-    COLQUIRIITE     -    LiCaAlF6

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:  163  P-31c 
Lattice parameters (Å):  4.9960  4.9960  9.6360 
Angles (°):  90.0  90.0  120.0 

Symmetry (theoretical): 

Space group:  163  P-31c 
Lattice parameters (Å):  4.8959  4.8959  9.6254 
Angles (°):  90.0  90.0  120.0 

Cell contents: 

Number of atoms:  18 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Ca:  0.0000  0.0000  0.0000 
Li:  0.3333  0.6667  0.2500 
Al:  0.6667  0.3333  0.2500 
F:  0.3784  0.0255  0.1447 
F:  0.6471  0.6216  0.1447 
Ca:  0.0000  0.0000  0.5000 
Li:  0.6667  0.3333  0.7500 
Al:  0.3333  0.6667  0.7500 
F:  0.0255  0.3784  0.6447 
F:  0.9745  0.3529  0.1447 
F:  0.3529  0.9745  0.6447 
F:  0.6216  0.6471  0.6447 
F:  0.6216  0.9745  0.8553 
F:  0.3529  0.3784  0.8553 
F:  0.9745  0.6216  0.3553 
F:  0.0255  0.6471  0.8553 
F:  0.6471  0.0255  0.3553 
F:  0.3784  0.3529  0.3553 
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
Eg
102
102
102
102
9.231e+36
0.1
9.931e+36
0.1
1.916e+37
0.2
5
Eg
102
102
102
102
9.232e+36
0.1
1.064e+37
0.1
1.987e+37
0.2
6
Eu
120
120
120
120
7
Eu
120
123
123
120
8
A2g
123
125
125
123
9
A2u
125
126
126
156
10
Eg
163
163
163
163
1.732e+38
1.7
2.173e+38
2.1
3.905e+38
3.8
11
Eg
163
163
163
163
1.732e+38
1.7
2.451e+38
2.4
4.182e+38
4.0
12
Eu
191
191
191
191
13
Eu
191
206
206
191
14
Eu
207
207
207
207
15
Eu
207
208
208
207
16
A1u
236
236
236
236
17
Eg
255
255
255
255
18
Eg
255
255
255
255
19
A2g
257
257
257
257
20
A1g
269
269
269
269
1.637e+39
15.7
3.318e+36
0.0
1.640e+39
15.8
21
A1u
283
283
283
283
22
A2u
285
285
285
285
23
Eu
297
297
297
297
24
Eu
297
300
300
297
25
A2g
300
302
302
300
26
Eu
320
320
320
320
27
Eu
320
326
326
320
28
Eg
326
326
326
326
4.308e+38
4.1
7.115e+38
6.8
1.142e+39
11.0
29
Eg
326
334
334
326
4.308e+38
4.1
5.206e+38
5.0
9.514e+38
9.1
30
A2u
348
348
348
383
31
A1g
383
383
383
392
1.304e+39
12.5
7.309e+37
0.7
1.378e+39
13.2
32
Eg
392
392
392
392
1.180e+38
1.1
1.430e+38
1.4
2.610e+38
2.5
33
Eg
392
392
392
401
1.180e+38
1.1
9.868e+37
0.9
2.167e+38
2.1
34
Eu
401
401
401
401
35
Eu
401
413
413
401
36
A1u
413
417
417
413
37
A2g
418
418
418
418
38
A2u
428
428
428
428
39
Eg
435
435
435
435
6.148e+38
5.9
5.917e+38
5.7
1.206e+39
11.6
40
Eg
435
435
435
435
6.148e+38
5.9
9.780e+38
9.4
1.593e+39
15.3
41
Eu
441
441
441
441
42
Eu
441
457
457
441
43
Eg
457
457
457
457
1.064e+38
1.0
9.228e+37
0.9
1.987e+38
1.9
44
Eg
457
466
466
457
1.065e+38
1.0
1.518e+38
1.5
2.583e+38
2.5
45
Eu
473
473
473
473
46
Eu
473
505
505
473
47
A1g
570
570
570
570
1.040e+40
100.0
3.459e+36
0.0
1.041e+40
100.0
48
Eu
585
585
585
585
49
Eu
585
586
586
585
50
Eg
586
586
586
586
4.720e+38
4.5
5.532e+38
5.3
1.025e+39
9.9
51
Eg
586
594
594
586
4.720e+38
4.5
7.889e+38
7.6
1.261e+39
12.1
52
A1u
594
594
594
594
53
A2u
594
693
693
709
54
A2g
709
709
709
717
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.