-    GITTINSITE     -    ZrCaSi2O7

Theoretical atomic positions and lattice parameters at experimental volum from 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:  C2 
Lattice parameters (Å):  6.8520  8.6590  4.6860 
Angles (°):  90.0  101.7  90.0 

Symmetry (theoretical): 

Space group:  C2 
Lattice parameters (Å):  5.5233  5.5233  4.6839 
Angles (°):  82.9  97.1  76.5 

Cell contents: 

Number of atoms:  11 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Zr:  0.3180  0.3180  0.5000 
Ca:  0.7057  0.7057  0.5000 
Si:  0.2041  0.7812  0.9166 
O:  0.9393  0.9393  0.0000 
O:  0.3700  0.6216  0.2167 
O:  0.3396  0.9687  0.7377 
O:  0.1216  0.5909  0.7085 
Si:  0.7812  0.2041  0.0834 
O:  0.6216  0.3700  0.7833 
O:  0.9687  0.3396  0.2623 
O:  0.5909  0.1216  0.2915 
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
A
69
88
69
86
3.435e+39
8.6
3.984e+39
10.0
7.419e+39
18.6
5
A
157
157
157
157
3.590e+37
0.1
5.839e+37
0.1
9.430e+37
0.2
6
B
157
157
158
158
2.807e+39
7.1
2.012e+39
5.1
4.819e+39
12.1
7
B
185
185
187
185
6.772e+39
17.0
2.679e+39
6.7
9.451e+39
23.8
8
A
202
203
202
203
1.632e+39
4.1
2.398e+39
6.0
4.030e+39
10.1
9
A
213
221
213
214
1.145e+39
2.9
1.475e+39
3.7
2.620e+39
6.6
10
B
246
246
264
246
7.924e+38
2.0
6.052e+38
1.5
1.398e+39
3.5
11
A
274
292
274
274
4.062e+39
10.2
4.836e+39
12.2
8.898e+39
22.4
12
A
310
310
310
312
1.322e+39
3.3
2.152e+39
5.4
3.474e+39
8.7
13
B
312
312
315
359
8.959e+38
2.3
7.584e+38
1.9
1.654e+39
4.2
14
B
359
359
359
365
2.265e+39
5.7
1.075e+39
2.7
3.339e+39
8.4
15
A
366
372
366
391
3.383e+38
0.9
5.519e+38
1.4
8.902e+38
2.2
16
B
391
391
395
391
5.887e+39
14.8
2.453e+39
6.2
8.341e+39
21.0
17
A
395
410
422
405
2.974e+39
7.5
4.951e+39
12.4
7.925e+39
19.9
18
A
425
430
425
432
4.283e+39
10.8
5.769e+39
14.5
1.005e+40
25.3
19
B
434
434
441
434
1.841e+40
46.3
8.855e+39
22.3
2.727e+40
68.5
20
A
478
496
478
478
5.863e+39
14.7
6.986e+39
17.6
1.285e+40
32.3
21
B
496
506
501
496
1.967e+39
4.9
2.592e+38
0.7
2.227e+39
5.6
22
A
508
516
508
508
7.341e+38
1.8
9.860e+38
2.5
1.720e+39
4.3
23
B
532
532
556
532
1.586e+39
4.0
6.483e+38
1.6
2.234e+39
5.6
24
B
560
560
566
560
2.213e+40
55.6
6.478e+39
16.3
2.861e+40
71.9
25
A
605
661
605
605
4.990e+39
12.5
8.419e+39
21.2
1.341e+40
33.7
26
B
664
664
673
664
4.570e+39
11.5
1.988e+38
0.5
4.769e+39
12.0
27
A
849
863
849
859
4.258e+39
10.7
4.808e+39
12.1
9.066e+39
22.8
28
B
865
865
894
865
1.830e+40
46.0
2.063e+40
51.8
3.892e+40
97.8
29
A
894
894
900
896
1.746e+40
43.9
2.233e+40
56.1
3.979e+40
100.0
30
A
900
918
911
918
3.186e+39
8.0
3.396e+39
8.5
6.582e+39
16.5
31
B
918
950
958
958
4.931e+39
12.4
4.383e+39
11.0
9.313e+39
23.4
32
B
958
958
1003
998
4.892e+39
12.3
1.393e+39
3.5
6.286e+39
15.8
33
A
1003
1072
1024
1061
7.861e+38
2.0
9.081e+38
2.3
1.694e+39
4.3
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.