39
0.3
15
Au
120
130
128
120
16
Au
130
135
135
130
17
Ag
135
136
138
135
5.949e+40
6.9
3.723e+39
0.4
6.321e+40
7.4
18
Ag
138
138
141
138
5.645e+40
6.6
1.066e+40
1.2
6.711e+40
7.8
19
Bu
141
148
153
142
20
Bu
153
155
154
155
21
Au
155
159
159
157
22
Bg
159
159
164
159
9.943e+39
1.2
1.123e+40
1.3
2.117e+40
2.5
23
Bu
164
167
167
167
24
Bg
167
169
169
169
1.246e+40
1.4
1.490e+40
1.7
2.736e+40
3.2
25
Ag
169
173
173
173
4.565e+40
5.3
3.447e+40
4.0
8.012e+40
9.3
26
Ag
173
193
183
195
3.404e+40
4.0
4.751e+39
0.6
3.879e+40
4.5
27
Bu
195
196
195
197
28
Bg
197
197
197
203
8.278e+39
1.0
8.947e+39
1.0
1.722e+40
2.0
29
Au
203
203
206
206
30
Bg
206
206
210
221
2.349e+39
0.3
2.639e+39
0.3
4.989e+39
0.6
31
Au
221
221
225
227
32
Bu
227
228
227
228
33
Ag
228
228
228
233
3.022e+40
3.5
1.231e+40
1.4
4.253e+40
4.9
34
Bg
258
258
258
258
6.988e+39
0.8
1.144e+40
1.3
1.843e+40
2.1
35
Au
258
258
261
258
36
Au
273
273
274
273
37
Ag
285
285
285
285
2.105e+40
2.4
9.104e+39
1.1
3.016e+40
3.5
38
Au
318
318
319
318
39
Bu
319
320
320
320
40
Ag
320
332
332
320
9.122e+40
10.6
5.155e+39
0.6
9.638e+40
11.2
41
Bg
332
333
345
332
1.919e+40
2.2
2.269e+40
2.6
4.188e+40
4.9
42
Ag
345
345
345
345
1.368e+41
15.9
3.457e+40
4.0
1.713e+41
19.9
43
Bu
345
347
357
366
44
Ag
373
373
373
373
4.455e+40
5.2
3.013e+40
3.5
7.468e+40
8.7
45
Au
375
375
376
375
46
Bg
376
376
390
376
4.953e+39
0.6
5.765e+39
0.7
1.072e+40
1.2
47
Bu
390
401
392
390
48
Bg
401
404
401
401
1.200e+40
1.4
2.025e+40
2.4
3.226e+40
3.8
49
Ag
404
409
404
404
7.712e+40
9.0
4.023e+40
4.7
1.174e+41
13.7
50
Bu
411
419
411
419
51
Au
419
438
426
438
52
Bg
438
438
438
438
5.400e+39
0.6
5.838e+39
0.7
1.124e+40
1.3
53
Ag
438
454
438
439
1.828e+40
2.1
1.367e+40
1.6
3.195e+40
3.7
54
Bu
454
468
454
468
55
Bg
468
475
468
475
2.891e+39
0.3
3.615e+39
0.4
6.506e+39
0.8
56
Au
475
481
482
508
57
Au
743
743
751
743
58
Bu
751
767
764
774
59
Ag
774
774
774
774
3.475e+40
4.0
4.531e+39
0.5
3.928e+40
4.6
60
Bu
789
789
789
789
61
Bg
789
793
789
789
4.192e+39
0.5
5.397e+39
0.6
9.589e+39
1.1
62
Au
793
796
801
793
63
Ag
801
801
802
801
3.205e+41
37.3
2.296e+40
2.7
3.435e+41
40.0
64
Bg
802
802
810
802
3.298e+39
0.4
3.979e+39
0.5
7.277e+39
0.8
65
Au
811
811
811
811
66
Bu
811
812
823
811
67
Ag
823
823
835
823
1.766e+41
20.5
9.580e+40
11.1
2.724e+41
31.7
68
Bu
835
837
837
837
69
Ag
837
839
839
839
8.532e+41
99.3
6.329e+39
0.7
8.595e+41
100.0
70
Bg
839
840
840
840
1.378e+40
1.6
1.875e+40
2.2
3.253e+40
3.8
71
Bg
840
845
840
845
3.479e+40
4.0
3.712e+40
4.3
7.192e+40
8.4
72
Au
845
873
873
886
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.