-    BISMUTHINITE     -    Bi2S3

 

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:  62  Pnma 
Lattice parameters (Å):  5.9633  2.1017  5.8892 
Angles (°):  90.0  90.0  90.0 

Symmetry (theoretical): 

Space group:  62  Pnma 
Lattice parameters (Å):  11.0181  3.8455  10.6192 
Angles (°):  90  90  90 

Cell contents: 

Number of atoms:  20 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Bi:  0.5150  0.2500  0.1771 
Bi:  0.6674  0.7500  0.4741 
S:  0.6283  0.7500  0.0523 
S:  0.7179  0.2500  0.3081 
S:  0.4517  0.7500  0.3686 
Bi:  0.9850  0.7500  0.6771 
Bi:  0.8326  0.2500  0.9741 
S:  0.8717  0.2500  0.5523 
S:  0.7821  0.7500  0.8081 
S:  0.0483  0.2500  0.8686 
Bi:  0.4850  0.7500  0.8229 
Bi:  0.3326  0.2500  0.5259 
S:  0.3717  0.2500  0.9477 
S:  0.2821  0.7500  0.6919 
S:  0.5483  0.2500  0.6314 
Bi:  0.0150  0.2500  0.3229 
Bi:  0.1674  0.7500  0.0259 
S:  0.1283  0.7500  0.4477 
S:  0.2179  0.2500  0.1919 
S:  0.9517  0.7500  0.1314 
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.
 

Dielectric Properties 


We define:

  • The Born effective charges, also called dynamical charges, are tensors that correspond to the energy derivative with respect to atomic displacements and electric fields or, equivalently, to the change in atomic force due to an electric field: The sum of the Born effective charges of all nuclei in one cell must vanish, element by element, along each of the three directions of the space.
  • The dielectric tensors are the energy derivative with respect to two electric fields. They also relate the induced polarization to the external electric field.

Born effective charges (Z): 

Bi: 3.7398 -0.0000 0.2654 
-0.0000 5.5614 0.0000 
0.8258 0.0000 7.6172 
Eig. Value: 3.6645 5.5614 7.6925 
Bi: 3.9064 -0.0000 0.0164 
0.0000 7.1249 0.0000 
0.5813 -0.0000 4.3110 
Eig. Value: 3.7478 7.1249 4.4695 
S: -1.9372 0.0000 0.5442 
0.0000 -4.6871 -0.0000 
0.9799 -0.0000 -4.7213 
Eig. Value: -1.7423 -4.6871 -4.9162 
S: -3.0871 0.0000 -0.5533 
-0.0000 -3.6287 -0.0000 
-1.7748 -0.0000 -3.1295 
Eig. Value: -1.9441 -3.6287 -4.2725 
S: -2.6219 -0.0000 1.2062 
-0.0000 -4.3706 -0.0000 
0.8922 -0.0000 -4.0774 
Eig. Value: -2.0727 -4.3706 -4.6266 
Bi: 3.7398 -0.0000 -0.2654 
0.0000 5.5614 -0.0000 
-0.8258 -0.0000 7.6172 
Eig. Value: 3.6645 5.5614 7.6925 
Bi: 3.9064 -0.0000 -0.0164 
-0.0000 7.1249 0.0000 
-0.5813 0.0000 4.3110 
Eig. Value: 3.7478 7.1249 4.4695 
S: -1.9372 0.0000 -0.5442 
0.0000 -4.6871 0.0000 
-0.9799 -0.0000 -4.7213 
Eig. Value: -1.7423 -4.6871 -4.9162 
S: -3.0871 0.0000 0.5533 
-0.0000 -3.6287 0.0000 
1.7748 0.0000 -3.1295 
Eig. Value: -1.9441 -3.6287 -4.2725 
S: -2.6219 -0.0000 -1.2062 
-0.0000 -4.3706 -0.0000 
-0.8922 0.0000 -4.0774 
Eig. Value: -2.0727 -4.3706 -4.6266 
Bi: 3.7398 0.0000 0.2654 
0.0000 5.5614 -0.0000 
0.8258 -0.0000 7.6172 
Eig. Value: 3.6645 5.5614 7.6925 
Bi: 3.9064 0.0000 0.0164 
-0.0000 7.1249 0.0000 
0.5813 -0.0000 4.3110 
Eig. Value: 3.7478 7.1249 4.4695 
S: -1.9372 -0.0000 0.5442 
0.0000 -4.6871 0.0000 
0.9799 -0.0000 -4.7213 
Eig. Value: -1.7423 -4.6871 -4.9162 
S: -3.0871 -0.0000 -0.5533 
0.0000 -3.6287 0.0000 
-1.7748 0.0000 -3.1295 
Eig. Value: -1.9441 -3.6287 -4.2725 
S: -2.6219 0.0000 1.2062 
0.0000 -4.3706 -0.0000 
0.8922 -0.0000 -4.0774 
Eig. Value: -2.0727 -4.3706 -4.6266 
Bi: 3.7398 0.0000 -0.2654 
0.0000 5.5614 0.0000 
-0.8258 0.0000 7.6172 
Eig. Value: 3.6645 5.5614 7.6925 
Bi: 3.9064 0.0000 -0.0164 
0.0000 7.1249 -0.0000 
-0.5813 0.0000 4.3110 
Eig. Value: 3.7478 7.1249 4.4695 
S: -1.9372 -0.0000 -0.5442 
0.0000 -4.6871 -0.0000 
-0.9799 0.0000 -4.7213 
Eig. Value: -1.7423 -4.6871 -4.9162 
S: -3.0871 -0.0000 0.5533 
0.0000 -3.6287 -0.0000 
1.7748 -0.0000 -3.1295 
Eig. Value: -1.9441 -3.6287 -4.2725 
S: -2.6219 0.0000 -1.2062 
0.0000 -4.3706 0.0000 
-0.8922 0.0000 -4.0774 
Eig. Value: -2.0727 -4.3706 -4.6266 
Atom type 

Dielectric tensors: 

 
Ɛ14.9505 0.0000 0.0000 
0.0000 16.7657 0.0000 
0.0000 0.0000 19.3845 
Eig. Value: 14.9505 16.7657 19.3845 
Refractive index (N): 3.8666 0.0000 0.0000 
0.0000 4.0946 0.0000 
0.0000 0.0000 4.4028 
Eig. Value: 3.8666 4.0946 4.4028 
Ɛ00.0000 0.0000 0.0000 
0.0000 0.0000 0.0000 
0.0000 0.0000 0.0000 
Eig. Value: 0.0000 0.0000 0.0000