- WOLLASTONITE - CaSiO₃

Theoretical atomic positions and lattice parameters at experimental volum from 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:	2		P-1
Lattice parameters (Å):	4.1942	3.8737		3.7388
Angles (°):	90.1	95.2		103.4

Symmetry (theoretical):

Space group:	2		P-1
Lattice parameters (Å):	7.9223	7.3056		7.0841
Angles (°):	90.1	95.5		103.4

Cell contents:

Number of atoms:	30
Number of atom types:	3
Chemical composition:	0

Atomic positions (theoretical):

Ca:	0.2001	0.4234	0.7627
Ca:	0.2062	0.9305	0.7661
Ca:	0.5058	0.7508	0.5295
Si:	0.1864	0.3870	0.2686
Si:	0.1873	0.9555	0.2687
Si:	0.3977	0.7228	0.0584
O:	0.3026	0.4624	0.4635
O:	0.3016	0.9380	0.4643
O:	0.5721	0.7673	0.1998
O:	0.9842	0.3706	0.2609
O:	0.9838	0.8703	0.2583
O:	0.4010	0.7249	0.8334
O:	0.2251	0.1805	0.2286
O:	0.2746	0.8716	0.0965
O:	0.2744	0.5131	0.0953
Ca:	0.7999	0.5766	0.2373
Ca:	0.7938	0.0695	0.2339
Ca:	0.4942	0.2492	0.4705
Si:	0.8136	0.6130	0.7314
Si:	0.8127	0.0445	0.7313
Si:	0.6023	0.2772	0.9416
O:	0.6974	0.5376	0.5365
O:	0.6984	0.0620	0.5357
O:	0.4279	0.2327	0.8002
O:	0.0158	0.6294	0.7391
O:	0.0162	0.1297	0.7417
O:	0.5990	0.2751	0.1666
O:	0.7749	0.8195	0.7714
O:	0.7254	0.1284	0.9035
O:	0.7256	0.4869	0.9047

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:

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	83	83	83	83	1.187e+38 0.3	1.540e+38 0.3	2.728e+38 0.6
5	Au	107	107	107	107	5.976e+38 1.3	6.228e+37 0.1	6.599e+38 1.5
6	Au	110	110	110	110	2.423e+38 0.5	1.621e+38 0.4	4.044e+38 0.9
7	Ag	112	112	112	112
8	Ag	117	117	117	117	8.787e+38 2.0	5.840e+38 1.3	1.463e+39 3.2
9	Ag	147	147	147	148
10	Au	148	149	150	151
11	Ag	151	151	151	154	7.292e+38 1.6	2.501e+38 0.6	9.793e+38 2.2
12	Ag	155	155	155	158
13	Ag	166	166	166	166	3.091e+38 0.7	2.307e+38 0.5	5.399e+38 1.2
14	Ag	168	168	168	168	1.425e+39 3.2	9.260e+37 0.2	1.518e+39 3.4
15	Au	168	168	168	169
16	Ag	174	174	174	174	2.741e+38 0.6	4.278e+38 1.0	7.019e+38 1.6
17	Au	185	185	185	185	2.184e+38 0.5	1.462e+38 0.3	3.646e+38 0.8
18	Ag	191	194	191	191
19	Au	201	201	201	201	1.857e+38 0.4	1.007e+38 0.2	2.865e+38 0.6
20	Ag	203	203	203	203	5.601e+38 1.2	2.430e+38 0.5	8.031e+38 1.8
21	Au	216	216	216	217
22	Au	218	218	219	221
23	Ag	236	236	236	236	9.964e+38 2.2	3.590e+38 0.8	1.355e+39 3.0
24	Ag	239	240	243	239
25	Au	246	246	246	246	9.616e+38 2.1	3.174e+38 0.7	1.279e+39 2.8
26	Au	252	258	255	252
27	Ag	258	262	258	258	1.599e+38 0.4	7.724e+37 0.2	2.371e+38 0.5
28	Au	266	268	266	266
29	Ag	268	270	268	268	3.922e+38 0.9	1.593e+38 0.4	5.516e+38 1.2
30	Ag	274	277	275	275
31	Au	278	278	278	278	8.862e+37 0.2	1.213e+38 0.3	2.099e+38 0.5
32	Au	282	289	282	287
33	Ag	293	293	293	293	1.607e+38 0.4	9.074e+37 0.2	2.514e+38 0.6
34	Ag	295	298	296	298
35	Ag	299	299	299	299	4.920e+38 1.1	3.362e+38 0.7	8.282e+38 1.8
36	Au	305	307	310	309
37	Au	317	317	317	318
38	Ag	318	318	318	318	1.113e+39 2.5	6.313e+38 1.4	1.744e+39 3.9
39	Au	319	328	319	330
40	Ag	330	330	330	336	3.608e+39 8.0	2.285e+38 0.5	3.836e+39 8.5
41	Au	336	338	337	340
42	Ag	340	340	340	340	1.362e+39 3.0	1.489e+39 3.3	2.851e+39 6.3
43	Ag	340	342	342	348
44	Au	348	348	348	360	1.731e+39 3.8	1.790e+39 4.0	3.521e+39 7.8
45	Ag	361	362	362	364
46	Au	365	365	365	365	1.038e+39 2.3	1.138e+39 2.5	2.176e+39 4.8
47	Ag	388	389	388	388
48	Au	389	390	389	389	9.361e+38 2.1	1.021e+38 0.2	1.038e+39 2.3
49	Ag	403	406	403	404
50	Au	409	409	409	409	3.197e+39 7.1	3.119e+39 6.9	6.316e+39 14.0
51	Ag	414	414	414	414
52	Au	414	414	415	414	2.691e+39 6.0	1.566e+39 3.5	4.257e+39 9.5
53	Ag	443	443	447	443
54	Au	448	448	448	448	5.793e+38 1.3	1.831e+38 0.4	7.624e+38 1.7
55	Au	448	453	450	451
56	Ag	455	465	466	466
57	Au	467	467	467	467	7.677e+38 1.7	1.006e+39 2.2	1.773e+39 3.9
58	Ag	470	470	470	470	4.273e+38 0.9	4.755e+38 1.1	9.028e+38 2.0
59	Au	473	481	481	476
60	Ag	481	494	494	481	3.808e+38 0.8	2.730e+38 0.6	6.539e+38 1.5
61	Au	494	495	497	494	1.817e+38 0.4	1.247e+38 0.3	3.064e+38 0.7
62	Ag	501	501	502	503
63	Au	503	503	503	503	4.427e+38 1.0	5.335e+38 1.2	9.762e+38 2.2
64	Ag	504	505	550	504
65	Au	551	564	562	552
66	Ag	570	570	570	570	1.119e+39 2.5	1.918e+38 0.4	1.311e+39 2.9
67	Ag	618	618	618	618	2.513e+40 55.8	1.661e+38 0.4	2.529e+40 56.2
68	Au	624	624	624	634
69	Au	670	670	672	670
70	Au	673	673	673	673	1.398e+39 3.1	4.853e+38 1.1	1.883e+39 4.2
71	Ag	674	675	677	675
72	Ag	695	695	695	695	3.286e+38 0.7	4.289e+38 1.0	7.575e+38 1.7
73	Au	872	872	872	872	1.938e+39 4.3	1.475e+38 0.3	2.086e+39 4.6
74	Ag	875	886	875	886
75	Au	886	888	893	887
76	Ag	894	894	894	894	7.511e+37 0.2	1.119e+38 0.2	1.870e+38 0.4
77	Au	914	915	915	915
78	Ag	915	917	937	915	1.913e+38 0.4	2.470e+38 0.5	4.383e+38 1.0
79	Ag	937	945	952	952
80	Au	952	952	978	964	4.417e+40 98.1	8.465e+38 1.9	4.501e+40 100.0
81	Ag	980	980	980	980	2.283e+39 5.1	2.385e+39 5.3	4.668e+39 10.4
82	Au	992	992	992	996
83	Au	996	1003	999	1003
84	Ag	1003	1004	1003	1009	5.686e+38 1.3	4.064e+38 0.9	9.750e+38 2.2
85	Ag	1009	1012	1012	1012
86	Au	1012	1024	1014	1032	1.244e+39 2.8	1.118e+39 2.5	2.362e+39 5.2
87	Au	1032	1032	1032	1041	9.108e+39 20.2	2.525e+39 5.6	1.163e+40 25.8
88	Ag	1042	1042	1044	1044
89	Au	1044	1044	1054	1053	6.912e+38 1.5	4.195e+38 0.9	1.111e+39 2.5
90	Ag	1056	1117	1069	1064

No.

Char.

ω TO

ω LOx

ω LOy

ω LOz

I ∥

I ⊥