-    ENSTATITE     -    MgSiO3

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:  61  Pbca 
Lattice parameters (Å):  18.2330  8.8191  5.1802 
Angles (°):  90  90  90 

Symmetry (theoretical): 

Space group:  61  Pbca 
Lattice parameters (Å):  17.9591  8.6470  5.0949 
Angles (°):  90  90  90 

Cell contents: 

Number of atoms:  80 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Mg:  0.3761  0.6560  0.8590 
Mg:  0.3772  0.4859  0.3514 
Si:  0.2714  0.3429  0.0451 
Si:  0.4729  0.3378  0.8030 
O:  0.1827  0.3405  0.0266 
O:  0.3111  0.5050  0.0355 
O:  0.3036  0.2195  0.8302 
O:  0.5622  0.3393  0.8059 
O:  0.4324  0.4833  0.6849 
O:  0.4464  0.1907  0.6125 
Mg:  0.1239  0.3440  0.3590 
Mg:  0.1228  0.5141  0.8514 
Si:  0.2286  0.6571  0.5451 
Si:  0.0271  0.6622  0.3030 
O:  0.3173  0.6595  0.5266 
O:  0.1889  0.4950  0.5355 
O:  0.1964  0.7805  0.3302 
O:  0.9378  0.6607  0.3059 
O:  0.0676  0.5167  0.1849 
O:  0.0536  0.8093  0.1125 
Mg:  0.6239  0.1560  0.6410 
Mg:  0.6228  0.9859  0.1486 
Si:  0.7286  0.8429  0.4549 
Si:  0.5271  0.8378  0.6970 
O:  0.8173  0.8405  0.4734 
O:  0.6889  0.0050  0.4645 
O:  0.6964  0.7195  0.6698 
O:  0.4378  0.8393  0.6941 
O:  0.5676  0.9833  0.8151 
O:  0.5536  0.6907  0.8875 
Mg:  0.8761  0.8440  0.1410 
Mg:  0.8772  0.0141  0.6486 
Si:  0.7714  0.1571  0.9549 
Si:  0.9729  0.1622  0.1970 
O:  0.6827  0.1595  0.9734 
O:  0.8111  0.9950  0.9645 
O:  0.8036  0.2805  0.1698 
O:  0.0622  0.1607  0.1941 
O:  0.9324  0.0167  0.3151 
O:  0.9464  0.3093  0.3875 
Mg:  0.6239  0.3440  0.1410 
Mg:  0.6228  0.5141  0.6486 
Si:  0.7286  0.6571  0.9549 
Si:  0.5271  0.6622  0.1970 
O:  0.8173  0.6595  0.9734 
O:  0.6889  0.4950  0.9645 
O:  0.6964  0.7805  0.1698 
O:  0.4378  0.6607  0.1941 
O:  0.5676  0.5167  0.3151 
O:  0.5536  0.8093  0.3875 
Mg:  0.8761  0.6560  0.6410 
Mg:  0.8772  0.4859  0.1486 
Si:  0.7714  0.3429  0.4549 
Si:  0.9729  0.3378  0.6970 
O:  0.6827  0.3405  0.4734 
O:  0.8111  0.5050  0.4645 
O:  0.8036  0.2195  0.6698 
O:  0.0622  0.3393  0.6941 
O:  0.9324  0.4833  0.8151 
O:  0.9464  0.1907  0.8875 
Mg:  0.3761  0.8440  0.3590 
Mg:  0.3772  0.0141  0.8514 
Si:  0.2714  0.1571  0.5451 
Si:  0.4729  0.1622  0.3030 
O:  0.1827  0.1595  0.5266 
O:  0.3111  0.9950  0.5355 
O:  0.3036  0.2805  0.3302 
O:  0.5622  0.1607  0.3059 
O:  0.4324  0.0167  0.1849 
O:  0.4464  0.3093  0.1125 
Mg:  0.1239  0.1560  0.8590 
Mg:  0.1228  0.9859  0.3514 
Si:  0.2286  0.8429  0.0451 
Si:  0.0271  0.8378  0.8030 
O:  0.3173  0.8405  0.0266 
O:  0.1889  0.0050  0.0355 
O:  0.1964  0.7195  0.8302 
O:  0.9378  0.8393  0.8059 
O:  0.0676  0.9833  0.6849 
O:  0.0536  0.6907  0.6125 
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
B3g
86
86
86
86
5
Ag
87
87
87
87
1.735e+39
6.7
3.571e+37
0.1
1.771e+39
6.9
6
Ag
87
87
87
87
3.510e+38
1.4
7.223e+36
0.0
3.582e+38
1.4
7
B3u
88
88
88
88
8
B2u
120
120
120
120
9
B2g
125
125
125
125
7.761e+37
0.3
1.067e+38
0.4
1.843e+38
0.7
10
B1u
140
140
140
141
11
A1g
143
143
143
143
1.241e+39
4.8
2.256e+38
0.9
1.466e+39
5.7
12
B2g
146
146
146
146
13
B3u
147
148
147
147
14
B1u
149
149
149
150
15
B1g
153
153
153
153
8.503e+36
0.0
1.169e+37
0.0
2.019e+37
0.1
16
A1g
155
155
155
155
3.292e+38
1.3
1.932e+38
0.8
5.224e+38
2.0
17
B2g
160
160
160
160
3.511e+37
0.1
4.828e+37
0.2
8.339e+37
0.3
18
Au
161
161
161
161
19
B1g
162
162
162
162
20
B3g
163
163
163
163
3.974e+37
0.2
5.464e+37
0.2
9.438e+37
0.4
21
B2g
168
168
168
168
1.990e+37
0.1
2.736e+37
0.1
4.726e+37
0.2
22
B2g
168
168
168
168
1.997e+36
0.0
2.746e+36
0.0
4.743e+36
0.0
23
B3g
169
169
169
169
3.587e+38
1.4
4.932e+38
1.9
8.518e+38
3.3
24
B1u
186
186
186
186
25
B1g
188
188
188
188
2.027e+38
0.8
2.787e+38
1.1
4.815e+38
1.9
26
A1g
198
198
198
198
3.470e+38
1.3
1.484e+38
0.6
4.954e+38
1.9
27
B2g
198
198
198
198
1.338e+37
0.1
1.840e+37
0.1
3.178e+37
0.1
28
B1u
199
199
199
200
29
B3u
200
201
200
200
30
A1g
201
201
201
201
2.362e+38
0.9
1.047e+38
0.4
3.410e+38
1.3
31
B2u
205
205
205
205
32
B1g
205
205
205
205
5.040e+38
2.0
6.930e+38
2.7
1.197e+39
4.7
33
B3u
206
209
206
206
34
A1g
212
212
212
212
3.339e+38
1.3
2.504e+38
1.0
5.843e+38
2.3
35
Au
216
216
216
216
36
B3g
220
220
220
220
1.068e+37
0.0
1.468e+37
0.1
2.536e+37
0.1
37
B2u
222
222
222
222
38
B2u
226
226
228
226
39
B2g
228
228
230
228
1.931e+37
0.1
2.655e+37
0.1
4.585e+37
0.2
40
B1u
230
230
233
230
41
B1g
233
233
234
233
2.566e+37
0.1
3.529e+37
0.1
6.095e+37
0.2
42
Au
234
234
234
234
43
B2g
237
237
237
237
44
B3g
238
238
238
238
8.472e+38
3.3
1.165e+39
4.5
2.012e+39
7.8
45
B3u
240
240
240
240
46
B1u
241
241
241
242
47
B2u
242
242
244
243
48
A1g
244
244
246
244
1.446e+39
5.6
9.038e+36
0.0
1.455e+39
5.7
49
B1g
246
246
248
246
3.256e+37
0.1
4.477e+37
0.2
7.733e+37
0.3
50
B3g
253
253
253
253
3.048e+38
1.2
4.191e+38
1.6
7.238e+38
2.8
51
Au
263
263
263
263
52
B2g
265
265
265
265
1.948e+37
0.1
2.679e+37
0.1
4.627e+37
0.2
53
B3u
266
266
266
266
54
A1g
269
269
269
269
3.372e+38
1.3
3.995e+37
0.2
3.772e+38
1.5
55
B2u
278
278
281
278
56
Au
281
281
283
281
57
A1g
283
283
287
283
4.266e+38
1.7
2.006e+38
0.8
6.272e+38
2.4
58
B3u
287
287
288
287
59
B1g
288
288
288
288
9.168e+37
0.4
1.261e+38
0.5
2.178e+38
0.8
60
B1u
289
289
289
290
61
Au
294
294
294
294
62
B2g
294
294
294
294
8.217e+37
0.3
1.130e+38
0.4
1.952e+38
0.8
63
B3g
295
295
295
295
64
B3u
296
296
296
296
65
B2u
296
296
301
296
66
B1u
302
302
302
302
67
B1g
302
302
302
302
5.304e+37
0.2
7.293e+37
0.3
1.260e+38
0.5
68
B3u
306
307
306
306
69
B2g
307
307
307
307
1.639e+38
0.6
2.254e+38
0.9
3.894e+38
1.5
70
B1g
307
307
307
307
6.898e+37
0.3
2.062e+37
0.1
8.960e+37
0.3
71
B1g
307
309
307
307
7.979e+38
3.1
5.578e+37
0.2
8.537e+38
3.3
72
B1u
313
313
313
313
73
B1g
313
313
313
313
6.646e+37
0.3
9.139e+37
0.4
1.578e+38
0.6
74
B3g
314
314
314
314
3.336e+37
0.1
4.587e+37
0.2
7.924e+37
0.3
75
B3u
320
323
320
320
76
B2g
323
327
323
323
1.553e+38
0.6
2.135e+38
0.8
3.688e+38
1.4
77
B3u
328
329
328
328
78
A1g
329
330
329
329
4.441e+38
1.7
3.271e+38
1.3
7.712e+38
3.0
79
Au
330
332
330
330
80
B1u
332
336
332
332
81
Au
336
338
336
336
82
A1g
338
339
338
338
1.249e+39
4.9
2.612e+38
1.0
1.510e+39
5.9
83
B2u
339
346
339
339
84
B3g
346
347
346
346
1.550e+38
0.6
2.131e+38
0.8
3.681e+38
1.4
85
B2g
347
351
347
347
86
B1g
351
352
351
351
1.923e+37
0.1
2.644e+37
0.1
4.566e+37
0.2
87
B2u
352
352
352
352
88
B1u
353
353
353
354
89
Au
360
360
360
360
90
Ag
360
360
360
360
2.633e+37
0.1
4.776e+35
0.0
2.680e+37
0.1
91
Ag
360
360
360
360
1.924e+40
74.7
3.489e+38
1.4
1.959e+40
76.1
92
B3u
361
361
361
361
93
B1g
361
362
361
361
1.310e+38
0.5
1.801e+38
0.7
3.111e+38
1.2
94
B2u
362
364
364
362
95
B2g
364
368
368
364
2.350e+36
0.0
3.231e+36
0.0
5.581e+36
0.0
96
B3g
368
372
375
368
2.863e+38
1.1
3.937e+38
1.5
6.800e+38
2.6
97
B3u
375
375
375
375
98
B1g
375
377
376
375
1.702e+37
0.1
2.340e+37
0.1
4.041e+37
0.2
99
Au
377
380
377
377
100
B2u
380
386
380
380
101
B2g
386
386
386
386
2.276e+38
0.9
2.857e+38
1.1
5.133e+38
2.0
102
B3g
386
389
386
386
1.304e+38
0.5
2.065e+38
0.8
3.369e+38
1.3
103
B1g
389
390
389
389
6.117e+37
0.2
8.411e+37
0.3
1.453e+38
0.6
104
Au
390
392
390
390
105
Ag
393
393
393
393
1.855e+36
0.0
1.141e+36
0.0
2.996e+36
0.0
106
Ag
393
393
393
393
4.567e+38
1.8
2.809e+38
1.1
7.376e+38
2.9
107
B3g
397
397
397
397
3.338e+37
0.1
4.589e+37
0.2
7.927e+37
0.3
108
B2u
401
401
401
401
109
B1u
406
406
406
407
110
B1g
407
407
407
408
2.635e+37
0.1
3.624e+37
0.1
6.259e+37
0.2
111
B3u
408
409
408
409
112
B2u
409
410
410
410
113
B2g
410
410
410
411
114
B1g
411
411
411
411
1.042e+39
4.0
2.522e+38
1.0
1.295e+39
5.0
115
B1g
411
411
411
411
2.276e+39
8.8
3.468e+38
1.3
2.623e+39
10.2
116
Au
411
411
411
415
117
B3g
419
419
419
419
1.591e+37
0.1
2.188e+37
0.1
3.779e+37
0.1
118
B1g
421
421
421
421
1.612e+38
0.6
2.217e+38
0.9
3.829e+38
1.5
119
B3u
422
425
422
422
120
A1g
425
430
425
425
2.819e+39
11.0
2.463e+38
1.0
3.065e+39
11.9
121
Au
430
430
430
430
122
B2u
432
432
432
432
123
B1u
433
433
433
433
124
B2g
434
434
434
434
8.202e+36
0.0
1.128e+37
0.0
1.948e+37
0.1
125
B3u
437
445
437
437
126
B2g
446
446
446
446
8.489e+35
0.0
1.167e+36
0.0
2.016e+36
0.0
127
Ag
446
446
446
446
3.609e+36
0.0
1.203e+36
0.0
4.812e+36
0.0
128
Ag
447
447
447
447
8.654e+38
3.4
3.131e+38
1.2
1.178e+39
4.6
129
B1g
450
450
450
450
7.559e+37
0.3
1.039e+38
0.4
1.795e+38
0.7
130
B3g
450
450
450
450
6.821e+37
0.3
9.379e+37
0.4
1.620e+38
0.6
131
B1u
454
454
454
454
132
B3u
454
462
454
458
133
B1g
462
463
462
462
1.778e+38
0.7
2.445e+38
1.0
4.224e+38
1.6
134
B1u
463
464
463
464
135
A1g
464
465
464
465
9.555e+37
0.4
6.532e+37
0.3
1.609e+38
0.6
136
B2u
465
471
468
468
137
B2g
471
471
471
471
3.908e+37
0.2
5.374e+37
0.2
9.282e+37
0.4
138
Au
472
472
472
472
139
B2u
472
472
473
472
140
B3g
473
473
474
473
1.173e+38
0.5
1.613e+38
0.6
2.787e+38
1.1
141
A1g
474
474
475
474
3.850e+37
0.1
2.128e+37
0.1
5.978e+37
0.2
142
B3g
475
475
479
475
1.218e+38
0.5
1.674e+38
0.7
2.892e+38
1.1
143
B1u
479
479
480
480
144
B2u
480
480
483
481
145
B2u
483
483
491
483
146
B3g
491
491
493
491
1.608e+37
0.1
2.211e+37
0.1
3.818e+37
0.1
147
B1g
493
493
494
493
5.429e+37
0.2
7.465e+37
0.3
1.289e+38
0.5
148
Au
494
494
499
494
149
Au
499
499
503
499
150
B3u
503
503
503
503
151
B1u
503
503
509
509
152
B2g
509
509
509
509
2.572e+36
0.0
3.536e+36
0.0
6.108e+36
0.0
153
B2g
509
509
519
519
4.344e+35
0.0
5.972e+35
0.0
1.032e+36
0.0
154
B1g
519
519
520
520
8.523e+37
0.3
1.172e+38
0.5
2.024e+38
0.8
155
B3u
520
524
524
524
156
B3g
524
524
525
525
3.252e+38
1.3
4.471e+38
1.7
7.723e+38
3.0
157
A1g
525
525
529
528
1.001e+39
3.9
8.263e+37
0.3
1.083e+39
4.2
158
B2g
529
529
531
529
1.936e+37
0.1
2.662e+37
0.1
4.599e+37
0.2
159
Au
531
531
532
531
160
B1g
532
532
534
532
7.972e+37
0.3
1.096e+38
0.4
1.893e+38
0.7
161
B1u
534
534
537
537
162
A1g
537
537
541
541
1.021e+39
4.0
3.567e+37
0.1
1.057e+39
4.1
163
B2g
541
541
541
543
2.750e+36
0.0
3.781e+36
0.0
6.531e+36
0.0
164
B3u
543
544
543
548
165
B2u
548
548
549
549
166
B3g
549
549
551
551
1.490e+38
0.6
2.049e+38
0.8
3.540e+38
1.4
167
A1g
551
551
553
553
2.491e+38
1.0
1.492e+37
0.1
2.640e+38
1.0
168
B3u
553
556
556
556
169
B2g
556
562
557
562
4.816e+36
0.0
6.622e+36
0.0
1.144e+37
0.0
170
B2u
562
563
563
563
171
Au
563
567
567
565
172
B1u
567
571
575
575
173
B1g
575
575
576
576
5.066e+38
2.0
6.966e+38
2.7
1.203e+39
4.7
174
Au
576
576
576
589
175
B3g
589
589
589
590
5.090e+37
0.2
6.999e+37
0.3
1.209e+38
0.5
176
B1g
590
590
590
614
9.249e+37
0.4
1.272e+38
0.5
2.197e+38
0.9
177
B3u
639
649
639
639
178
B1u
649
649
649
651
179
B2g
651
651
651
654
7.842e+37
0.3
1.078e+38
0.4
1.862e+38
0.7
180
A1g
658
658
658
658
1.763e+40
68.5
5.675e+37
0.2
1.769e+40
68.7
181
B3u
673
674
673
673
182
B2g
677
677
677
677
1.367e+37
0.1
1.880e+37
0.1
3.247e+37
0.1
183
A1g
680
680
680
680
1.953e+40
75.9
2.931e+38
1.1
1.982e+40
77.0
184
B1u
686
686
686
695
185
Au
715
715
715
715
186
B2u
718
718
721
718
187
B1g
721
721
724
721
2.503e+36
0.0
3.442e+36
0.0
5.945e+36
0.0
188
B3g
730
730
730
730
5.907e+37
0.2
8.122e+37
0.3
1.403e+38
0.5
189
Au
731
731
731
731
190
B2u
738
738
741
738
191
B1g
746
746
746
746
3.155e+36
0.0
4.339e+36
0.0
7.494e+36
0.0
192
B3g
747
747
747
747
5.096e+38
2.0
7.006e+38
2.7
1.210e+39
4.7
193
B1u
834
834
834
834
194
B3u
834
834
834
835
195
Ag
835
835
835
835
2.979e+38
1.2
4.097e+38
1.6
7.076e+38
2.7
196
B2g
835
835
835
867
5.998e+38
2.3
4.456e+38
1.7
1.045e+39
4.1
197
B2u
878
878
878
878
198
Au
878
878
885
878
199
B1g
887
887
887
887
3.370e+37
0.1
4.633e+37
0.2
8.003e+37
0.3
200
B2u
890
890
893
890
201
B3g
893
893
893
893
2.488e+35
0.0
3.421e+35
0.0
5.909e+35
0.0
202
B3g
893
893
903
893
2.791e+37
0.1
3.838e+37
0.1
6.630e+37
0.3
203
B1g
903
903
905
903
6.888e+37
0.3
9.471e+37
0.4
1.636e+38
0.6
204
B3g
905
905
906
905
1.311e+37
0.1
1.803e+37
0.1
3.114e+37
0.1
205
Au
909
909
909
909
206
B3g
910
910
910
910
9.853e+37
0.4
1.355e+38
0.5
2.340e+38
0.9
207
B2u
913
913
917
913
208
A1g
917
917
918
917
1.296e+39
5.0
3.414e+38
1.3
1.638e+39
6.4
209
B1u
918
918
922
922
210
B1g
922
922
922
922
6.131e+37
0.2
7.835e+37
0.3
1.397e+38
0.5
211
B2g
922
922
923
923
1.808e+38
0.7
2.545e+38
1.0
4.353e+38
1.7
212
B3u
923
923
923
928
213
A1g
928
928
928
930
2.560e+39
9.9
1.341e+38
0.5
2.694e+39
10.5
214
B3u
930
952
930
952
215
B2g
952
969
952
965
2.360e+36
0.0
3.245e+36
0.0
5.606e+36
0.0
216
B1u
969
984
969
992
217
B1u
997
997
997
1002
218
B2u
1002
1002
1003
1003
219
B3g
1003
1003
1003
1003
2.438e+38
0.9
3.352e+38
1.3
5.790e+38
2.2
220
B3u
1003
1007
1007
1007
221
A1g
1007
1013
1014
1014
2.352e+40
91.4
2.221e+39
8.6
2.574e+40
100.0
222
B2g
1014
1014
1015
1017
8.216e+37
0.3
1.130e+38
0.4
1.951e+38
0.8
223
Au
1017
1017
1017
1018
224
B1g
1018
1018
1018
1019
7.422e+37
0.3
1.021e+38
0.4
1.763e+38
0.7
225
B2u
1019
1019
1021
1020
226
B3g
1030
1030
1030
1030
3.757e+38
1.5
5.165e+38
2.0
8.922e+38
3.5
227
A1g
1031
1031
1031
1031
1.717e+40
66.7
6.527e+38
2.5
1.782e+40
69.2
228
B2g
1032
1032
1032
1032
6.798e+37
0.3
9.348e+37
0.4
1.615e+38
0.6
229
Au
1038
1038
1038
1038
230
B1u
1041
1041
1041
1042
231
A1g
1042
1042
1042
1047
3.983e+39
15.5
2.946e+38
1.1
4.278e+39
16.6
232
B1g
1047
1047
1047
1048
2.490e+38
1.0
3.423e+38
1.3
5.913e+38
2.3
233
B3u
1051
1058
1051
1051
234
B1g
1058
1062
1058
1058
3.630e+37
0.1
4.992e+37
0.2
8.622e+37
0.3
235
B3g
1062
1066
1062
1062
1.040e+38
0.4
1.430e+38
0.6
2.470e+38
1.0
236
Au
1066
1069
1066
1066
237
B2u
1069
1118
1126
1069
238
B1u
1126
1126
1139
1134
239
B2g
1144
1144
1144
1144
5.892e+36
0.0
8.101e+36
0.0
1.399e+37
0.1
240
B3u
1147
1149
1147
1147
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.