-    ARTROEITE     -    PbAlF3(OH)2

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. Computed using Teter "extended norm-conserving" pseudopotentials. 

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:  P-1 
Lattice parameters (Å):  6.2700  6.8210  5.0570 
Angles (°):  90.7  107.7  104.5 

Symmetry (theoretical): 

Space group:  P-1 
Lattice parameters (Å):  6.1443  6.7104  4.9069 
Angles (°):  90.4  107.8  104.6 

Cell contents: 

Number of atoms:  18 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Pb:  0.3116  0.1911  0.1977 
Al:  0.8122  0.3282  0.8380 
F:  0.7940  0.1379  0.5686 
F:  0.7393  0.4919  0.5537 
F:  0.5080  0.2307  0.8010 
O:  0.8617  0.5511  0.1019 
O:  0.8960  0.1420  0.1015 
H:  0.8125  0.5282  0.2776 
H:  0.8560  0.1433  0.2832 
Pb:  0.6884  0.8089  0.8023 
Al:  0.1878  0.6718  0.1620 
F:  0.2060  0.8621  0.4314 
F:  0.2607  0.5081  0.4463 
F:  0.4920  0.7693  0.1990 
O:  0.1383  0.4489  0.8981 
O:  0.1040  0.8580  0.8985 
H:  0.1875  0.4718  0.7224 
H:  0.1440  0.8567  0.7168 
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
57
57
57
57
8.515e+39
5.6
7.766e+39
5.1
1.628e+40
10.7
5
Ag
75
75
75
75
3.944e+39
2.6
3.455e+39
2.3
7.399e+39
4.9
6
Ag
90
90
90
90
1.773e+40
11.6
3.115e+39
2.0
2.084e+40
13.7
7
Au
97
97
98
101
8
Ag
101
101
101
110
1.473e+39
1.0
1.397e+39
0.9
2.871e+39
1.9
9
Au
110
110
120
118
10
Au
121
148
144
129
11
Ag
148
161
148
148
9.115e+39
6.0
6.054e+39
4.0
1.517e+40
10.0
12
Au
168
168
174
168
13
Ag
174
174
186
174
1.625e+39
1.1
1.767e+39
1.2
3.392e+39
2.2
14
Au
187
192
192
188
15
Au
196
201
208
210
16
Ag
210
210
210
212
2.660e+39
1.7
3.218e+39
2.1
5.878e+39
3.9
17
Ag
219
219
219
219
2.169e+40
14.2
1.476e+39
1.0
2.317e+40
15.2
18
Ag
238
238
238
238
1.361e+39
0.9
1.602e+39
1.1
2.963e+39
1.9
19
Au
244
245
247
247
20
Ag
278
278
278
278
3.514e+39
2.3
5.016e+38
0.3
4.016e+39
2.6
21
Ag
291
291
291
291
1.782e+39
1.2
1.175e+39
0.8
2.958e+39
1.9
22
Au
322
323
324
322
23
Au
335
335
341
358
24
Ag
358
358
358
361
2.943e+39
1.9
2.600e+39
1.7
5.542e+39
3.6
25
Ag
361
361
361
361
1.206e+39
0.8
1.358e+39
0.9
2.563e+39
1.7
26
Au
368
368
370
368
27
Ag
373
373
373
373
28
Au
373
382
375
382
1.699e+39
1.1
2.585e+39
1.7
4.284e+39
2.8
29
Au
399
404
416
400
30
Ag
418
418
418
418
6.327e+39
4.2
2.443e+38
0.2
6.571e+39
4.3
31
Ag
433
433
433
433
8.435e+38
0.6
9.192e+38
0.6
1.763e+39
1.2
32
Au
443
449
459
452
33
Ag
476
476
476
476
2.363e+40
15.5
2.676e+39
1.8
2.631e+40
17.3
34
Au
488
499
492
492
35
Au
514
518
514
518
36
Ag
518
518
518
546
2.462e+39
1.6
1.036e+39
0.7
3.498e+39
2.3
37
Au
547
549
549
549
38
Ag
549
561
567
560
1.003e+40
6.6
1.045e+40
6.9
2.048e+40
13.4
39
Au
585
592
592
590
40
Ag
592
593
601
592
2.313e+40
15.2
4.343e+39
2.9
2.747e+40
18.0
41
Au
605
618
618
617
42
Ag
618
650
630
618
6.858e+39
4.5
7.688e+39
5.0
1.455e+40
9.5
43
Au
881
882
897
881
44
Ag
897
897
904
897
4.075e+39
2.7
4.027e+39
2.6
8.102e+39
5.3
45
Au
927
944
927
936
46
Ag
965
965
965
965
6.664e+39
4.4
2.773e+39
1.8
9.437e+39
6.2
47
Au
1012
1017
1024
1012
48
Ag
1046
1046
1046
1046
3.113e+39
2.0
2.811e+38
0.2
3.394e+39
2.2
49
Au
1098
1100
1100
1100
50
Ag
1100
1102
1106
1102
4.402e+39
2.9
1.177e+39
0.8
5.579e+39
3.7
51
Ag
3109
3109
3109
3109
7.690e+40
50.5
2.180e+40
14.3
9.871e+40
64.8
52
Au
3110
3117
3113
3123
53
Ag
3165
3165
3165
3165
1.265e+41
83.0
2.587e+40
17.0
1.524e+41
100.0
54
Au
3165
3194
3166
3236
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.