-    HERZENBERGITE     -    SnS

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:  62  Pbnm 
Lattice parameters (Å):  4.7104  10.2718  8.7476 
Angles (°):  90  90  90 

Symmetry (theoretical): 

Space group:  62  Pbnm 
Lattice parameters (Å):  4.0445  10.3365  3.7834 
Angles (°):  90  90  90 

Cell contents: 

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

Atomic positions (theoretical):

Sn:  0.1176  0.1119  0.2500 
S:  0.4555  0.8577  0.2500 
Sn:  0.6176  0.3881  0.7500 
S:  0.9555  0.6423  0.7500 
Sn:  0.8824  0.8881  0.7500 
S:  0.5445  0.1423  0.7500 
Sn:  0.3824  0.6119  0.2500 
S:  0.0445  0.3577  0.2500 
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
A1g
46
46
46
46
6.914e+42
7.0
2.115e+42
2.1
9.029e+42
9.1
5
Au
59
59
59
59
6
B2g
64
64
64
64
5.495e+41
0.6
7.555e+41
0.8
1.305e+42
1.3
7
B2u
68
68
69
68
8
B3g
87
87
87
87
2.873e+42
2.9
3.950e+42
4.0
6.823e+42
6.9
9
B1g
91
91
91
91
1.337e+41
0.1
1.838e+41
0.2
3.175e+41
0.3
10
B1g
112
112
112
112
1.425e+39
0.0
1.960e+39
0.0
3.386e+39
0.0
11
A1g
114
114
114
114
5.633e+42
5.7
4.201e+42
4.2
9.835e+42
9.9
12
B3u
126
128
126
126
13
B1u
169
169
169
191
14
B2u
191
191
201
201
15
B2g
201
201
207
207
4.174e+43
42.1
5.739e+43
57.9
9.913e+43
100.0
16
B3u
207
227
227
227
17
A1g
227
227
227
227
8.641e+43
87.2
5.790e+42
5.8
9.220e+43
93.0
18
Au
227
237
237
237
19
B3g
237
243
242
243
2.108e+40
0.0
2.898e+40
0.0
5.006e+40
0.1
20
B2u
243
259
266
266
21
B3u
266
273
273
273
22
A1g
273
276
276
276
1.420e+43
14.3
9.928e+41
1.0
1.519e+43
15.3
23
B1g
276
297
297
285
1.288e+42
1.3
1.771e+42
1.8
3.059e+42
3.1
24
B1g
297
310
375
297
8.446e+41
0.9
1.161e+42
1.2
2.006e+42
2.0
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.