-    ZIRCON     -    ZrSiO4

 

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:  141  I4_1/amd 
Lattice parameters (Å):  6.8947  6.8947  6.0276 
Angles (°):  90  90  90 

Symmetry (theoretical): 

Space group:  141  I4_1/amd 
Lattice parameters (Å):  5.4902  5.4902  5.4902 
Angles (°):  106.83  106.83  114.87 

Cell contents: 

Number of atoms:  12 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Zr:  0.0000  0.0000  0.0000 
Si:  0.5000  0.5000  0.0000 
O:  0.5040  0.3199  0.1841 
O:  0.1358  0.3199  0.8159 
Zr:  0.7500  0.2500  0.5000 
Si:  0.2500  0.7500  0.5000 
O:  0.0699  0.3858  0.3159 
O:  0.0699  0.7540  0.6841 
O:  0.6142  0.9301  0.6841 
O:  0.2460  0.9301  0.3159 
O:  0.6801  0.4960  0.8159 
O:  0.6801  0.8642  0.1841 
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
B1u
127
127
127
127
5
Eg
194
194
194
194
4.241e+39
1.9
5.896e+39
2.7
1.014e+40
4.6
6
Eg
194
194
194
194
4.241e+39
1.9
5.766e+39
2.6
1.001e+40
4.6
7
B1g
223
223
223
223
8.259e+39
3.8
6.194e+39
2.8
1.445e+40
6.6
8
Eg
225
225
225
225
8.033e+39
3.7
1.339e+40
6.1
2.142e+40
9.8
9
Eg
225
225
225
225
8.033e+39
3.7
8.704e+39
4.0
1.674e+40
7.6
10
A2g
242
242
242
242
11
B2g
257
257
257
257
9.746e+38
0.4
1.340e+39
0.6
2.315e+39
1.1
12
Eu
281
281
281
281
13
Eu
281
339
339
281
14
A2u
343
343
343
364
15
Eg
364
364
364
364
3.797e+40
17.3
5.378e+40
24.5
9.175e+40
41.8
16
Eg
364
364
364
376
3.797e+40
17.3
5.064e+40
23.1
8.861e+40
40.4
17
Eu
376
376
376
376
18
Eu
376
390
390
390
19
B1g
390
392
392
392
3.257e+39
1.5
2.442e+39
1.1
5.699e+39
2.6
20
A1u
392
417
417
423
21
Eu
423
423
423
423
22
Eu
423
438
438
438
23
A1g
438
465
465
473
8.276e+40
37.7
3.679e+40
16.8
1.196e+41
54.5
24
Eg
536
536
536
536
1.434e+37
0.0
2.296e+37
0.0
3.730e+37
0.0
25
Eg
536
536
536
536
1.434e+37
0.0
1.647e+37
0.0
3.081e+37
0.0
26
B2u
562
562
562
562
27
A2u
597
597
597
627
28
B1g
627
627
627
640
8.416e+38
0.4
6.312e+38
0.3
1.473e+39
0.7
29
Eu
866
866
866
866
30
Eu
866
920
920
866
31
Eg
920
920
920
920
2.402e+37
0.0
2.563e+37
0.0
4.965e+37
0.0
32
Eg
920
937
937
920
2.402e+37
0.0
4.042e+37
0.0
6.444e+37
0.0
33
B2u
937
966
966
937
34
A1g
966
976
976
966
2.585e+40
11.8
2.348e+39
1.1
2.820e+40
12.9
35
A2u
976
1012
1012
1012
36
B1g
1012
1026
1026
1094
1.253e+41
57.1
9.400e+40
42.9
2.193e+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.