-    GROSSITE     -    CaAl4O7

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):  6.7945  4.6898  2.8740 
Angles (°):  90  106.83  90 

Symmetry (theoretical): 

Space group:  15  C2/c 
Lattice parameters (Å):  7.8215  7.8215  5.4351 
Angles (°):  75.52  104.47  111.01 

Cell contents: 

Number of atoms:  24 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Ca:  0.8175  0.8175  0.2500 
Al:  0.2519  0.9216  0.2977 
Al:  0.5611  0.3227  0.2440 
O:  0.5317  0.5317  0.2500 
O:  0.1575  0.9278  0.5494 
O:  0.3767  0.1372  0.1567 
O:  0.6394  0.2545  0.5824 
Al:  0.9216  0.2519  0.2023 
Al:  0.3227  0.5611  0.2560 
O:  0.9278  0.1575  0.9506 
O:  0.1372  0.3767  0.3433 
O:  0.2545  0.6394  0.9176 
Ca:  0.1825  0.1825  0.7500 
Al:  0.7481  0.0784  0.7023 
Al:  0.4389  0.6773  0.7560 
O:  0.4683  0.4683  0.7500 
O:  0.8425  0.0722  0.4506 
O:  0.6233  0.8628  0.8433 
O:  0.3606  0.7455  0.4176 
Al:  0.0784  0.7481  0.7977 
Al:  0.6773  0.4389  0.7440 
O:  0.0722  0.8425  0.0494 
O:  0.8628  0.6233  0.6567 
O:  0.7455  0.3606  0.0824 
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
Bg
116
116
116
116
6.371e+37
0.3
6.792e+37
0.4
1.316e+38
0.7
5
Ag
118
118
118
118
1.576e+39
8.3
4.976e+38
2.6
2.074e+39
10.9
6
Bu
121
125
121
138
7
Ag
138
138
138
145
1.450e+39
7.6
1.124e+39
5.9
2.574e+39
13.5
8
Bu
146
151
146
164
9
Bg
164
164
164
175
7.411e+36
0.0
1.019e+37
0.1
1.760e+37
0.1
10
Au
177
177
183
177
11
Bu
183
184
184
184
12
Ag
184
184
184
184
6.270e+38
3.3
1.142e+38
0.6
7.412e+38
3.9
13
Bg
184
191
188
192
2.803e+38
1.5
3.106e+38
1.6
5.910e+38
3.1
14
Ag
199
199
199
199
1.032e+39
5.4
1.815e+38
1.0
1.213e+39
6.4
15
Au
203
203
204
203
16
Bg
204
204
213
204
4.204e+38
2.2
7.078e+38
3.7
1.128e+39
5.9
17
Bu
213
214
214
214
18
Bg
214
215
222
231
5.515e+38
2.9
6.947e+38
3.6
1.246e+39
6.5
19
Ag
247
247
247
247
8.057e+39
42.3
4.476e+38
2.4
8.504e+39
44.7
20
Bu
249
250
249
253
21
Au
253
253
253
254
22
Bg
258
258
258
258
8.222e+37
0.4
1.131e+38
0.6
1.953e+38
1.0
23
Ag
273
273
273
273
3.956e+38
2.1
4.309e+38
2.3
8.265e+38
4.3
24
Bu
276
295
276
279
25
Ag
304
304
304
304
1.329e+39
7.0
1.054e+38
0.6
1.435e+39
7.5
26
Au
307
307
312
307
27
Bg
314
314
314
314
2.913e+37
0.2
4.744e+37
0.2
7.657e+37
0.4
28
Au
315
315
315
315
29
Bu
323
331
323
323
30
Bg
343
343
343
343
1.580e+37
0.1
2.658e+37
0.1
4.238e+37
0.2
31
Ag
344
344
344
344
1.504e+39
7.9
3.039e+38
1.6
1.808e+39
9.5
32
Bu
352
354
352
354
33
Au
354
358
356
356
34
Au
378
378
378
378
35
Ag
394
394
394
394
1.874e+40
98.4
2.999e+38
1.6
1.904e+40
100.0
36
Bg
398
398
398
398
1.427e+38
0.7
1.962e+38
1.0
3.388e+38
1.8
37
Bu
409
409
409
413
38
Bg
413
413
413
413
7.972e+37
0.4
8.509e+37
0.4
1.648e+38
0.9
39
Bu
417
426
417
431
40
Au
431
431
438
439
41
Bg
439
439
439
440
7.539e+36
0.0
8.347e+36
0.0
1.589e+37
0.1
42
Ag
443
443
443
443
5.604e+39
29.4
4.531e+38
2.4
6.057e+39
31.8
43
Au
511
511
539
511
44
Bu
541
549
541
549
45
Ag
549
550
549
550
2.592e+38
1.4
2.269e+38
1.2
4.861e+38
2.6
46
Bg
550
564
550
552
8.182e+36
0.0
8.902e+36
0.0
1.708e+37
0.1
47
Au
571
571
573
571
48
Bg
606
606
606
606
2.182e+38
1.1
3.636e+38
1.9
5.818e+38
3.1
49
Bu
614
623
614
619
50
Ag
627
627
627
627
4.063e+38
2.1
3.256e+38
1.7
7.319e+38
3.8
51
Au
629
629
638
629
52
Ag
638
638
639
638
5.792e+39
30.4
1.748e+39
9.2
7.540e+39
39.6
53
Bu
640
640
640
643
54
Bg
643
643
643
661
2.422e+37
0.1
3.330e+37
0.2
5.752e+37
0.3
55
Ag
661
661
661
665
1.137e+40
59.7
3.788e+38
2.0
1.175e+40
61.7
56
Au
665
665
665
690
57
Bg
690
690
690
698
7.461e+38
3.9
1.122e+39
5.9
1.868e+39
9.8
58
Au
712
712
715
712
59
Au
716
716
728
716
60
Bg
732
732
732
732
1.572e+39
8.3
2.601e+39
13.7
4.173e+39
21.9
61
Bu
734
768
734
736
62
Ag
768
784
768
768
1.840e+39
9.7
2.361e+39
12.4
4.201e+39
22.1
63
Bg
784
789
784
784
4.519e+38
2.4
6.726e+38
3.5
1.125e+39
5.9
64
Bu
795
795
795
795
65
Ag
795
823
795
832
1.038e+39
5.4
1.195e+39
6.3
2.233e+39
11.7
66
Au
833
833
833
833
67
Au
833
838
838
838
68
Bg
838
885
844
885
1.241e+38
0.7
1.365e+38
0.7
2.606e+38
1.4
69
Au
885
887
887
887
70
Bg
887
893
926
896
1.021e+39
5.4
1.303e+39
6.8
2.324e+39
12.2
71
Bu
926
926
928
928
72
Ag
928
928
988
932
8.506e+38
4.5
8.092e+38
4.2
1.660e+39
8.7
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.