-    NATROALUNITE     -    NaAl3(SO4)2(OH)6

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:  166  R-3m 
Lattice parameters (Å):  6.9749  6.9749  17.3150 
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  166  R-3m 
Lattice parameters (Å):  6.6583  6.6583  6.6583 
Angles (°):  62.01  62.01  62.01 

Cell contents: 

Number of atoms:  26 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Na:  0.0000  0.0000  0.0000 
Al:  0.5000  0.0000  0.0000 
S:  0.3110  0.3110  0.3110 
O:  0.4022  0.4022  0.4022 
O:  0.1638  0.5150  0.1638 
O:  0.2635  0.8875  0.2635 
H:  0.3139  0.7109  0.3139 
Al:  0.0000  0.0000  0.5000 
O:  0.5150  0.1638  0.1638 
O:  0.8875  0.2635  0.2635 
H:  0.7109  0.3139  0.3139 
Al:  0.0000  0.5000  0.0000 
O:  0.1638  0.1638  0.5150 
O:  0.2635  0.2635  0.8875 
H:  0.3139  0.3139  0.7109 
S:  0.6890  0.6890  0.6890 
O:  0.5978  0.5978  0.5978 
O:  0.8362  0.4850  0.8362 
O:  0.7365  0.1125  0.7365 
H:  0.6861  0.2891  0.6861 
O:  0.4850  0.8362  0.8362 
O:  0.1125  0.7365  0.7365 
H:  0.2891  0.6861  0.6861 
O:  0.8362  0.8362  0.4850 
O:  0.7365  0.7365  0.1125 
H:  0.6861  0.6861  0.2891 
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
0
0
0
0
2
0
0
0
0
3
0
0
0
0
4
68
68
68
68
5
68
90
90
68
6
109
109
109
134
7
166
166
166
166
8
169
169
169
169
1.118e+39
0.8
1.281e+39
0.9
2.400e+39
1.7
9
169
169
169
169
1.118e+39
0.8
1.875e+39
1.3
2.993e+39
2.1
10
171
171
171
171
11
198
198
198
198
12
198
198
198
198
13
222
222
222
222
14
222
224
224
222
15
234
234
234
234
5.708e+38
0.4
5.936e+38
0.4
1.164e+39
0.8
16
234
234
234
234
5.708e+38
0.4
7.878e+38
0.5
1.359e+39
0.9
17
242
242
242
242
1.557e+40
10.8
5.632e+38
0.4
1.614e+40
11.2
18
265
265
265
265
1.287e+39
0.9
1.126e+39
0.8
2.414e+39
1.7
19
265
265
265
265
1.287e+39
0.9
1.961e+39
1.4
3.249e+39
2.2
20
292
292
292
292
21
298
298
298
298
22
298
308
308
298
23
312
312
312
312
24
335
335
335
335
25
335
341
341
335
26
341
352
352
341
6.712e+39
4.6
1.039e+37
0.0
6.723e+39
4.7
27
361
361
361
361
28
361
378
378
361
29
415
415
415
415
3.415e+39
2.4
2.827e+39
2.0
6.242e+39
4.3
30
415
415
415
415
3.415e+39
2.4
4.239e+39
2.9
7.653e+39
5.3
31
416
416
416
469
32
472
472
472
472
4.497e+39
3.1
3.641e+39
2.5
8.138e+39
5.6
33
472
472
472
472
4.497e+39
3.1
5.491e+39
3.8
9.988e+39
6.9
34
476
476
476
476
35
476
477
477
476
36
479
479
479
479
37
520
520
520
536
38
536
536
536
537
8.212e+39
5.7
5.904e+37
0.0
8.271e+39
5.7
39
569
569
569
570
40
597
597
597
597
4.441e+39
3.1
5.107e+39
3.5
9.548e+39
6.6
41
597
597
597
597
4.441e+39
3.1
7.326e+39
5.1
1.177e+40
8.1
42
602
602
602
602
43
602
614
614
602
44
631
631
631
631
45
631
632
632
631
46
632
634
634
632
1.106e+40
7.7
2.542e+39
1.8
1.360e+40
9.4
47
634
634
634
634
1.768e+39
1.2
2.229e+39
1.5
3.997e+39
2.8
48
634
638
638
634
1.768e+39
1.2
2.840e+39
2.0
4.608e+39
3.2
49
638
652
652
653
50
655
655
655
655
51
655
665
665
655
52
665
697
697
665
53
708
708
708
716
54
716
716
716
716
2.067e+38
0.1
2.035e+38
0.1
4.102e+38
0.3
55
716
716
716
794
2.067e+38
0.1
2.829e+38
0.2
4.896e+38
0.3
56
796
796
796
796
57
796
808
808
796
58
915
915
915
915
4.326e+39
3.0
4.581e+37
0.0
4.372e+39
3.0
59
1007
1007
1007
1008
60
1008
1008
1008
1008
1.340e+41
92.7
3.447e+36
0.0
1.340e+41
92.7
61
1056
1056
1056
1056
62
1102
1102
1102
1102
2.886e+39
2.0
2.921e+39
2.0
5.806e+39
4.0
63
1102
1102
1102
1102
2.886e+39
2.0
4.454e+39
3.1
7.340e+39
5.1
64
1107
1107
1107
1107
65
1107
1128
1128
1107
66
1128
1136
1136
1128
67
1136
1139
1139
1136
1.196e+40
8.3
2.344e+39
1.6
1.430e+40
9.9
68
1139
1181
1181
1181
69
1181
1181
1181
1181
1.931e+39
1.3
2.455e+39
1.7
4.386e+39
3.0
70
1181
1185
1185
1186
1.931e+39
1.3
2.995e+39
2.1
4.926e+39
3.4
71
1186
1186
1186
1186
72
1186
1192
1192
1228
73
3283
3283
3283
3283
3.344e+40
23.1
4.914e+40
34.0
8.258e+40
57.1
74
3283
3283
3283
3283
3.344e+40
23.1
2.668e+40
18.5
6.012e+40
41.6
75
3290
3290
3290
3290
76
3290
3329
3329
3290
77
3360
3360
3360
3367
78
3367
3367
3367
3395
1.442e+41
99.8
2.985e+38
0.2
1.445e+41
100.0
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.