-    SCOTLANDITE     -    PbSO3

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. Tetter norm-conserving pseudopotential for Pb. 

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:  11  P2_1/m 
Lattice parameters (Å):  4.5050  5.3330  6.4050 
Angles (°):  90  106.24  90 

Symmetry (theoretical): 

Space group:  11  P2_1/m 
Lattice parameters (Å):  4.4136  5.2571  6.2065 
Angles (°):  90  105.49  90 

Cell contents: 

Number of atoms:  10 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Pb:  0.6503  0.2500  0.2766 
S:  0.0868  0.7500  0.1693 
O:  0.7300  0.7500  0.1305 
O:  0.1981  0.5218  0.3236 
Pb:  0.3497  0.7500  0.7234 
S:  0.9132  0.2500  0.8307 
O:  0.2700  0.2500  0.8695 
O:  0.8019  0.0218  0.6764 
O:  0.8019  0.4782  0.6764 
O:  0.1981  0.9782  0.3236 
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.

Choose the polarization of the lasers.

I ∥ 
I ⊥ 
I Total 
Horizontal:
Xmin:
Xmax:
Vertical:
Ymin:
Ymax:
 

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
Ag
55
55
55
55
9.012e+40
19.4
6.240e+40
13.4
1.525e+41
32.8
5
Bg
56
56
56
56
1.440e+40
3.1
2.232e+40
4.8
3.672e+40
7.9
6
Ag
70
70
70
70
4.146e+40
8.9
1.959e+40
4.2
6.105e+40
13.1
7
Au
75
75
90
75
8
Bg
90
90
99
90
2.347e+40
5.1
3.003e+40
6.5
5.350e+40
11.5
9
Bu
99
100
103
102
10
Bu
103
124
124
124
11
Ag
124
147
143
147
2.571e+40
5.5
2.703e+40
5.8
5.274e+40
11.4
12
Au
147
148
148
148
13
Bg
148
150
150
150
3.734e+39
0.8
6.199e+39
1.3
9.933e+39
2.1
14
Ag
150
174
168
174
3.830e+40
8.2
7.842e+39
1.7
4.614e+40
9.9
15
Au
174
188
201
201
16
Ag
201
201
203
203
3.113e+40
6.7
6.881e+39
1.5
3.801e+40
8.2
17
Bg
203
203
216
208
4.076e+40
8.8
4.832e+40
10.4
8.908e+40
19.2
18
Bu
219
250
219
219
19
Bg
455
455
455
455
5.812e+40
12.5
9.593e+40
20.6
1.541e+41
33.2
20
Ag
458
458
458
458
5.608e+40
12.1
4.586e+40
9.9
1.019e+41
21.9
21
Au
459
459
470
459
22
Bu
476
482
476
486
23
Bu
608
608
608
608
24
Ag
608
613
608
624
2.205e+40
4.7
2.655e+39
0.6
2.470e+40
5.3
25
Au
851
851
877
851
26
Bg
877
877
879
877
1.361e+40
2.9
2.006e+40
4.3
3.367e+40
7.2
27
Ag
879
879
882
879
8.678e+40
18.7
5.959e+40
12.8
1.464e+41
31.5
28
Bu
882
918
918
895
29
Bu
918
928
928
928
30
Ag
928
961
953
950
2.847e+41
61.3
1.799e+41
38.7
4.647e+41
100.0
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.