- AMEGHINITE - NaB₃O₂(OH)₄

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:	15		C2/c
Lattice parameters (Å):	9.7517	5.2293		3.3476
Angles (°):	18.428	9.882		6.326

Symmetry (theoretical):

Space group:	15		C2/c
Lattice parameters (Å):	10.1511	10.1511		6.0402
Angles (°):	77.71	102.28		123.46

Cell contents:

Number of atoms:	60
Number of atom types:	4
Chemical composition:	0

Atomic positions (theoretical):

Na:	0.4104	0.0648	0.0979
B:	0.5081	0.8298	0.4434
B:	0.8044	0.9981	0.4951
B:	0.6743	0.7151	0.4815
O:	0.7028	0.5992	0.4920
O:	0.4551	0.8575	0.2097
O:	0.4023	0.7987	0.6006
O:	0.9407	0.1403	0.5174
O:	0.8101	0.8673	0.4788
O:	0.6628	0.9778	0.5004
O:	0.5318	0.6942	0.4849
H:	0.6101	0.4846	0.5009
H:	0.3573	0.7540	0.1615
H:	0.3652	0.8747	0.5547
H:	0.0373	0.1340	0.5246
Na:	0.0648	0.4104	0.4021
B:	0.8298	0.5081	0.0566
B:	0.9981	0.8044	0.0049
B:	0.7151	0.6743	0.0185
O:	0.5992	0.7028	0.0080
O:	0.8575	0.4551	0.2903
O:	0.7987	0.4023	0.8994
O:	0.1403	0.9407	0.9826
O:	0.8673	0.8101	0.0212
O:	0.9778	0.6628	0.9996
O:	0.6942	0.5318	0.0151
H:	0.4846	0.6101	0.9991
H:	0.7540	0.3573	0.3385
H:	0.8747	0.3652	0.9453
H:	0.1340	0.0373	0.9754
Na:	0.5896	0.9352	0.9021
B:	0.4919	0.1702	0.5566
B:	0.1956	0.0019	0.5049
B:	0.3257	0.2849	0.5185
O:	0.2972	0.4008	0.5080
O:	0.5449	0.1425	0.7903
O:	0.5977	0.2013	0.3994
O:	0.0593	0.8597	0.4826
O:	0.1899	0.1327	0.5212
O:	0.3372	0.0222	0.4996
O:	0.4682	0.3058	0.5151
H:	0.3899	0.5154	0.4991
H:	0.6427	0.2460	0.8385
H:	0.6348	0.1253	0.4453
H:	0.9627	0.8660	0.4754
Na:	0.9352	0.5896	0.5979
B:	0.1702	0.4919	0.9434
B:	0.0019	0.1956	0.9951
B:	0.2849	0.3257	0.9815
O:	0.4008	0.2972	0.9920
O:	0.1425	0.5449	0.7097
O:	0.2013	0.5977	0.1006
O:	0.8597	0.0593	0.0174
O:	0.1327	0.1899	0.9788
O:	0.0222	0.3372	0.0004
O:	0.3058	0.4682	0.9849
H:	0.5154	0.3899	0.0009
H:	0.2460	0.6427	0.6615
H:	0.1253	0.6348	0.0547
H:	0.8660	0.9627	0.0246

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	Bu	75	75	75	76
5	Ag	81	81	81	81	1.289e+39 1.0	1.204e+39 1.0	2.492e+39 2.0
6	Au	82	82	82	82
7	Bg	88	88	88	88	5.270e+38 0.4	8.891e+38 0.7	1.416e+39 1.1
8	Bu	93	94	93	94
9	Au	100	100	100	100
10	Ag	114	114	114	114	9.368e+38 0.7	7.632e+38 0.6	1.700e+39 1.3
11	Bu	118	118	118	124
12	Bu	127	127	127	128
13	Ag	130	130	130	130	1.465e+39 1.2	1.825e+39 1.4	3.289e+39 2.6
14	Bg	134	134	134	134	3.468e+38 0.3	4.769e+38 0.4	8.238e+38 0.7
15	Au	135	135	135	135
16	Bg	140	140	140	140	7.553e+38 0.6	1.175e+39 0.9	1.931e+39 1.5
17	Ag	143	143	143	143	3.350e+39 2.7	3.732e+39 3.0	7.082e+39 5.6
18	Au	144	144	144	144
19	Ag	149	149	149	149	2.315e+38 0.2	1.726e+38 0.1	4.041e+38 0.3
20	Bg	152	152	152	152	7.514e+38 0.6	1.141e+39 0.9	1.892e+39 1.5
21	Bg	159	159	159	159	7.037e+37 0.1	7.678e+37 0.1	1.471e+38 0.1
22	Bu	160	160	160	161
23	Au	163	163	163	163
24	Bg	173	173	173	173	1.064e+39 0.8	1.433e+39 1.1	2.497e+39 2.0
25	Au	177	177	180	177
26	Bu	180	180	180	180
27	Ag	180	181	182	181	3.513e+38 0.3	1.892e+38 0.1	5.405e+38 0.4
28	Au	190	190	194	190
29	Bg	194	194	196	194	1.728e+39 1.4	2.424e+39 1.9	4.152e+39 3.3
30	Bu	196	196	196	196
31	Au	196	197	197	197
32	Ag	197	197	199	197	9.182e+37 0.1	5.469e+37 0.0	1.465e+38 0.1
33	Bg	199	199	200	199	6.446e+38 0.5	7.333e+38 0.6	1.378e+39 1.1
34	Au	212	212	213	212
35	Bg	215	215	215	215	1.509e+38 0.1	1.328e+38 0.1	2.837e+38 0.2
36	Ag	215	215	215	215	2.706e+38 0.2	3.656e+38 0.3	6.362e+38 0.5
37	Ag	225	225	225	225	1.521e+38 0.1	1.168e+38 0.1	2.689e+38 0.2
38	Bg	227	227	227	227	4.631e+38 0.4	6.583e+38 0.5	1.121e+39 0.9
39	Bu	228	232	228	230
40	Au	232	232	232	232
41	Bu	237	237	237	237
42	Ag	237	244	237	244	5.530e+38 0.4	2.854e+38 0.2	8.384e+38 0.7
43	Bg	244	246	244	244	1.428e+38 0.1	2.385e+38 0.2	3.813e+38 0.3
44	Ag	247	247	247	247	5.315e+38 0.4	1.962e+38 0.2	7.276e+38 0.6
45	Bg	255	255	255	255	1.584e+37 0.0	1.700e+37 0.0	3.284e+37 0.0
46	Au	258	258	258	258
47	Bu	272	272	272	272
48	Ag	272	272	272	281	2.360e+38 0.2	1.822e+38 0.1	4.182e+38 0.3
49	Ag	346	346	346	346	2.378e+38 0.2	1.775e+38 0.1	4.153e+38 0.3
50	Bg	353	353	353	353	3.390e+38 0.3	4.661e+38 0.4	8.051e+38 0.6
51	Au	360	360	361	360
52	Ag	364	364	364	364	3.048e+37 0.0	4.303e+36 0.0	3.478e+37 0.0
53	Bu	368	368	368	369
54	Bg	374	374	374	374	7.878e+37 0.1	9.109e+37 0.1	1.699e+38 0.1
55	Ag	382	382	382	382	1.127e+39 0.9	1.137e+38 0.1	1.241e+39 1.0
56	Bg	384	384	384	384	1.536e+39 1.2	1.963e+39 1.6	3.499e+39 2.8
57	Au	400	400	400	400
58	Bu	400	406	400	400
59	Au	416	416	417	416
60	Bg	421	421	421	421	6.917e+38 0.5	7.381e+38 0.6	1.430e+39 1.1
61	Bu	430	430	430	431
62	Ag	434	434	434	434	6.189e+38 0.5	3.769e+38 0.3	9.958e+38 0.8
63	Bu	443	444	443	443
64	Au	463	463	464	463
65	Ag	472	472	472	472	1.831e+39 1.5	1.410e+39 1.1	3.241e+39 2.6
66	Bg	475	475	475	475	3.928e+37 0.0	5.940e+37 0.0	9.868e+37 0.1
67	Au	498	498	499	498
68	Bu	499	503	499	499
69	Bu	507	507	507	507
70	Au	507	512	512	507
71	Ag	512	512	513	512	8.752e+39 6.9	3.371e+38 0.3	9.089e+39 7.2
72	Bg	516	516	516	516	1.380e+39 1.1	2.064e+39 1.6	3.444e+39 2.7
73	Bu	524	525	524	525
74	Ag	532	532	532	532	5.042e+39 4.0	3.821e+38 0.3	5.424e+39 4.3
75	Au	546	546	547	546
76	Bg	547	547	551	547	3.590e+38 0.3	4.639e+38 0.4	8.229e+38 0.7
77	Bg	578	578	578	578	8.795e+37 0.1	1.300e+38 0.1	2.179e+38 0.2
78	Ag	584	584	584	584	4.760e+38 0.4	3.623e+38 0.3	8.383e+38 0.7
79	Bu	600	600	600	601
80	Bg	602	602	602	602	2.486e+38 0.2	4.194e+38 0.3	6.680e+38 0.5
81	Au	615	615	615	615
82	Bu	625	625	625	625
83	Bg	626	626	626	626	5.193e+39 4.1	1.363e+38 0.1	5.329e+39 4.2
84	Ag	626	626	626	626	1.161e+40 9.2	1.415e+38 0.1	1.175e+40 9.3
85	Au	630	630	630	630
86	Bu	630	631	630	630
87	Ag	633	633	633	633	1.639e+40 13.0	5.999e+37 0.0	1.645e+40 13.0
88	Au	642	642	643	642
89	Bu	651	651	651	662
90	Bg	662	662	662	673	5.565e+38 0.4	7.937e+38 0.6	1.350e+39 1.1
91	Ag	680	680	680	680	2.565e+39 2.0	1.585e+39 1.3	4.150e+39 3.3
92	Au	682	682	682	682
93	Bg	752	752	752	752	1.124e+38 0.1	1.444e+38 0.1	2.568e+38 0.2
94	Ag	756	756	756	756	8.845e+39 7.0	2.523e+38 0.2	9.097e+39 7.2
95	Au	769	769	769	769
96	Bu	770	772	770	770
97	Ag	850	850	850	850	8.835e+38 0.7	3.780e+38 0.3	1.261e+39 1.0
98	Bg	854	854	854	854	3.150e+38 0.2	4.188e+38 0.3	7.338e+38 0.6
99	Au	860	860	871	860
100	Bg	871	871	871	871
101	Bu	871	875	872	872	7.842e+38 0.6	9.606e+38 0.8	1.745e+39 1.4
102	Bu	880	882	880	880
103	Au	882	882	884	882
104	Ag	884	884	897	884	7.194e+39 5.7	3.112e+38 0.2	7.506e+39 5.9
105	Bu	897	901	901	899
106	Ag	901	905	903	901	1.769e+38 0.1	2.322e+38 0.2	4.091e+38 0.3
107	Bu	905	907	905	907
108	Bg	907	912	907	913	7.288e+37 0.1	1.127e+38 0.1	1.856e+38 0.1
109	Au	913	913	913	914
110	Ag	915	915	915	915	5.256e+38 0.4	5.118e+37 0.0	5.768e+38 0.5
111	Bu	915	920	915	920
112	Bg	920	924	920	929	3.325e+38 0.3	3.661e+38 0.3	6.986e+38 0.6
113	Ag	929	929	929	931	2.770e+38 0.2	3.581e+38 0.3	6.351e+38 0.5
114	Bg	943	943	943	943	4.939e+38 0.4	8.145e+38 0.6	1.308e+39 1.0
115	Bg	973	973	973	973	2.377e+38 0.2	3.785e+38 0.3	6.162e+38 0.5
116	Au	974	974	976	974
117	Au	985	985	986	985
118	Ag	1001	1001	1001	1001	1.983e+39 1.6	4.153e+38 0.3	2.399e+39 1.9
119	Au	1002	1002	1004	1002
120	Bu	1008	1013	1008	1009
121	Bu	1016	1017	1016	1017
122	Bg	1017	1017	1017	1017	2.524e+38 0.2	3.703e+38 0.3	6.227e+38 0.5
123	Ag	1018	1018	1018	1018	1.428e+38 0.1	2.315e+37 0.0	1.660e+38 0.1
124	Au	1019	1019	1029	1019
125	Bg	1055	1055	1055	1055	1.751e+37 0.0	1.886e+37 0.0	3.637e+37 0.0
126	Au	1056	1056	1056	1056
127	Bu	1056	1057	1057	1067
128	Ag	1067	1067	1067	1084	1.558e+39 1.2	1.208e+39 1.0	2.766e+39 2.2
129	Ag	1084	1084	1084	1092	1.084e+39 0.9	2.484e+38 0.2	1.332e+39 1.1
130	Au	1101	1101	1102	1101
131	Bu	1102	1117	1102	1117
132	Bg	1117	1128	1117	1121	9.166e+37 0.1	1.282e+38 0.1	2.199e+38 0.2
133	Bu	1201	1205	1201	1201
134	Au	1206	1206	1222	1206
135	Bu	1226	1226	1226	1226
136	Au	1226	1235	1232	1229
137	Bg	1235	1238	1235	1235	5.763e+36 0.0	8.459e+36 0.0	1.422e+37 0.0
138	Ag	1248	1248	1248	1248	1.372e+38 0.1	1.011e+38 0.1	2.383e+38 0.2
139	Bu	1264	1270	1264	1274
140	Bg	1274	1274	1274	1281	4.893e+38 0.4	6.345e+38 0.5	1.124e+39 0.9
141	Ag	1281	1281	1281	1285	1.432e+39 1.1	1.667e+38 0.1	1.599e+39 1.3
142	Au	1291	1291	1291	1291
143	Bg	1302	1302	1302	1302	2.665e+38 0.2	4.227e+38 0.3	6.892e+38 0.5
144	Ag	1310	1310	1310	1310	1.351e+39 1.1	1.740e+37 0.0	1.369e+39 1.1
145	Au	1313	1313	1325	1313
146	Bu	1325	1327	1328	1326
147	Bg	1332	1332	1332	1332	2.370e+38 0.2	3.074e+38 0.2	5.444e+38 0.4
148	Ag	1343	1343	1343	1343	1.056e+39 0.8	3.343e+38 0.3	1.390e+39 1.1
149	Bu	1346	1346	1346	1346
150	Bg	1354	1354	1354	1354	3.663e+36 0.0	6.166e+36 0.0	9.830e+36 0.0
151	Ag	1359	1359	1359	1359	1.027e+39 0.8	1.036e+38 0.1	1.131e+39 0.9
152	Au	1360	1360	1387	1360
153	Bu	1387	1391	1391	1387
154	Ag	1391	1391	1391	1391	5.545e+38 0.4	2.342e+38 0.2	7.887e+38 0.6
155	Bg	1391	1405	1397	1391	7.003e+38 0.6	1.958e+38 0.2	8.961e+38 0.7
156	Au	1409	1409	1414	1409
157	Bu	1462	1462	1462	1462
158	Ag	1462	1463	1462	1462	1.330e+39 1.1	7.966e+38 0.6	2.127e+39 1.7
159	Bg	1467	1467	1467	1467	2.370e+38 0.2	3.076e+38 0.2	5.446e+38 0.4
160	Au	1467	1467	1480	1467
161	Au	1488	1488	1506	1488
162	Bg	1506	1506	1532	1506	3.291e+38 0.3	5.355e+38 0.4	8.646e+38 0.7
163	Bu	1533	1540	1533	1533
164	Ag	1540	1598	1540	1540	2.663e+39 2.1	3.520e+38 0.3	3.015e+39 2.4
165	Bg	2800	2800	2800	2800	1.674e+40 13.3	6.698e+39 5.3	2.344e+40 18.6
166	Ag	2801	2801	2801	2801	7.541e+39 6.0	8.453e+39 6.7	1.599e+40 12.7
167	Ag	2805	2805	2805	2805	1.133e+41 89.8	1.292e+40 10.2	1.262e+41 100.0
168	Bu	2807	2809	2807	2819
169	Au	2819	2819	2826	2823
170	Bu	2842	2845	2842	2843
171	Au	2891	2891	2902	2891
172	Bg	2902	2902	2917	2902	1.948e+40 15.4	2.109e+40 16.7	4.057e+40 32.1
173	Bg	2917	2917	2925	2917	5.695e+39 4.5	9.610e+39 7.6	1.530e+40 12.1
174	Ag	2925	2925	2983	2925	3.900e+40 30.9	3.297e+39 2.6	4.230e+40 33.5
175	Au	2984	2984	2990	2984
176	Bu	2990	3049	3037	2990
177	Bg	3087	3087	3087	3087	2.797e+39 2.2	4.100e+39 3.2	6.897e+39 5.5
178	Ag	3092	3092	3092	3092	6.377e+40 50.5	2.123e+40 16.8	8.500e+40 67.3
179	Au	3147	3147	3152	3147
180	Bu	3152	3190	3152	3152

No.

Char.

ω TO

ω LOx

ω LOy

ω LOz

I ∥

I ⊥