-    PLAGIOCLASE     -    (Na,Ca)(Si,Al)4O8

LABRADORITE - Theoretical structure, term in the plagioclase series treated as ideal solid solution using alchemical pseudopotentials. 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:  P-1 
Lattice parameters (Å):  7.599  7.533  6.081 
Angles (°):  106.12  101.66  114.92 

Symmetry (theoretical): 

Space group:  P-1 
Lattice parameters (Å):  7.6471  7.4941  7.0250 
Angles (°):    105.5  101.9 

Cell contents: 

Number of atoms:  26 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Na:  0.2513  0.2807  0.1133 
Si:  0.8375  0.1723  0.2196 
Si:  0.1880  0.8234  0.2286 
Si:  0.5692  0.7966  0.3253 
Si:  0.8082  0.5726  0.3532 
O:  0.8669  0.1282  0.9871 
O:  0.5930  0.5808  0.2794 
O:  0.6954  0.9275  0.1989 
O:  0.9590  0.6857  0.2349 
O:  0.7333  0.3183  0.2783 
O:  0.3174  0.6943  0.2204 
O:  0.0785  0.2945  0.3867 
O:  0.3316  0.0605  0.4209 
Na:  0.7487  0.7193  0.8867 
Si:  0.1625  0.8277  0.7804 
Si:  0.8120  0.1766  0.7714 
Si:  0.4308  0.2034  0.6747 
Si:  0.1918  0.4274  0.6468 
O:  0.1331  0.8718  0.0129 
O:  0.4070  0.4192  0.7206 
O:  0.3046  0.0725  0.8011 
O:  0.0410  0.3143  0.7651 
O:  0.2667  0.6817  0.7217 
O:  0.6826  0.3057  0.7796 
O:  0.9215  0.7055  0.6133 
O:  0.6684  0.9395  0.5791 
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
64
64
64
64
6.841e+38
2.0
6.815e+38
2.0
1.366e+39
4.0
5
Ag
69
69
69
69
1.197e+39
3.5
7.639e+38
2.2
1.961e+39
5.7
6
Au
72
77
82
79
7
Ag
93
93
93
93
1.142e+39
3.3
2.458e+38
0.7
1.388e+39
4.0
8
Au
108
111
117
116
9
Ag
119
119
119
119
4.686e+38
1.4
6.872e+38
2.0
1.156e+39
3.4
10
Ag
137
137
137
137
5.314e+38
1.5
4.918e+38
1.4
1.023e+39
3.0
11
Au
149
149
153
151
12
Au
157
158
161
159
13
Ag
162
162
162
162
9.627e+38
2.8
5.330e+38
1.6
1.496e+39
4.4
14
Ag
165
165
165
165
9.816e+38
2.9
5.890e+38
1.7
1.571e+39
4.6
15
Ag
182
182
182
182
2.466e+39
7.2
1.011e+39
2.9
3.477e+39
10.1
16
Ag
192
192
192
192
4.693e+39
13.7
3.136e+38
0.9
5.007e+39
14.6
17
Au
207
208
208
211
18
Ag
211
211
211
212
4.987e+38
1.5
4.201e+38
1.2
9.188e+38
2.7
19
Au
215
217
219
217
20
Au
224
229
225
226
21
Ag
229
232
229
229
1.445e+38
0.4
2.015e+38
0.6
3.460e+38
1.0
22
Au
246
247
246
246
23
Ag
256
256
256
256
2.126e+38
0.6
4.451e+37
0.1
2.571e+38
0.7
24
Au
266
266
266
266
25
Ag
276
276
276
276
9.881e+39
28.8
3.488e+38
1.0
1.023e+40
29.8
26
Au
280
281
280
280
27
Ag
291
291
291
291
4.389e+38
1.3
6.743e+37
0.2
5.064e+38
1.5
28
Au
305
305
305
305
29
Ag
307
307
307
307
9.870e+37
0.3
1.040e+38
0.3
2.027e+38
0.6
30
Au
326
327
329
326
31
Ag
329
329
330
329
2.553e+38
0.7
5.398e+37
0.2
3.093e+38
0.9
32
Au
339
339
350
339
33
Ag
360
360
360
360
2.985e+38
0.9
3.113e+38
0.9
6.098e+38
1.8
34
Au
368
369
368
371
35
Au
374
376
375
384
36
Au
384
386
386
386
37
Ag
386
387
386
388
7.522e+38
2.2
2.609e+38
0.8
1.013e+39
3.0
38
Au
389
393
393
393
39
Ag
393
399
403
403
7.260e+38
2.1
7.147e+37
0.2
7.975e+38
2.3
40
Ag
403
403
406
405
7.061e+38
2.1
5.043e+37
0.1
7.565e+38
2.2
41
Au
406
408
419
418
42
Ag
447
447
447
447
2.140e+38
0.6
1.748e+38
0.5
3.888e+38
1.1
43
Au
452
453
453
452
44
Au
458
460
458
459
45
Ag
468
468
468
468
5.734e+38
1.7
1.007e+38
0.3
6.741e+38
2.0
46
Ag
470
470
470
470
7.296e+39
21.3
1.170e+38
0.3
7.413e+39
21.6
47
Ag
500
500
500
500
3.426e+40
99.8
6.411e+37
0.2
3.432e+40
100.0
48
Au
531
532
546
531
49
Ag
565
565
565
565
1.263e+39
3.7
1.066e+37
0.0
1.273e+39
3.7
50
Au
568
585
569
581
51
Au
591
596
594
602
52
Ag
631
631
631
631
2.981e+38
0.9
1.074e+38
0.3
4.054e+38
1.2
53
Au
632
633
633
633
54
Ag
633
652
634
637
5.096e+38
1.5
5.631e+37
0.2
5.659e+38
1.6
55
Au
729
729
729
730
56
Au
733
733
733
734
57
Ag
736
736
736
736
2.574e+39
7.5
2.449e+38
0.7
2.819e+39
8.2
58
Ag
751
751
751
751
7.000e+38
2.0
7.173e+38
2.1
1.417e+39
4.1
59
Au
753
753
759
755
60
Au
780
785
780
780
61
Ag
785
789
785
785
1.348e+39
3.9
1.998e+38
0.6
1.548e+39
4.5
62
Ag
797
797
797
797
1.163e+39
3.4
4.189e+38
1.2
1.582e+39
4.6
63
Au
925
925
928
928
64
Ag
928
928
937
931
7.988e+38
2.3
1.003e+39
2.9
1.801e+39
5.2
65
Ag
937
937
938
937
3.532e+38
1.0
4.514e+38
1.3
8.046e+38
2.3
66
Au
942
949
971
971
67
Ag
971
971
982
982
2.556e+38
0.7
1.712e+38
0.5
4.268e+38
1.2
68
Au
983
986
986
986
69
Ag
986
997
998
990
2.651e+38
0.8
2.695e+38
0.8
5.346e+38
1.6
70
Au
998
1010
1013
1021
71
Ag
1026
1026
1026
1026
1.630e+38
0.5
1.803e+38
0.5
3.433e+38
1.0
72
Au
1048
1048
1048
1048
73
Ag
1055
1055
1055
1055
74
Au
1055
1065
1059
1063
3.433e+38
1.0
2.544e+38
0.7
5.978e+38
1.7
75
Ag
1065
1077
1065
1065
2.302e+38
0.7
1.796e+38
0.5
4.098e+38
1.2
76
Au
1079
1081
1081
1081
77
Ag
1081
1090
1095
1081
3.893e+38
1.1
4.085e+38
1.2
7.978e+38
2.3
78
Au
1095
1148
1128
1142
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.