-    ARAGONITE     -    CaCO3

Theoretical atomic positions. Lattice parameters fixed as in RRUFF entry #R060195 

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):  4.9608  7.9688  5.7411 
Angles (°):  90.0  90.0  90.0 

Symmetry (theoretical): 

Space group:  62  Pnma 
Lattice parameters (Å):  4.9608  7.9688  5.7411 
Angles (°):  90.0  90.0  90.0 

Cell contents: 

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

Atomic positions (theoretical):

Ca:  0.2500  0.5494  0.2505 
C:  0.2500  0.7640  0.8841 
O:  0.2500  0.9247  0.8686 
O:  0.4751  0.6870  0.9006 
Ca:  0.7500  0.9506  0.7505 
C:  0.7500  0.7360  0.3841 
O:  0.7500  0.5753  0.3686 
O:  0.5249  0.8130  0.4006 
Ca:  0.7500  0.4506  0.7495 
C:  0.7500  0.2360  0.1159 
O:  0.7500  0.0753  0.1314 
O:  0.9751  0.3130  0.0994 
Ca:  0.2500  0.0494  0.2495 
C:  0.2500  0.2640  0.6159 
O:  0.2500  0.4247  0.6314 
O:  0.0249  0.1870  0.5994 
O:  0.5249  0.3130  0.0994 
O:  0.4751  0.1870  0.5994 
O:  0.0249  0.6870  0.9006 
O:  0.9751  0.8130  0.4006 
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
A1u
25
25
25
25
5
A2g
43
43
43
43
1.630e+39
1.6
2.241e+39
2.2
3.871e+39
3.7
6
A1u
94
94
94
94
7
A1g
110
110
110
110
7.445e+38
0.7
3.809e+38
0.4
1.125e+39
1.1
8
B1u
115
115
122
115
9
B2u
124
126
124
124
10
B1g
126
127
126
126
4.215e+38
0.4
5.795e+38
0.6
1.001e+39
1.0
11
A2g
134
134
134
134
1.043e+39
1.0
1.434e+39
1.4
2.477e+39
2.4
12
A1u
149
149
149
149
13
B1g
155
155
155
155
4.072e+39
3.9
5.599e+39
5.4
9.671e+39
9.4
14
A2u
167
167
167
172
15
A1g
172
172
172
172
4.550e+39
4.4
1.671e+39
1.6
6.221e+39
6.0
16
A1u
172
172
172
173
17
A2g
173
173
173
175
4.981e+39
4.8
6.849e+39
6.6
1.183e+40
11.5
18
B2g
175
175
175
178
8.266e+36
0.0
1.137e+37
0.0
1.963e+37
0.0
19
A1g
178
178
178
181
1.737e+39
1.7
5.559e+38
0.5
2.293e+39
2.2
20
B1g
181
181
181
188
5.157e+39
5.0
7.090e+39
6.9
1.225e+40
11.9
21
B2u
191
198
191
191
22
B1u
198
220
220
198
23
A2u
220
223
223
223
24
A2g
223
227
227
227
1.541e+37
0.0
2.118e+37
0.0
3.659e+37
0.0
25
B2g
227
228
228
228
1.801e+39
1.7
2.477e+39
2.4
4.278e+39
4.1
26
A1g
228
239
228
239
3.818e+39
3.7
1.401e+39
1.4
5.219e+39
5.1
27
B2g
239
241
239
241
7.248e+39
7.0
9.966e+39
9.7
1.721e+40
16.7
28
B2g
241
244
241
243
1.023e+39
1.0
1.406e+39
1.4
2.429e+39
2.4
29
A2u
244
249
244
249
30
B1g
249
251
249
251
1.053e+40
10.2
1.447e+40
14.0
2.500e+40
24.2
31
B2u
251
255
251
255
32
B1u
255
278
266
278
33
B1u
278
283
283
279
34
A1g
283
292
292
283
2.059e+39
2.0
9.415e+38
0.9
3.001e+39
2.9
35
B2g
292
315
329
292
6.804e+39
6.6
9.355e+39
9.1
1.616e+40
15.7
36
A2u
329
329
352
387
37
B2g
674
674
674
674
8.935e+37
0.1
1.229e+38
0.1
2.122e+38
0.2
38
A2u
677
677
677
677
39
A1g
682
682
682
682
5.596e+39
5.4
3.875e+39
3.8
9.471e+39
9.2
40
B1u
688
688
690
688
41
B2u
696
698
696
696
42
A1u
699
699
699
699
43
A2g
701
701
701
701
2.065e+39
2.0
2.840e+39
2.8
4.905e+39
4.8
44
B1g
702
702
702
702
4.406e+38
0.4
6.059e+38
0.6
1.047e+39
1.0
45
A1g
855
855
855
855
1.224e+39
1.2
2.817e+38
0.3
1.505e+39
1.5
46
A2u
856
856
856
861
47
B1u
861
861
861
862
48
B2g
862
862
862
869
1.714e+38
0.2
2.357e+38
0.2
4.071e+38
0.4
49
B1u
1083
1083
1083
1083
50
B2g
1084
1084
1084
1084
1.162e+37
0.0
1.598e+37
0.0
2.761e+37
0.0
51
A1g
1084
1084
1084
1084
1.003e+41
97.1
2.956e+39
2.9
1.032e+41
100.0
52
A2u
1085
1085
1085
1085
53
B2u
1402
1421
1402
1402
54
B1g
1421
1423
1421
1421
3.376e+39
3.3
4.642e+39
4.5
8.018e+39
7.8
55
B1u
1423
1430
1430
1423
56
A1g
1430
1454
1454
1430
6.583e+38
0.6
6.264e+36
0.0
6.645e+38
0.6
57
A2u
1454
1458
1458
1454
58
A1u
1458
1476
1476
1458
59
A2g
1476
1538
1538
1476
2.191e+39
2.1
3.013e+39
2.9
5.204e+39
5.0
60
B2g
1538
1542
1547
1538
4.224e+38
0.4
5.808e+38
0.6
1.003e+39
1.0
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.