-    HUNTITE     -    Mg3Ca(CO3)4

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:  155  R32 
Lattice parameters (Å):  9.5027  9.5027  7.8212 
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  155  R32 
Lattice parameters (Å):  5.9877  5.9877  5.9877 
Angles (°):  103.51  103.51  103.51 

Cell contents: 

Number of atoms:  20 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Mg:  0.0000  0.0000  0.0000 
Ca:  0.5451  0.4549  0.0000 
C:  0.5000  0.5000  0.5000 
C:  0.9542  0.0458  0.5000 
O:  0.3643  0.6357  0.5000 
O:  0.0905  0.9095  0.5000 
O:  0.9743  0.1965  0.3824 
Ca:  0.4549  0.0000  0.5451 
C:  0.0458  0.5000  0.9542 
O:  0.6357  0.5000  0.3643 
O:  0.9095  0.5000  0.0905 
O:  0.1965  0.3824  0.9743 
Ca:  0.0000  0.5451  0.4549 
C:  0.5000  0.9542  0.0458 
O:  0.5000  0.3643  0.6357 
O:  0.5000  0.0905  0.9095 
O:  0.6176  0.8035  0.0257 
O:  0.3824  0.9743  0.1965 
O:  0.8035  0.0257  0.6176 
O:  0.0257  0.6176  0.8035 
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
-11
-11
-10
-8
2
ac
-8
-8
-8
-8
3
ac
-6
-6
-5
-5
4
A2
33
33
35
49
4.681e+38
0.6
7.432e+38
0.9
1.211e+39
1.5
5
E
113
113
117
113
1.601e+39
2.0
2.293e+39
2.9
3.895e+39
4.9
6
E
122
125
122
122
6.421e+38
0.8
7.919e+38
1.0
1.434e+39
1.8
7
E
147
147
148
147
8.715e+38
1.1
1.420e+39
1.8
2.291e+39
2.9
8
E
151
151
151
151
7.386e+37
0.1
9.258e+37
0.1
1.664e+38
0.2
9
A2
160
160
160
160
1.401e+39
1.8
1.860e+39
2.3
3.262e+39
4.1
10
A1
164
165
165
164
2.217e+38
0.3
2.537e+38
0.3
4.754e+38
0.6
11
E
175
175
175
175
1.083e+38
0.1
1.070e+38
0.1
2.152e+38
0.3
12
E
177
177
177
177
1.910e+38
0.2
2.099e+38
0.3
4.009e+38
0.5
13
A2
185
185
185
188
1.634e+37
0.0
2.489e+37
0.0
4.123e+37
0.1
14
A2
214
214
214
232
1.987e+37
0.0
2.866e+37
0.0
4.853e+37
0.1
15
E
233
233
234
233
4.008e+39
5.0
6.650e+39
8.4
1.066e+40
13.4
16
E
236
236
236
236
2.970e+39
3.7
3.485e+39
4.4
6.454e+39
8.1
17
E
246
246
248
247
2.276e+39
2.9
3.110e+39
3.9
5.385e+39
6.8
18
E
248
251
250
248
4.560e+39
5.7
6.266e+39
7.9
1.083e+40
13.6
19
A2
251
260
257
260
9.890e+38
1.2
9.894e+38
1.2
1.978e+39
2.5
20
E
274
275
274
274
1.507e+39
1.9
1.468e+39
1.8
2.975e+39
3.7
21
E
275
279
281
275
1.521e+39
1.9
2.439e+39
3.1
3.961e+39
5.0
22
E
292
292
292
292
2.813e+39
3.5
4.532e+39
5.7
7.345e+39
9.2
23
E
293
299
301
293
2.711e+39
3.4
3.438e+39
4.3
6.148e+39
7.7
24
A2
323
323
323
323
3.249e+38
0.4
1.760e+37
0.0
3.425e+38
0.4
25
A1
330
330
330
334
5.068e+38
0.6
5.441e+38
0.7
1.051e+39
1.3
26
E
346
346
349
347
2.794e+39
3.5
3.017e+39
3.8
5.811e+39
7.3
27
E
350
352
350
350
3.332e+39
4.2
3.579e+39
4.5
6.911e+39
8.7
28
A2
367
367
368
378
6.442e+36
0.0
1.050e+37
0.0
1.695e+37
0.0
29
E
379
379
380
380
1.254e+38
0.2
1.640e+38
0.2
2.893e+38
0.4
30
E
380
400
400
385
1.089e+38
0.1
1.606e+38
0.2
2.695e+38
0.3
31
E
411
411
411
412
2.688e+37
0.0
2.695e+37
0.0
5.383e+37
0.1
32
E
412
413
413
413
8.582e+37
0.1
1.056e+38
0.1
1.914e+38
0.2
33
A2
413
420
418
427
1.026e+38
0.1
1.154e+38
0.1
2.179e+38
0.3
34
E
427
427
429
429
2.034e+39
2.6
2.074e+39
2.6
4.107e+39
5.2
35
E
429
448
448
448
1.912e+39
2.4
2.492e+39
3.1
4.404e+39
5.5
36
A1
448
501
500
478
2.896e+38
0.4
1.212e+38
0.2
4.109e+38
0.5
37
E
704
705
704
704
1.477e+38
0.2
1.148e+38
0.1
2.625e+38
0.3
38
E
706
706
707
706
2.047e+38
0.3
3.001e+38
0.4
5.048e+38
0.6
39
A1
712
712
712
712
1.635e+36
0.0
1.357e+36
0.0
2.992e+36
0.0
40
E
724
724
725
724
1.803e+39
2.3
2.447e+39
3.1
4.250e+39
5.3
41
E
725
725
726
725
3.918e+38
0.5
2.673e+38
0.3
6.591e+38
0.8
42
A2
726
726
726
726
2.084e+39
2.6
1.557e+39
2.0
3.641e+39
4.6
43
E
727
728
727
727
8.377e+37
0.1
8.536e+37
0.1
1.691e+38
0.2
44
E
728
728
728
728
4.979e+38
0.6
7.589e+38
1.0
1.257e+39
1.6
45
A2
825
825
825
844
1.000e+37
0.0
1.679e+37
0.0
2.679e+37
0.0
46
E
845
845
845
846
1.102e+39
1.4
1.204e+39
1.5
2.306e+39
2.9
47
E
847
847
847
849
1.097e+39
1.4
1.842e+39
2.3
2.939e+39
3.7
48
A2
878
878
878
890
49
A1
1114
1114
1114
1114
2.239e+39
2.8
1.160e+38
0.1
2.355e+39
3.0
50
E
1127
1127
1127
1127
3.459e+38
0.4
7.278e+37
0.1
4.186e+38
0.5
51
E
1128
1128
1128
1128
7.429e+37
0.1
1.213e+38
0.2
1.956e+38
0.2
52
A1
1134
1134
1134
1134
7.766e+40
97.6
1.881e+39
2.4
7.954e+40
100.0
53
E
1463
1464
1463
1463
2.255e+38
0.3
1.717e+38
0.2
3.972e+38
0.5
54
E
1464
1476
1476
1464
1.997e+38
0.3
2.530e+38
0.3
4.526e+38
0.6
55
E
1484
1484
1485
1484
8.818e+38
1.1
1.232e+39
1.5
2.114e+39
2.7
56
E
1485
1504
1504
1485
8.711e+38
1.1
6.538e+38
0.8
1.525e+39
1.9
57
A1
1504
1514
1514
1506
5.424e+35
0.0
6.491e+35
0.0
1.191e+36
0.0
58
A2
1518
1518
1518
1518
2.074e+38
0.3
1.186e+38
0.1
3.259e+38
0.4
59
E
1522
1522
1522
1522
1.878e+38
0.2
1.489e+38
0.2
3.367e+38
0.4
60
E
1522
1628
1628
1522
1.959e+38
0.2
3.028e+38
0.4
4.987e+38
0.6
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.