- STRINGHAMITE - CaCuSiO₄H₂O

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:	14		P2_1/c
Lattice parameters (Å):	5.0300	16.1350		5.3430
Angles (°):	90	102.96		90

Symmetry (theoretical):

Space group:	14		P2_1/c
Lattice parameters (Å):	5.0308	15.9823		5.3582
Angles (°):	90	101.22		90

Cell contents:

Number of atoms:	40
Number of atom types:	5
Chemical composition:	0

Atomic positions (theoretical):

Ca:	0.6495	0.1764	0.3533
Cu:	0.0000	0.0000	0.5000
Cu:	0.5000	0.0000	1.0000
Si:	0.9860	0.1112	0.9733
O:	0.9109	0.2060	0.0352
O:	0.8618	0.0876	0.6799
O:	0.3158	0.1035	0.0379
O:	0.8408	0.0524	0.1668
O:	0.3603	0.2108	0.6470
H:	0.3519	0.3314	0.2832
H:	0.1747	0.2592	0.1036
Ca:	0.3505	0.6764	0.1467
Cu:	0.0000	0.5000	1.0000
Cu:	0.5000	0.5000	0.5000
Si:	0.0140	0.6112	0.5267
O:	0.0891	0.7060	0.4648
O:	0.1382	0.5876	0.8201
O:	0.6842	0.6035	0.4621
O:	0.1592	0.5524	0.3332
O:	0.6397	0.7108	0.8530
H:	0.6481	0.8314	0.2168
H:	0.8253	0.7592	0.3964
Ca:	0.3505	0.8236	0.6467
Si:	0.0140	0.8888	0.0267
O:	0.0891	0.7940	0.9648
O:	0.1382	0.9124	0.3201
O:	0.6842	0.8965	0.9621
O:	0.1592	0.9476	0.8332
O:	0.6397	0.7892	0.3530
H:	0.6481	0.6686	0.7168
H:	0.8253	0.7408	0.8964
Ca:	0.6495	0.3236	0.8533
Si:	0.9860	0.3888	0.4733
O:	0.9109	0.2940	0.5352
O:	0.8618	0.4124	0.1799
O:	0.3158	0.3965	0.5379
O:	0.8408	0.4476	0.6668
O:	0.3603	0.2892	0.1470
H:	0.3519	0.1686	0.7832
H:	0.1747	0.2408	0.6036

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.

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):

Ca:	2.1978	-0.2900	0.1422
	-0.0659	2.5480	0.2515
	0.4446	-0.1528	2.0142
Eig. Value:	2.3566	2.6327	1.7707
Cu:	0.9864	-1.2989	-0.0451
	-0.4140	1.1776	0.1175
	-4.8465	5.5410	0.2051
Eig. Value:	4.9138	0.2208	-2.7655
Cu:	-0.3621	-0.0249	0.3107
	-0.1585	1.4662	0.1929
	5.7920	8.7072	5.3461
Eig. Value:	-2.9528	0.4483	8.9547
Si:	3.1290	-0.1976	-0.7557
	-0.0523	3.0492	0.1748
	-3.8397	-1.1485	5.6372
Eig. Value:	1.6719	3.1110	7.0326
O:	-1.7269	-1.9206	0.0526
	0.1267	-2.6622	-0.3021
	-0.6862	-0.1080	-1.1722
Eig. Value:	-1.3155	-3.2617	-0.9841
O:	-0.9305	-0.8327	-0.1091
	0.1649	-1.4094	-0.2974
	0.6632	2.5541	-2.8134
Eig. Value:	-0.9857	-0.6635	-3.5041
O:	-1.7374	-1.0484	-0.0039
	0.1877	-1.4707	0.1787
	-1.2745	1.8786	0.7388
Eig. Value:	-2.0622	-1.7357	1.3287
O:	-1.5114	-1.6790	-0.0001
	-0.3124	-1.2086	0.2821
	6.3069	15.1488	-5.9352
Eig. Value:	-0.8241	4.7029	-12.5340
O:	-1.3884	-0.6698	-0.3071
	0.4410	-1.6934	0.4634
	-0.4527	-0.2489	-0.9610
Eig. Value:	-1.5947	-1.7324	-0.7157
H:	0.4322	-0.2500	0.4027
	-0.1868	0.8878	0.6040
	-0.1755	0.1590	-0.6284
Eig. Value:	0.3959	1.0371	-0.7414
H:	1.1033	0.2148	0.3406
	0.9453	1.0777	0.3161
	0.1962	0.7523	0.2837
Eig. Value:	1.8752	0.5750	0.0146
Ca:	2.5380	0.4015	0.9716
	0.0633	2.5814	-0.2682
	-1.1049	-1.0797	0.0846
Eig. Value:	2.3806	2.9090	-0.0857
Cu:	2.6196	1.6007	-1.7575
	0.3533	1.0916	-0.1533
	-3.4992	-6.4523	12.6422
Eig. Value:	1.9852	0.1749	14.1933
Cu:	2.8697	-0.7999	-0.5174
	0.1122	1.0693	-0.1004
	-3.7745	0.7065	1.4994
Eig. Value:	4.4980	1.0101	-0.0697
Si:	2.2287	-0.0502	-4.0956
	0.0678	3.1107	-0.1363
	3.2240	-1.6387	11.5360
Eig. Value:	2.2070	3.0199	11.6485
O:	-2.0446	-0.1255	-0.2055
	-0.1281	-2.8454	0.2830
	0.5487	-0.2774	-0.9836
Eig. Value:	-2.0517	-2.8655	-0.9564
O:	3.7333	6.0280	-5.0845
	-0.1630	-1.5272	0.2920
	-10.7806	-14.0078	8.2178
Eig. Value:	-1.3533	-5.2857	17.0630
O:	-5.1029	-5.6207	0.0764
	-0.2010	-1.5911	-0.1787
	6.4046	11.5952	-1.4874
Eig. Value:	-1.7032	-10.6558	4.1777
O:	4.0511	6.8236	13.8831
	0.3858	-1.3952	-0.2944
	-12.4606	-16.2250	-31.4259
Eig. Value:	6.1427	-1.2976	-33.6151
O:	-1.4907	0.7887	-0.9155
	-0.4371	-1.8473	-0.4860
	-0.1120	-3.3093	0.6940
Eig. Value:	-1.5724	-2.8662	1.7946
H:	0.3859	0.2858	-0.1360
	0.1943	0.8964	-0.6222
	-0.0940	-0.6113	0.8610
Eig. Value:	0.3863	1.5506	0.2064
H:	0.9286	-0.5576	0.3164
	-0.9628	1.0856	-0.3246
	0.5582	-0.2061	0.3223
Eig. Value:	0.3517	1.9226	0.0623
Ca:	2.2148	0.2428	0.0189
	-0.0744	2.5738	0.2569
	0.2582	-0.7774	2.2374
Eig. Value:	1.9827	2.7156	2.3277
Si:	3.2406	0.7895	-0.6365
	-0.0595	3.0711	0.1789
	-3.6419	-2.5263	5.7763
Eig. Value:	1.9395	2.8143	7.3342
O:	-1.7998	0.8106	0.1085
	0.1220	-2.8380	-0.3042
	-0.5107	-4.8122	-1.3653
Eig. Value:	-1.8584	-4.7851	0.6405
O:	-1.2599	0.3696	0.1533
	0.1679	-1.4664	-0.2963
	0.3262	1.7876	-2.3818
Eig. Value:	-1.5185	-0.7863	-2.8032
O:	-1.7571	0.2989	0.0208
	0.2132	-1.5749	0.1733
	-0.8390	-0.6118	0.6609
Eig. Value:	-1.9565	-1.4716	0.7570
O:	-1.5804	-0.8369	-0.2929
	-0.3450	-1.2792	0.2629
	5.5055	14.2030	-7.0100
Eig. Value:	-1.2002	3.8252	-12.4946
O:	-1.3936	-0.0887	0.1475
	0.4438	-1.8355	0.4819
	-0.3972	0.1483	-1.9572
Eig. Value:	-1.3307	-1.5879	-2.2677
H:	0.3563	-0.2844	-0.7731
	-0.1959	0.9042	0.6297
	-0.1230	0.5883	2.4127
Eig. Value:	0.2375	0.7015	2.7342
H:	0.9168	0.7381	0.2050
	0.9751	1.0913	0.3251
	0.6614	-0.2058	0.5992
Eig. Value:	-0.0031	1.9507	0.6597
Ca:	1.5203	-0.6648	-0.6805
	0.0638	2.5417	-0.2582
	1.5641	1.3110	4.4150
Eig. Value:	1.3309	2.5522	4.5939
Si:	6.3613	-2.2437	1.1748
	0.0461	3.0428	-0.1540
	-8.2084	3.6066	-2.6490
Eig. Value:	8.0928	2.7563	-4.0940
O:	-1.3851	-2.0476	0.5630
	-0.1226	-2.6753	0.3056
	-1.2596	2.1728	-2.7305
Eig. Value:	-0.3658	-4.0568	-2.3683
O:	-6.4816	-5.7477	5.3987
	-0.1455	-1.4068	0.2739
	11.9475	8.2895	-14.5884
Eig. Value:	-0.9963	-0.0261	-21.4544
O:	2.2574	5.0634	-0.1971
	-0.1791	-1.4899	-0.1799
	-8.9853	-12.9916	-1.1318
Eig. Value:	-1.2473	-8.1458	9.0288
O:	-12.3424	5.1633	-8.6179
	0.3201	-1.3306	-0.3008
	23.2260	-12.0534	14.8183
Eig. Value:	-15.4898	-1.5169	18.1520
O:	-1.2164	-1.8232	0.7952
	-0.4313	-1.6876	-0.4637
	-0.7104	1.1738	-3.1814
Eig. Value:	-0.2876	-2.4769	-3.3209
H:	0.3874	0.0641	-0.2062
	0.1886	0.8893	-0.6070
	-0.1100	-0.3219	0.9377
Eig. Value:	0.3452	0.4512	1.4181
H:	1.0523	-0.5804	0.2551
	-0.9476	1.0792	-0.3165
	0.2592	-0.5574	0.4626
Eig. Value:	0.1855	1.9893	0.4193