- KOTTIGITE - Zn₃(AsO₄)₂8H₂O

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:	12		C2/m
Lattice parameters (Å):	12.2960	11.3130		6.1140
Angles (°):	90	105.21		90

Symmetry (theoretical):

Space group:	12		C2/m
Lattice parameters (Å):	0.5292	0.5292		0.5292
Angles (°):	80.83	99.16		74.75

Cell contents:

Number of atoms:	37
Number of atom types:	4
Chemical composition:	0

Atomic positions (theoretical):

Zn:	0.0000	0.0000	0.0000
Zn:	0.3831	0.3831	0.0000
As:	0.3138	0.6862	0.3800
O:	0.1475	0.8525	0.3974
O:	0.4123	0.5877	0.7287
O:	0.4438	0.7725	0.2091
O:	0.2118	0.0167	0.8138
O:	0.6398	0.8143	0.7115
H:	0.8002	0.0405	0.3566
H:	0.6864	0.0624	0.0385
H:	0.4162	0.1846	0.4899
H:	0.2398	0.1921	0.2774
As:	0.6862	0.3138	0.6200
O:	0.8525	0.1475	0.6026
O:	0.5877	0.4123	0.2713
O:	0.7725	0.4438	0.7909
O:	0.0167	0.2118	0.1862
O:	0.8143	0.6398	0.2885
H:	0.0405	0.8002	0.6434
H:	0.0624	0.6864	0.9615
H:	0.1846	0.4162	0.5101
H:	0.1921	0.2398	0.7226
Zn:	0.6169	0.6169	0.0000
O:	0.5562	0.2275	0.7909
O:	0.7882	0.9833	0.1862
O:	0.3602	0.1857	0.2885
H:	0.1998	0.9595	0.6434
H:	0.3136	0.9376	0.9615
H:	0.5838	0.8154	0.5101
H:	0.7602	0.8079	0.7226
O:	0.2275	0.5562	0.2091
O:	0.9833	0.7882	0.8138
O:	0.1857	0.3602	0.7115
H:	0.9595	0.1998	0.3566
H:	0.9376	0.3136	0.0385
H:	0.8154	0.5838	0.4899
H:	0.8079	0.7602	0.2774

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	Bg	67	67	67	67	5.040e+38 0.3	7.902e+38 0.4	1.294e+39 0.7
5	Bg	96	96	96	96	1.647e+38 0.1	1.824e+38 0.1	3.471e+38 0.2
6	Ag	99	99	99	99	7.359e+39 3.8	2.842e+39 1.5	1.020e+40 5.2
7	Au	99	99	100	99
8	Bu	104	104	104	104
9	Bg	108	108	108	108	7.498e+38 0.4	8.197e+38 0.4	1.570e+39 0.8
10	Bu	128	128	128	135
11	Ag	141	141	141	141	6.266e+39 3.2	2.127e+39 1.1	8.392e+39 4.3
12	Au	149	149	151	149
13	Bu	151	152	154	151
14	Au	154	154	156	154
15	Bu	156	158	158	158
16	Bg	158	160	160	160	6.878e+39 3.5	1.130e+40 5.8	1.818e+40 9.3
17	Bg	160	162	164	164	3.187e+39 1.6	3.431e+39 1.8	6.618e+39 3.4
18	Bu	164	164	164	164
19	Ag	164	172	172	169	2.320e+38 0.1	1.486e+38 0.1	3.806e+38 0.2
20	Ag	172	176	172	172	2.626e+39 1.3	2.777e+39 1.4	5.403e+39 2.8
21	Au	182	182	182	182	5.710e+37 0.0	6.074e+37 0.0	1.178e+38 0.1
22	Bg	182	182	183	182	5.785e+39 3.0	6.154e+39 3.2	1.194e+40 6.1
23	Bu	197	201	197	201
24	Ag	201	203	201	203	2.453e+39 1.3	1.733e+39 0.9	4.186e+39 2.1
25	Bg	203	203	203	203	1.244e+39 0.6	1.324e+39 0.7	2.568e+39 1.3
26	Au	203	203	204	204
27	Bu	206	210	206	210
28	Ag	210	217	210	214	5.892e+40 30.2	2.084e+39 1.1	6.101e+40 31.2
29	Au	217	222	221	217
30	Bg	222	222	222	222	1.296e+39 0.7	1.623e+39 0.8	2.918e+39 1.5
31	Au	237	237	237	237
32	Bg	248	248	248	248	8.211e+38 0.4	8.726e+38 0.4	1.694e+39 0.9
33	Ag	255	255	255	255	3.893e+39 2.0	3.612e+39 1.8	7.505e+39 3.8
34	Bu	259	260	259	260
35	Au	265	265	266	265
36	Bu	273	276	273	273
37	Bg	280	280	280	280	2.514e+39 1.3	4.236e+39 2.2	6.750e+39 3.5
38	Ag	284	284	284	284	2.845e+40 14.6	4.889e+39 2.5	3.334e+40 17.1
39	Bu	300	303	300	301
40	Ag	312	312	312	312	5.307e+39 2.7	7.077e+39 3.6	1.238e+40 6.3
41	Bu	322	324	322	324
42	Au	324	329	326	339
43	Ag	339	339	339	341	5.681e+39 2.9	3.973e+39 2.0	9.654e+39 4.9
44	Bg	344	344	344	344	1.957e+39 1.0	2.754e+39 1.4	4.711e+39 2.4
45	Bu	363	364	363	368
46	Au	373	373	374	373
47	Ag	382	382	382	382	1.258e+40 6.4	3.217e+39 1.6	1.580e+40 8.1
48	Bg	383	383	383	383	6.642e+39 3.4	7.399e+39 3.8	1.404e+40 7.2
49	Bu	383	401	383	384
50	Au	402	402	412	402
51	Ag	412	412	416	412	1.991e+40 10.2	7.472e+39 3.8	2.738e+40 14.0
52	Bu	416	420	419	424
53	Bg	424	424	424	438	1.271e+40 6.5	1.975e+40 10.1	3.246e+40 16.6
54	Ag	438	438	438	453	1.645e+40 8.4	2.001e+40 10.2	3.646e+40 18.7
55	Au	453	453	469	459
56	Bu	612	645	612	614
57	Bg	678	678	678	678	4.766e+38 0.2	5.468e+38 0.3	1.023e+39 0.5
58	Ag	699	699	699	699	2.506e+40 12.8	6.194e+39 3.2	3.126e+40 16.0
59	Au	717	717	719	717
60	Bu	719	728	722	720
61	Au	728	731	731	728
62	Bg	731	738	739	731	2.370e+39 1.2	3.808e+39 1.9	6.178e+39 3.2
63	Bu	739	741	741	741
64	Ag	741	747	751	744	3.442e+40 17.6	1.131e+39 0.6	3.555e+40 18.2
65	Bu	751	760	760	752
66	Ag	760	763	761	760	1.485e+41 76.0	2.202e+39 1.1	1.508e+41 77.2
67	Bg	763	767	763	763	1.365e+38 0.1	2.137e+38 0.1	3.502e+38 0.2
68	Bu	774	779	774	779
69	Bg	779	779	779	779	5.195e+39 2.7	8.533e+39 4.4	1.373e+40 7.0
70	Au	779	782	782	782	5.296e+37 0.0	8.698e+37 0.0	1.399e+38 0.1
71	Ag	782	789	794	788	1.499e+40 7.7	9.386e+38 0.5	1.593e+40 8.2
72	Bu	794	797	807	817
73	Ag	817	817	817	821	8.854e+40 45.3	1.366e+40 7.0	1.022e+41 52.3
74	Au	834	834	837	834
75	Ag	837	837	838	837	1.102e+40 5.6	8.020e+39 4.1	1.904e+40 9.7
76	Bg	863	863	863	863	1.467e+39 0.8	1.966e+39 1.0	3.432e+39 1.8
77	Bu	877	880	877	889
78	Au	920	920	920	920
79	Bg	937	937	937	937	4.252e+38 0.2	5.409e+38 0.3	9.660e+38 0.5
80	Ag	947	947	947	947	2.671e+39 1.4	9.578e+38 0.5	3.629e+39 1.9
81	Au	962	962	987	962
82	Au	1013	1013	1024	1013
83	Bg	1024	1024	1029	1024	1.144e+39 0.6	1.550e+39 0.8	2.694e+39 1.4
84	Bu	1029	1029	1031	1040
85	Ag	1056	1056	1056	1056	5.610e+39 2.9	5.155e+39 2.6	1.077e+40 5.5
86	Bu	1065	1065	1065	1071
87	Ag	1084	1084	1084	1084	5.305e+39 2.7	2.604e+39 1.3	7.909e+39 4.0
88	Bg	1501	1501	1501	1501	1.576e+39 0.8	2.008e+39 1.0	3.584e+39 1.8
89	Bu	1507	1509	1507	1509
90	Bg	1587	1587	1587	1587	1.199e+38 0.1	1.293e+38 0.1	2.492e+38 0.1
91	Au	1599	1599	1601	1599
92	Ag	1602	1602	1602	1602	6.581e+38 0.3	2.394e+38 0.1	8.974e+38 0.5
93	Bu	1606	1614	1606	1606
94	Au	1621	1621	1621	1621
95	Ag	1636	1636	1636	1636	1.134e+39 0.6	7.706e+38 0.4	1.905e+39 1.0
96	Bg	2822	2822	2822	2822	9.183e+39 4.7	1.251e+40 6.4	2.169e+40 11.1
97	Au	2826	2826	2829	2826
98	Bu	2836	2855	2836	2855
99	Bg	2855	2856	2855	2858	2.267e+40 11.6	3.672e+40 18.8	5.938e+40 30.4
100	Ag	2858	2858	2858	2883	1.180e+41 60.4	7.734e+40 39.6	1.953e+41 100.0
101	Au	2883	2883	2904	2887
102	Ag	2928	2928	2928	2928	1.681e+41 86.0	1.269e+40 6.5	1.808e+41 92.5
103	Bu	2937	2990	2937	2973
104	Bg	3154	3154	3154	3154	1.744e+40 8.9	1.935e+40 9.9	3.678e+40 18.8
105	Au	3159	3159	3159	3159
106	Ag	3162	3162	3162	3162	1.574e+41 80.6	1.087e+40 5.6	1.683e+41 86.1
107	Bu	3165	3167	3165	3173
108	Bg	3217	3217	3217	3217	1.407e+40 7.2	2.228e+40 11.4	3.634e+40 18.6
109	Bu	3222	3223	3222	3223
110	Au	3223	3225	3239	3239
111	Ag	3239	3239	3275	3242	2.243e+40 11.5	1.201e+40 6.1	3.444e+40 17.6

No.

Char.

ω TO

ω LOx

ω LOy

ω LOz

I ∥

I ⊥