- GUNNINGITE - ZnSO₄H₂O

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):	3.6646	4.0170		4.0403
Angles (°):	102.67	102.81		86.88

Symmetry (theoretical):

Space group:	15		C2/c
Lattice parameters (Å):	5.0819	5.0819		7.3782
Angles (°):	73.10	106.89		81.50

Cell contents:

Number of atoms:	18
Number of atom types:	4
Chemical composition:	0

Atomic positions (theoretical):

Zn:	0.5000	0.5000	0.0000
S:	0.1600	0.1600	0.2500
O:	0.2210	0.8850	0.4088
O:	0.3900	0.1564	0.1631
O:	0.6320	0.6320	0.2500
H:	0.8464	0.5674	0.2944
Zn:	0.5000	0.5000	0.5000
O:	0.8850	0.2210	0.0912
O:	0.1564	0.3900	0.3369
H:	0.5674	0.8464	0.2056
S:	0.8400	0.8400	0.7500
O:	0.7790	0.1150	0.5912
O:	0.6100	0.8436	0.8369
O:	0.3680	0.3680	0.7500
H:	0.1536	0.4326	0.7056
O:	0.1150	0.7790	0.9088
O:	0.8436	0.6100	0.6631
H:	0.4326	0.1536	0.7944

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.

Parameters of the Calculation

All the calculations have been done using the ABINIT software. This is a list of the most representative parameteres used during the Raman calculation.

Number of electronic bands:	26
k-points
grid:	6 6 4
number of shifts:	1
shifts:	0 0 0
Kinetic energy cut-off:	40 Ha [=1088.464 eV ]
eXchange-Correlation functional:	LDA_pw90

Pseudopotentials:
Zn:	zinc, fhi98PP : Trouiller-Martins-type, LDA Ceperley/Alder Perdew/Wang (1992), l= 0 local
S:	sulphur, fhi98PP : Trouiller-Martins-type, LDA Ceperley/Alder Perdew/Wang (1992), l= 2 local
O:	oxygen, fhi98PP : Trouiller-Martins-type, LDA Ceperley/Alder Perdew/Wang (1992), l= 2 local
H:	hydrogen, fhi98PP : Trouiller-Martins-type, LDA Ceperley/Alder Perdew/Wang (1992), l= 2 local

Dielectric Properties

We define:

The Born effective charges, also called dynamical charges, are tensors that correspond to the energy derivative with respect to atomic displacements and electric fields or, equivalently, to the change in atomic force due to an electric field: The sum of the Born effective charges of all nuclei in one cell must vanish, element by element, along each of the three directions of the space.
The dielectric tensors are the energy derivative with respect to two electric fields. They also relate the induced polarization to the external electric field.

Born effective charges (Z):

Zn:	2.3978	0.2412	-0.0712
	0.3173	2.5155	-0.1032
	0.3391	-0.0321	2.5095
Eig. Value:	2.1163	2.7471	2.5593
S:	3.8999	0.0000	0.5989
	-0.0000	3.5550	-0.0000
	-0.2470	0.0000	3.6679
Eig. Value:	3.9946	3.5550	3.5731
O:	-1.5642	0.4697	-0.7261
	0.4078	-1.3680	0.5863
	-0.5145	0.5420	-1.6126
Eig. Value:	-2.6153	-1.0298	-0.8997
O:	-2.0451	-0.4517	0.2336
	-0.3841	-1.6385	0.5114
	0.2934	0.5231	-1.2345
Eig. Value:	-2.5130	-1.5243	-0.8808
O:	-1.9761	0.0000	-0.0442
	-0.0000	-1.0207	0.0000
	0.0608	0.0000	-1.2919
Eig. Value:	-1.9762	-1.0207	-1.2918
H:	1.4485	0.4768	0.2507
	0.3538	0.4817	0.1045
	0.1447	0.0451	0.4044
Eig. Value:	1.6386	0.3277	0.3682
Zn:	2.3978	-0.2412	-0.0712
	-0.3173	2.5155	0.1032
	0.3391	0.0321	2.5095
Eig. Value:	2.1163	2.7471	2.5593
O:	-1.5642	-0.4697	-0.7261
	-0.4078	-1.3680	-0.5863
	-0.5145	-0.5420	-1.6126
Eig. Value:	-2.6153	-1.0298	-0.8997
O:	-2.0451	0.4517	0.2336
	0.3841	-1.6385	-0.5114
	0.2934	-0.5231	-1.2345
Eig. Value:	-2.5130	-1.5243	-0.8808
H:	1.4485	-0.4768	0.2507
	-0.3538	0.4817	-0.1045
	0.1447	-0.0451	0.4044
Eig. Value:	1.6386	0.3277	0.3682
S:	3.8999	-0.0000	0.5989
	-0.0000	3.5550	0.0000
	-0.2470	-0.0000	3.6679
Eig. Value:	3.9946	3.5550	3.5731
O:	-1.5642	0.4697	-0.7261
	0.4078	-1.3680	0.5863
	-0.5145	0.5420	-1.6126
Eig. Value:	-2.6153	-1.0298	-0.8997
O:	-2.0451	-0.4517	0.2336
	-0.3841	-1.6385	0.5114
	0.2934	0.5231	-1.2345
Eig. Value:	-2.5130	-1.5243	-0.8808
O:	-1.9761	0.0000	-0.0442
	-0.0000	-1.0207	0.0000
	0.0608	-0.0000	-1.2919
Eig. Value:	-1.9762	-1.0207	-1.2918
H:	1.4485	0.4768	0.2507
	0.3538	0.4817	0.1045
	0.1447	0.0451	0.4044
Eig. Value:	1.6386	0.3277	0.3682
O:	-1.5642	-0.4697	-0.7261
	-0.4078	-1.3680	-0.5863
	-0.5145	-0.5420	-1.6126
Eig. Value:	-2.6153	-1.0298	-0.8997
O:	-2.0451	0.4517	0.2336
	0.3841	-1.6385	-0.5114
	0.2934	-0.5231	-1.2345
Eig. Value:	-2.5130	-1.5243	-0.8808
H:	1.4485	-0.4768	0.2507
	-0.3538	0.4817	-0.1045
	0.1447	-0.0451	0.4044
Eig. Value:	1.6386	0.3277	0.3682

Atom type

Dielectric tensors:

	X	Y	Z
Ɛ_∞:	3.0566	0.0000	0.1036
	0.0000	2.8315	0.0000
	0.1036	0.0000	2.8244
Eig. Value:	3.0961	2.8315	2.7849
Refractive index (N):	1.7483	-0.0000	0.3218
	-0.0000	1.6827	-0.0000
	0.3218	-0.0000	1.6806
Eig. Value:	1.7596	1.6827	1.6688
Ɛ₀:	0.0000	0.0000	0.0000
	0.0000	0.0000	0.0000
	0.0000	0.0000	0.0000
Eig. Value:	0.0000	0.0000	0.0000

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	59	59	59	59	1.139e+38 0.1	1.304e+38 0.1	2.443e+38 0.1
5	Au	98	98	98	98
6	Bu	99	100	99	104
7	Bg	118	118	118	118	5.470e+37 0.0	7.522e+37 0.0	1.299e+38 0.1
8	Ag	128	128	128	128	1.854e+39 0.9	4.941e+38 0.3	2.348e+39 1.2
9	Bu	137	137	137	137
10	Bu	139	147	139	160
11	Au	174	174	174	174
12	Bg	186	186	186	186	2.818e+37 0.0	3.027e+37 0.0	5.845e+37 0.0
13	Au	187	187	213	187
14	Bu	213	214	226	228
15	Bg	228	228	228	239	1.669e+38 0.1	1.794e+38 0.1	3.463e+38 0.2
16	Ag	239	239	239	246	3.007e+40 15.4	1.169e+39 0.6	3.124e+40 16.0
17	Au	257	257	277	257
18	Bu	277	279	279	277
19	Bg	301	301	301	301	8.444e+39 4.3	1.306e+40 6.7	2.151e+40 11.0
20	Ag	305	305	305	305	2.309e+40 11.8	2.552e+39 1.3	2.564e+40 13.1
21	Bu	327	344	327	327
22	Au	344	364	350	344
23	Bu	376	378	376	378
24	Bg	378	401	378	386	1.603e+39 0.8	1.703e+39 0.9	3.306e+39 1.7
25	Ag	405	405	405	405	1.274e+40 6.5	4.494e+39 2.3	1.724e+40 8.8
26	Au	411	411	411	411
27	Ag	509	509	509	509	1.488e+40 7.6	1.349e+40 6.9	2.836e+40 14.5
28	Au	532	532	533	532
29	Bu	587	588	587	599
30	Bg	601	601	601	601	1.060e+40 5.4	1.612e+40 8.2	2.672e+40 13.6
31	Bu	604	606	604	604
32	Bg	606	609	606	606	5.621e+39 2.9	8.214e+39 4.2	1.383e+40 7.1
33	Au	609	613	613	609
34	Ag	613	650	620	613	9.447e+39 4.8	5.948e+39 3.0	1.540e+40 7.9
35	Bg	782	782	782	782	9.236e+38 0.5	1.035e+39 0.5	1.959e+39 1.0
36	Bu	785	801	785	798
37	Bu	953	980	953	980
38	Au	980	983	983	983
39	Ag	983	1023	988	985	1.913e+41 97.7	8.817e+38 0.5	1.922e+41 98.2
40	Bg	1023	1034	1023	1023	5.538e+39 2.8	6.370e+39 3.3	1.191e+40 6.1
41	Au	1034	1040	1034	1034
42	Bg	1045	1045	1045	1045	9.756e+39 5.0	1.619e+40 8.3	2.595e+40 13.3
43	Ag	1062	1062	1062	1062	2.482e+39 1.3	1.194e+39 0.6	3.676e+39 1.9
44	Bu	1081	1081	1081	1081
45	Ag	1081	1088	1081	1087	4.180e+40 21.3	1.561e+40 8.0	5.741e+40 29.3
46	Au	1106	1106	1165	1106
47	Bu	1165	1198	1181	1198
48	Bg	1198	1216	1198	1231	1.336e+40 6.8	1.428e+40 7.3	2.764e+40 14.1
49	Ag	1496	1496	1496	1496	5.736e+39 2.9	4.032e+39 2.1	9.768e+39 5.0
50	Au	1512	1512	1515	1512
51	Bu	2859	2865	2859	2865
52	Bg	2865	2904	2865	2865	2.276e+40 11.6	3.037e+40 15.5	5.313e+40 27.1
53	Ag	2904	2926	2904	2904	1.698e+41 86.7	2.602e+40 13.3	1.958e+41 100.0
54	Au	2926	2995	2954	2926

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.

Normalized

Raw

Options for intensity.

Single Crystal Raman spectra

Single crystal Raman spectrum

The Raman measurements performed on single crystals employ polarized lasers and allow for the selection of specific elements of the individual Raman tensors of the Raman-active modes.

By convention, in the following we assume a measurement as X(XZ)Z, i.e. incident laser polarized along the X axis, emergent light polarized along the Z axis. If the crystal is aligned with the xyz reference frame, we sample the α_xz element. As you rotate the crystal you can sample other entries of the Raman tensor or various linear combineations.