- SIBIRSKITE - CaHBO₃

Abinit Trouiller-Martins pseudopotential for Ca. 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:	14		P2_1/a
Lattice parameters (Å):	15.1920	5.6290		3.7067
Angles (°):	90.0	104.5		90.0

Symmetry (theoretical):

Space group:	14		P2_1/a
Lattice parameters (Å):	14.6307	5.5671		3.7272
Angles (°):	90.0	104.1		90.0

Cell contents:

Number of atoms:	24
Number of atom types:	4
Chemical composition:	0

Atomic positions (theoretical):

Ca:	0.1610	0.0115	0.2739
B:	0.1193	0.5066	0.8448
H:	0.0049	0.7045	0.5138
O:	0.2002	0.5156	0.1180
O:	0.0768	0.7205	0.7041
O:	0.0792	0.2942	0.7071
Ca:	0.3390	0.5115	0.7261
B:	0.3807	0.0066	0.1552
H:	0.4951	0.2045	0.4862
O:	0.2998	0.0156	0.8820
O:	0.4232	0.2205	0.2959
O:	0.4208	0.7942	0.2929
Ca:	0.8390	0.9885	0.7261
B:	0.8807	0.4934	0.1552
H:	0.9951	0.2955	0.4862
O:	0.7998	0.4844	0.8820
O:	0.9232	0.2795	0.2959
O:	0.9208	0.7058	0.2929
Ca:	0.6610	0.4885	0.2739
B:	0.6193	0.9934	0.8448
H:	0.5049	0.7955	0.5138
O:	0.7002	0.9844	0.1180
O:	0.5768	0.7795	0.7041
O:	0.5792	0.2058	0.7071

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	38	38	38	38	9.703e+38 1.4	6.844e+38 1.0	1.655e+39 2.4
5	Bg	47	47	47	47	5.186e+36 0.0	7.130e+36 0.0	1.232e+37 0.0
6	Au	102	102	102	102
7	Bu	105	105	105	105
8	Bg	119	119	119	119	4.507e+39 6.5	7.184e+39 10.3	1.169e+40 16.8
9	Ag	129	129	129	129	4.636e+39 6.7	1.322e+39 1.9	5.958e+39 8.6
10	Ag	147	147	147	147	2.569e+37 0.0	2.549e+37 0.0	5.118e+37 0.1
11	Bg	157	157	157	157	1.413e+40 20.3	2.359e+40 33.9	3.771e+40 54.1
12	Bg	166	166	166	166	1.454e+39 2.1	1.806e+39 2.6	3.259e+39 4.7
13	Au	175	175	175	175
14	Ag	178	178	178	178	9.440e+38 1.4	6.177e+38 0.9	1.562e+39 2.2
15	Au	185	185	186	185
16	Ag	187	187	187	187	9.642e+39 13.8	6.481e+39 9.3	1.612e+40 23.1
17	Au	190	190	190	190
18	Bu	191	192	191	192
19	Bu	196	202	196	199
20	Bg	202	210	202	202	8.071e+39 11.6	1.006e+40 14.4	1.813e+40 26.0
21	Au	210	211	210	210
22	Ag	211	217	211	211	2.324e+39 3.3	1.720e+39 2.5	4.044e+39 5.8
23	Bu	229	235	229	230
24	Au	235	243	243	235
25	Bg	243	244	244	243	2.564e+39 3.7	3.012e+39 4.3	5.575e+39 8.0
26	Ag	244	251	251	244	3.163e+40 45.4	8.751e+39 12.6	4.039e+40 58.0
27	Bg	251	251	252	251	2.533e+39 3.6	2.694e+39 3.9	5.227e+39 7.5
28	Bu	252	257	260	259
29	Bu	260	262	262	262
30	Au	262	272	272	272
31	Ag	272	282	282	282	5.038e+39 7.2	1.047e+39 1.5	6.086e+39 8.7
32	Bg	282	316	332	317	8.054e+39 11.6	8.623e+39 12.4	1.668e+40 23.9
33	Ag	333	333	333	333	1.127e+40 16.2	1.668e+39 2.4	1.293e+40 18.6
34	Au	356	356	359	356
35	Bg	359	359	368	359	9.338e+38 1.3	1.089e+39 1.6	2.023e+39 2.9
36	Bu	368	373	369	374
37	Ag	485	485	485	485	1.745e+40 25.0	1.110e+40 15.9	2.854e+40 41.0
38	Bg	492	492	492	492	3.932e+38 0.6	5.979e+38 0.9	9.911e+38 1.4
39	Au	598	598	598	598
40	Bu	601	601	601	601
41	Ag	604	604	604	604	3.177e+39 4.6	1.357e+39 1.9	4.534e+39 6.5
42	Bg	607	607	607	607	7.439e+38 1.1	7.923e+38 1.1	1.536e+39 2.2
43	Bu	658	678	658	675
44	Au	683	683	686	683
45	Bu	694	700	694	700
46	Au	700	700	700	700	4.155e+39 6.0	3.274e+38 0.5	4.482e+39 6.4
47	Ag	700	700	700	700	7.990e+39 11.5	5.496e+38 0.8	8.540e+39 12.3
48	Bg	700	704	701	707
49	Bu	884	887	884	887
50	Ag	887	888	887	888	5.567e+40 79.9	1.399e+40 20.1	6.966e+40 100.0
51	Bg	888	891	888	888	3.794e+38 0.5	5.217e+38 0.7	9.011e+38 1.3
52	Au	891	891	891	891
53	Ag	1042	1042	1042	1042	1.996e+40 28.7	1.813e+40 26.0	3.809e+40 54.7
54	Bg	1043	1043	1043	1043	3.664e+38 0.5	4.130e+38 0.6	7.794e+38 1.1
55	Bu	1204	1218	1204	1218
56	Ag	1218	1218	1218	1218	1.931e+38 0.3	1.421e+38 0.2	3.352e+38 0.5
57	Bg	1218	1243	1218	1246	7.716e+38 1.1	1.077e+39 1.5	1.849e+39 2.7
58	Au	1246	1246	1246	1254
59	Bu	1256	1281	1256	1281
60	Au	1281	1282	1284	1283
61	Bu	1284	1314	1309	1314
62	Ag	1314	1327	1314	1327	9.913e+38 1.4	1.274e+39 1.8	2.265e+39 3.3
63	Au	1327	1338	1337	1345
64	Bg	1348	1348	1348	1348	1.090e+38 0.2	1.547e+38 0.2	2.637e+38 0.4
65	Bu	1443	1445	1443	1445
66	Au	1445	1446	1484	1446
67	Bg	1484	1484	1484	1484	1.383e+39 2.0	2.228e+39 3.2	3.611e+39 5.2
68	Ag	1485	1485	1485	1485	1.260e+40 18.1	4.727e+39 6.8	1.733e+40 24.9
69	Ag	1553	1553	1553	1553	1.995e+40 28.6	2.009e+40 28.8	4.004e+40 57.5
70	Bg	1556	1556	1556	1556	7.301e+38 1.0	1.232e+39 1.8	1.962e+39 2.8
71	Bu	1690	1941	1690	1814
72	Au	2014	2014	2014	2014

No.

Char.

ω TO

ω LOx

ω LOy

ω LOz

I ∥

I ⊥