-    KIESERITE     -    MgSO4H2O

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:  15  C2/c 
Lattice parameters (Å):  6.8910  7.6240  7.6450 
Angles (°):  90.0  117.7  90.0 

Symmetry (theoretical): 

Space group:  15  C2/c 
Lattice parameters (Å):  5.0717  5.0717  7.3483 
Angles (°):  73.2  106.8  80.9 

Cell contents: 

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

Atomic positions (theoretical):

Mg:  0.5000  0.5000  0.0000 
S:  0.1626  0.1626  0.2500 
O:  0.2299  0.8818  0.4044 
O:  0.3850  0.1655  0.1558 
O:  0.6290  0.6290  0.2500 
H:  0.8440  0.5658  0.2952 
Mg:  0.5000  0.5000  0.5000 
O:  0.8818  0.2299  0.0956 
O:  0.1655  0.3850  0.3442 
H:  0.5658  0.8440  0.2048 
S:  0.8374  0.8374  0.7500 
O:  0.7701  0.1182  0.5956 
O:  0.6150  0.8345  0.8442 
O:  0.3710  0.3710  0.7500 
H:  0.1560  0.4342  0.7048 
O:  0.1182  0.7701  0.9044 
O:  0.8345  0.6150  0.6558 
H:  0.4342  0.1560  0.7952 
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.

Choose the polarization of the lasers.

I ∥ 
I ⊥ 
I Total 
Horizontal:
Xmin:
Xmax:
Vertical:
Ymin:
Ymax:
 

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-u
0
0
0
0
2
Ac-u
0
0
0
0
3
Ac-u
0
0
0
0
4
Bg
69
69
69
69
1.792e+38
0.1
2.282e+38
0.1
4.074e+38
0.2
5
Bu
118
118
118
119
6
Bg
123
123
123
123
5.005e+37
0.0
8.247e+37
0.0
1.325e+38
0.1
7
Au
128
128
130
128
8
Ag
146
146
146
146
1.636e+39
0.9
1.598e+39
0.9
3.235e+39
1.8
9
Bu
202
208
202
215
10
Bg
215
215
215
216
1.460e+39
0.8
2.123e+39
1.2
3.582e+39
2.0
11
Bu
227
227
227
232
12
Bg
241
241
241
241
1.625e+39
0.9
1.815e+39
1.0
3.440e+39
1.9
13
Ag
242
242
242
242
1.596e+40
8.9
4.810e+38
0.3
1.644e+40
9.2
14
Au
243
243
246
243
15
Ag
294
294
294
294
4.349e+39
2.4
8.481e+38
0.5
5.197e+39
2.9
16
Bg
305
305
305
305
1.545e+39
0.9
2.240e+39
1.3
3.785e+39
2.1
17
Bu
308
328
308
314
18
Au
328
332
338
328
19
Bu
338
343
349
352
20
Bg
366
366
366
366
7.486e+38
0.4
1.131e+39
0.6
1.879e+39
1.0
21
Au
383
383
387
383
22
Bu
387
409
393
391
23
Au
410
410
413
410
24
Bu
413
417
417
417
25
Ag
417
429
427
430
1.025e+40
5.7
6.681e+39
3.7
1.693e+40
9.5
26
Au
430
430
455
443
27
Ag
513
513
513
513
7.882e+39
4.4
6.604e+39
3.7
1.449e+40
8.1
28
Au
547
547
552
547
29
Bu
600
605
600
605
30
Bg
605
606
605
611
7.728e+39
4.3
1.270e+40
7.1
2.043e+40
11.4
31
Bg
616
616
616
616
3.603e+39
2.0
3.849e+39
2.2
7.452e+39
4.2
32
Ag
619
619
619
619
9.381e+39
5.2
4.856e+39
2.7
1.424e+40
8.0
33
Bu
622
625
622
623
34
Au
625
673
633
625
35
Bg
776
776
776
776
4.819e+38
0.3
5.533e+38
0.3
1.035e+39
0.6
36
Bu
782
801
782
800
37
Bu
963
1000
963
999
38
Au
1000
1004
1004
1000
39
Ag
1004
1020
1005
1004
1.172e+41
65.5
6.578e+38
0.4
1.179e+41
65.9
40
Bg
1020
1024
1020
1020
1.607e+39
0.9
2.086e+39
1.2
3.693e+39
2.1
41
Au
1024
1044
1027
1024
42
Ag
1044
1046
1044
1044
1.201e+40
6.7
2.010e+39
1.1
1.403e+40
7.8
43
Bg
1074
1074
1074
1074
3.870e+39
2.2
6.480e+39
3.6
1.035e+40
5.8
44
Bu
1105
1120
1105
1110
45
Ag
1120
1127
1120
1120
1.686e+40
9.4
6.044e+39
3.4
2.290e+40
12.8
46
Au
1146
1146
1201
1146
47
Bu
1201
1234
1216
1234
48
Bg
1234
1246
1234
1269
4.986e+39
2.8
5.331e+39
3.0
1.032e+40
5.8
49
Ag
1527
1527
1527
1527
3.396e+39
1.9
2.766e+39
1.5
6.162e+39
3.4
50
Au
1543
1543
1549
1543
51
Bu
2914
2919
2914
2919
52
Bg
2919
2966
2919
2919
1.560e+40
8.7
1.977e+40
11.0
3.537e+40
19.8
53
Ag
2966
2994
2966
2966
1.494e+41
83.5
2.961e+40
16.5
1.790e+41
100.0
54
Au
2994
3050
3014
2994
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.