 RORISITE  CaClF
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:  129  P4/nmm  
Lattice parameters (Å):  2.0606  2.0606  3.6079  
Angles (°):  90.0  90.0  90.0 
Symmetry (theoretical):
Space group:  129  P4/nmm  
Lattice parameters (Å):  3.9019  3.9019  6.7905  
Angles (°):  90.0  90.0  90.0 
Cell contents:
Number of atoms:  6 
Number of atom types:  3 
Chemical composition:  0 
Atomic positions (theoretical):
Ca:  0.2500  0.2500  0.1952 
Cl:  0.2500  0.2500  0.6435 
F:  0.7500  0.2500  0.0000 
Ca:  0.7500  0.7500  0.8048 
Cl:  0.7500  0.7500  0.3565 
F:  0.2500  0.7500  0.0000 
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:
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 densityfunctional 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.
Choose the polarization of the lasers.
Xmin:  
Xmax: 
Ymin:  
Ymax: 
Data about the phonon modes
Frequency of the transverse (TO) and longitudinal (LO) phonon modes in the zonecenter. 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 

2  ac 

3  ac 

4  Eu 

5  Eu 

6  Eg 
9.271e+37
0.8

1.275e+38
1.1

2.202e+38
1.9


7  Eg 
9.271e+37
0.8

1.275e+38
1.1

2.202e+38
1.9


8  A2u 

9  Eg 
2.914e+38
2.5

4.007e+38
3.4

6.921e+38
5.9


10  Eg 
2.914e+38
2.5

4.007e+38
3.4

6.921e+38
5.9


11  A1g 
8.554e+39
72.6

7.704e+38
6.5

9.325e+39
79.2


12  B1g 
6.731e+39
57.1

5.048e+39
42.9

1.178e+40
100.0


13  A1g 
4.228e+39
35.9

1.507e+38
1.3

4.379e+39
37.2


14  Eu 

15  Eu 

16  A2u 

17  Eg 
2.172e+39
18.4

2.987e+39
25.4

5.159e+39
43.8


18  Eg 
2.172e+39
18.4

2.987e+39
25.4

5.159e+39
43.8

You can define the size of the supercell for the visualization of the vibration.