-    SINHALITE     -    AlMgBO4

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:  62  Pnma 
Lattice parameters (Å):  5.2272  3.0031  2.2903 
Angles (°):  90  90  90 

Symmetry (theoretical): 

Space group:  62  Pnma 
Lattice parameters (Å):  9.6930  5.5861  4.2718 
Angles (°):  90  90  90 

Cell contents: 

Number of atoms:  28 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Al:  0.0000  0.0000  0.0000 
Mg:  0.2750  0.2500  0.9852 
B:  0.0869  0.2500  0.4090 
O:  0.0809  0.2500  0.7427 
O:  0.4436  0.2500  0.2552 
O:  0.1494  0.0374  0.2644 
Al:  0.5000  0.0000  0.5000 
Mg:  0.2250  0.7500  0.4852 
B:  0.4131  0.7500  0.9090 
O:  0.4191  0.7500  0.2427 
O:  0.0564  0.7500  0.7552 
O:  0.3506  0.9626  0.7644 
Al:  0.0000  0.5000  0.0000 
Mg:  0.7250  0.7500  0.0148 
B:  0.9131  0.7500  0.5910 
O:  0.9191  0.7500  0.2573 
O:  0.5564  0.7500  0.7448 
O:  0.8506  0.5374  0.7356 
Al:  0.5000  0.5000  0.5000 
Mg:  0.7750  0.2500  0.5148 
B:  0.5869  0.2500  0.0910 
O:  0.5809  0.2500  0.7573 
O:  0.9436  0.2500  0.2448 
O:  0.6494  0.4626  0.2356 
O:  0.8506  0.9626  0.7356 
O:  0.6494  0.0374  0.2356 
O:  0.1494  0.4626  0.2644 
O:  0.3506  0.5374  0.7644 
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
Au
136
136
136
136
5
B3u
156
159
156
156
6
B3g
226
226
226
226
7.250e+37
0.7
9.969e+37
0.9
1.722e+38
1.6
7
B1u
227
227
227
228
8
Ag
235
235
235
235
4.608e+37
0.4
1.157e+37
0.1
5.766e+37
0.5
9
Au
249
249
249
249
10
B2u
263
263
274
263
11
Au
274
274
274
274
12
B2g
278
278
278
278
13
B2u
282
282
295
282
14
Ag
296
296
296
296
5.766e+38
5.3
4.177e+37
0.4
6.183e+38
5.7
15
B1u
304
304
304
305
16
B3u
310
313
310
310
17
B1g
322
322
322
322
1.179e+38
1.1
1.621e+38
1.5
2.800e+38
2.6
18
B2u
330
330
332
330
19
B2g
332
332
341
332
8.665e+37
0.8
1.191e+38
1.1
2.058e+38
1.9
20
B1u
341
341
345
343
21
Au
363
363
363
363
22
B3g
380
380
380
380
8.674e+37
0.8
1.193e+38
1.1
2.060e+38
1.9
23
Ag
381
381
381
381
3.776e+39
35.0
2.482e+38
2.3
4.025e+39
37.3
24
B1g
388
388
388
388
5.671e+38
5.3
7.798e+38
7.2
1.347e+39
12.5
25
B2g
388
388
388
388
4.373e+37
0.4
6.013e+37
0.6
1.039e+38
1.0
26
B3u
391
407
391
391
27
Ag
407
407
407
407
1.478e+38
1.4
3.737e+37
0.3
1.852e+38
1.7
28
B3g
407
413
407
407
8.108e+37
0.8
1.115e+38
1.0
1.926e+38
1.8
29
Ag
413
417
413
413
2.074e+39
19.2
1.768e+38
1.6
2.250e+39
20.9
30
B1g
417
423
417
417
3.691e+38
3.4
5.075e+38
4.7
8.767e+38
8.1
31
B2g
423
432
423
423
6.297e+38
5.8
8.659e+38
8.0
1.496e+39
13.9
32
B1u
432
437
432
440
33
B3u
440
452
440
450
34
Au
459
459
459
459
35
B2u
459
459
461
459
36
B1g
462
462
462
462
2.278e+38
2.1
3.132e+38
2.9
5.410e+38
5.0
37
B3g
471
471
471
471
38
B2g
472
472
472
472
2.615e+38
2.4
3.595e+38
3.3
6.210e+38
5.8
39
B3u
480
480
480
480
40
B1u
484
484
484
484
41
B3u
485
487
485
485
42
B1u
487
499
487
499
43
B2u
499
500
500
500
44
Au
500
501
501
501
45
Ag
501
508
508
508
3.550e+39
32.9
1.499e+39
13.9
5.049e+39
46.8
46
B2g
508
524
524
524
2.448e+39
22.7
3.366e+39
31.2
5.814e+39
53.9
47
B1g
524
528
534
539
1.258e+38
1.2
1.730e+38
1.6
2.988e+38
2.8
48
Au
539
539
539
550
49
B2u
550
550
554
554
50
B3g
554
554
559
555
5.449e+38
5.1
7.492e+38
7.0
1.294e+39
12.0
51
B1u
559
559
570
570
52
Au
570
570
574
577
53
B3u
577
578
577
581
54
B2u
581
581
583
583
55
B3u
583
605
605
584
56
B1u
605
610
609
621
57
Ag
621
621
621
622
3.975e+39
36.9
2.630e+38
2.4
4.238e+39
39.3
58
B2g
622
622
622
626
9.222e+38
8.6
1.268e+39
11.8
2.190e+39
20.3
59
B1u
691
691
691
691
60
B3u
691
699
691
699
61
B2u
699
704
704
704
62
Au
704
707
707
707
63
B3g
707
709
709
709
1.147e+39
10.6
1.577e+39
14.6
2.723e+39
25.3
64
B1g
709
712
731
740
2.172e+38
2.0
2.986e+38
2.8
5.158e+38
4.8
65
Ag
761
761
761
761
1.049e+40
97.3
2.893e+38
2.7
1.078e+40
100.0
66
B1u
776
776
776
782
67
B3u
782
782
782
791
68
Ag
791
791
791
792
2.161e+39
20.0
1.362e+37
0.1
2.175e+39
20.2
69
B2g
792
792
792
796
8.129e+37
0.8
1.118e+38
1.0
1.931e+38
1.8
70
B2g
799
799
799
799
1.539e+36
0.0
2.116e+36
0.0
3.655e+36
0.0
71
B3u
808
820
808
808
72
B1u
820
827
820
821
73
Ag
870
870
870
870
7.892e+39
73.2
2.455e+38
2.3
8.137e+39
75.5
74
B2g
881
881
881
881
1.945e+38
1.8
2.674e+38
2.5
4.619e+38
4.3
75
B3u
909
935
909
909
76
B2u
935
957
957
935
77
B3g
957
992
992
957
1.026e+39
9.5
1.411e+39
13.1
2.437e+39
22.6
78
Au
992
1009
1009
992
79
B1g
1009
1011
1011
1009
6.803e+38
6.3
9.354e+38
8.7
1.616e+39
15.0
80
B1u
1011
1016
1060
1020
81
Ag
1060
1060
1069
1060
5.362e+39
49.7
6.115e+37
0.6
5.423e+39
50.3
82
B2g
1069
1069
1093
1069
1.031e+37
0.1
1.418e+37
0.1
2.448e+37
0.2
83
B1u
1093
1093
1103
1103
84
B3u
1103
1112
1104
1231
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.