-    STRINGHAMITE     -    CaCuSiO4H2O

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/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):  0.5292  0.5292  0.5292 
Angles (°):  90  102  90 

Cell contents: 

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

Atomic positions (theoretical):

Ca:  0.6504  0.1766  0.3493 
Cu:  0.0000  1.0000  0.5000 
Cu:  0.5000  1.0000  0.0000 
Si:  0.9850  0.1111  0.9699 
O:  0.9102  0.2056  0.0315 
O:  0.8584  0.0872  0.6770 
O:  0.3173  0.1036  0.0342 
O:  0.8431  0.0526  0.1643 
O:  0.3598  0.2105  0.6408 
H:  0.3522  0.3315  0.2762 
H:  0.1734  0.2588  0.0980 
Ca:  0.3496  0.6766  0.1507 
Cu:  0.0000  0.5000  0.0000 
Cu:  0.5000  0.5000  0.5000 
Si:  0.0150  0.6111  0.5301 
O:  0.0898  0.7056  0.4685 
O:  0.1416  0.5872  0.8230 
O:  0.6827  0.6036  0.4658 
O:  0.1569  0.5526  0.3357 
O:  0.6402  0.7105  0.8592 
H:  0.6478  0.8315  0.2238 
H:  0.8266  0.7588  0.4020 
Ca:  0.3496  0.8234  0.6507 
Si:  0.0150  0.8889  0.0301 
O:  0.0898  0.7944  0.9685 
O:  0.1416  0.9128  0.3230 
O:  0.6827  0.8964  0.9658 
O:  0.1569  0.9474  0.8357 
O:  0.6402  0.7895  0.3592 
H:  0.6478  0.6685  0.7238 
H:  0.8266  0.7412  0.9020 
Ca:  0.6504  0.3234  0.8493 
Si:  0.9850  0.3889  0.4699 
O:  0.9102  0.2944  0.5315 
O:  0.8584  0.4128  0.1770 
O:  0.3173  0.3964  0.5342 
O:  0.8431  0.4474  0.6643 
O:  0.3598  0.2895  0.1408 
H:  0.3522  0.1685  0.7762 
H:  0.1734  0.2412  0.5980 
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: 

Size:

Nx:  Ny:  Nz: 
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: 2.4808 -0.4507 -0.0250 
-0.0417 2.4300 0.2706 
0.1180 -0.0370 2.4561 
Eig. Value: 2.7113 2.1603 2.4952 
Cu: 3.8443 1.0436 -9.6466 
-0.2904 1.7500 0.0348 
-4.7338 6.9810 8.1237 
Eig. Value: -2.8809 2.5520 14.0469 
Cu: 2.1764 8.6250 3.2946 
-0.2456 1.8962 0.2468 
1.3965 1.7650 1.2734 
Eig. Value: 7.2025 -2.4265 0.5700 
Si: 1.4628 -0.1755 0.6343 
-0.1710 2.7978 0.1710 
-1.3171 -0.5329 2.9629 
Eig. Value: 1.3585 2.7587 3.1063 
O: -2.4856 -3.0319 1.7113 
0.0980 -3.6318 -0.2152 
0.2024 -0.9736 -1.8009 
Eig. Value: -0.5056 -4.6346 -2.7781 
O: -1.1183 0.5212 1.3500 
0.1550 -1.7160 -0.3336 
0.4717 -0.1233 -3.3459 
Eig. Value: -0.7317 -1.7232 -3.7253 
O: -3.1284 0.8533 1.9416 
0.3805 -2.3524 0.1368 
0.0939 -0.0149 -1.0123 
Eig. Value: -3.7573 -2.1820 -0.5537 
O: 3.4584 8.5670 1.2963 
-0.5553 -1.3610 0.2839 
1.1806 2.3387 -2.9534 
Eig. Value: 6.0543 -4.0051 -2.9052 
O: -2.0971 -1.2248 1.4097 
0.4899 -2.5793 0.4905 
-0.0606 -0.1268 -1.4784 
Eig. Value: -2.1473 -2.9633 -1.0442 
H: 0.3871 -0.5279 -0.1422 
-0.1877 0.7858 0.6145 
-0.1417 0.4499 0.8663 
Eig. Value: 0.1250 0.4409 1.4733 
H: 0.9818 0.3035 0.3142 
1.0064 1.0169 0.3160 
0.3951 0.3401 0.4137 
Eig. Value: 0.3497 1.8201 0.2425 
Ca: 2.1627 0.1939 -0.1230 
0.0508 2.6910 -0.2947 
0.0827 -0.0822 2.5046 
Eig. Value: 2.1344 2.8279 2.3960 
Cu: 3.1239 -9.3003 -28.4194 
0.8599 1.1757 -0.6840 
-0.9554 -1.4240 4.0972 
Eig. Value: -12.1609 1.9719 18.5859 
Cu: 5.8811 -6.9017 3.5695 
0.5185 1.3504 -0.1554 
0.3597 -1.4237 0.4057 
Eig. Value: 8.1069 -0.4380 -0.0317 
Si: 2.9630 -0.5984 -0.0338 
0.1597 3.2163 -0.0055 
-0.6148 0.0179 2.7397 
Eig. Value: 3.0356 3.3969 2.4865 
O: -2.7650 1.3686 1.6455 
-0.1650 -2.1839 0.3017 
0.2098 0.1688 -1.7917 
Eig. Value: -3.4595 -2.2848 -0.9963 
O: -3.7364 -2.8833 2.3792 
-0.2667 -1.1634 0.1773 
0.2052 -0.8682 -2.4466 
Eig. Value: -4.9317 -0.0666 -2.3481 
O: -1.1837 1.1423 1.4586 
-0.1180 -1.1048 -0.2257 
0.5444 0.2119 -1.2204 
Eig. Value: -0.0671 -1.1232 -2.3186 
O: -4.9665 -0.7047 -0.4637 
-0.0314 -0.9369 -0.1560 
-0.2526 -1.7297 -3.3622 
Eig. Value: -5.1243 -0.6010 -3.5403 
O: -1.8496 0.3269 1.5021 
-0.4058 -1.2614 -0.4600 
0.0211 -0.5441 -1.3901 
Eig. Value: -2.4800 -1.4683 -0.5528 
H: 0.3896 0.3533 0.0745 
0.1875 0.9615 -0.6051 
-0.1383 -0.5155 0.9434 
Eig. Value: 0.2052 1.5534 0.5359 
H: 1.0291 -0.3687 0.2757 
-0.9585 1.1929 -0.3095 
0.3988 -0.3578 0.4218 
Eig. Value: 0.4475 1.9284 0.2678 
Ca: 2.2159 0.3444 -0.3547 
-0.0382 2.7131 0.2891 
-0.0070 -0.2467 2.1704 
Eig. Value: 2.3502 2.7580 1.9911 
Si: 2.7049 1.0155 1.7898 
-0.2140 3.3195 0.0956 
-0.5347 -0.5268 3.8734 
Eig. Value: 2.2409 3.5083 4.1486 
O: -2.4470 -0.9821 1.7089 
0.0767 -2.1483 -0.1878 
0.0782 -0.6398 -1.8861 
Eig. Value: -3.1215 -2.4288 -0.9312 
O: -2.9528 3.6232 2.6624 
0.0575 -0.7121 -0.3568 
0.0375 -0.0486 -3.2690 
Eig. Value: -4.9700 0.3935 -2.3574 
O: -1.7503 0.3801 1.5553 
0.1963 -0.9902 0.1965 
0.2644 -0.3645 -1.1271 
Eig. Value: -2.4554 -0.9553 -0.4569 
O: 0.7559 9.2839 -2.0232 
-0.2672 -0.6159 0.4199 
1.1336 2.4982 -2.8973 
Eig. Value: 4.6813 -5.3110 -2.1276 
O: -1.9747 1.1358 1.4621 
0.4746 -1.1808 0.4205 
-0.0713 0.1862 -1.5559 
Eig. Value: -2.6758 -0.3356 -1.7000 
H: 0.4239 -0.1012 0.0211 
-0.1800 0.9526 0.6205 
-0.0900 0.3408 0.7478 
Eig. Value: 0.4476 1.3600 0.3167 
H: 1.0697 0.5967 0.3245 
0.9577 1.1748 0.3068 
0.2707 0.1599 0.3870 
Eig. Value: 0.3821 1.9885 0.2609 
Ca: 2.2869 -0.5224 0.0887 
0.0668 2.4157 -0.2578 
0.0868 0.1815 2.4046 
Eig. Value: 2.1068 2.6209 2.3796 
Si: 2.7330 -1.9567 -0.6456 
0.0888 2.7216 -0.1308 
-0.3693 0.1444 3.0153 
Eig. Value: 3.8363 1.6939 2.9396 
O: -2.8658 -1.1505 1.6374 
-0.1888 -3.6956 0.3229 
0.1100 -0.2699 -1.8814 
Eig. Value: -2.9459 -4.1713 -1.3257 
O: -2.0317 -1.9774 0.1449 
-0.2213 -1.9433 0.0280 
0.5093 -0.3927 -2.9989 
Eig. Value: -3.1820 -0.8280 -2.9638 
O: -3.0668 -2.9426 2.0080 
-0.3872 -2.5322 -0.1042 
-0.1822 -1.0114 -1.2559 
Eig. Value: -4.5231 -0.1535 -2.1783 
O: -1.4367 -1.5768 4.2022 
0.3619 -1.6320 0.2284 
1.1733 -2.1369 -1.6153 
Eig. Value: 1.5455 -1.9852 -4.2443 
O: -2.0099 -1.5949 1.2639 
-0.4329 -2.6376 -0.5558 
-0.0596 -0.8032 -1.5801 
Eig. Value: -0.5141 -3.4096 -2.3038 
H: 0.3744 0.1101 -0.1384 
0.1941 0.7915 -0.6120 
-0.0777 -0.3579 0.6778 
Eig. Value: 0.3399 1.2617 0.2421 
H: 0.9608 -0.8155 0.2889 
-1.0138 1.0257 -0.3219 
0.2623 -0.2321 0.3842 
Eig. Value: 0.0778 2.0028 0.2901 
Atom type 

Dielectric tensors: 

 
Ɛ15.8039 0.0000 14.3562 
0.0794 3.7594 0.0000 
12.4785 0.0000 25.6417 
Eig. Value: 6.4325 3.7591 35.0134 
Refractive index (N): 3.9754 0.0000 3.7890 
0.2818 1.9389 0.0000 
3.5325 0.0000 5.0638 
Eig. Value: 2.5362 1.9388 5.9172 
Ɛ00.0000 0.0000 0.0000 
0.0000 0.0000 0.0000 
0.0000 0.0000 0.0000 
Eig. Value: 0.0000 0.0000 0.0000