-    REALGAR     -    AsS

 

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/n 
Lattice parameters (Å):  9.3270  13.5630  6.5900 
Angles (°):  90.0  106.46  90.0 

Symmetry (theoretical): 

Space group:  14  P2_1/n 
Lattice parameters (Å):  9.3270  13.5630  6.5900 
Angles (°):  90  106.46  90 

Cell contents: 

Number of atoms:  32 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

As:  0.1724  0.9154  0.7913 
As:  0.3989  0.1301  0.8404 
As:  0.3247  0.0951  0.1799 
As:  0.0119  0.0729  0.7246 
S:  0.3795  0.9753  0.7132 
S:  0.2808  0.9318  0.1427 
S:  0.1726  0.1731  0.6267 
S:  0.0735  0.1302  0.0577 
As:  0.3276  0.4154  0.7087 
As:  0.1011  0.6301  0.6596 
As:  0.1753  0.5951  0.3201 
As:  0.4881  0.5729  0.7754 
S:  0.1205  0.4753  0.7868 
S:  0.2192  0.4318  0.3573 
S:  0.3274  0.6731  0.8733 
S:  0.4265  0.6302  0.4423 
As:  0.8276  0.0846  0.2087 
As:  0.6011  0.8699  0.1596 
As:  0.6753  0.9049  0.8201 
As:  0.9881  0.9271  0.2754 
S:  0.6205  0.0247  0.2868 
S:  0.7192  0.0682  0.8573 
S:  0.8274  0.8269  0.3733 
S:  0.9265  0.8698  0.9423 
As:  0.6724  0.5846  0.2913 
As:  0.8989  0.3699  0.3404 
As:  0.8247  0.4049  0.6799 
As:  0.5119  0.4271  0.2246 
S:  0.8795  0.5247  0.2132 
S:  0.7808  0.5682  0.6427 
S:  0.6726  0.3269  0.1267 
S:  0.5735  0.3698  0.5577 
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): 

As: 1.9174 0.3260 -0.2301 
-0.0587 1.6798 -0.0492 
-0.1147 0.1223 1.5335 
Eig. Value: 2.0213 1.6724 1.4369 
As: 1.6984 -0.4301 0.4843 
-0.0762 1.3773 0.0808 
0.0046 -0.0722 1.0304 
Eig. Value: 1.8913 1.2824 0.9323 
As: 2.5285 -0.0498 0.1359 
0.0587 2.0565 -0.1210 
0.0698 -0.1469 2.0858 
Eig. Value: 2.5525 1.9275 2.1908 
As: 1.8391 0.5120 -0.2203 
0.2858 1.4066 0.0016 
-0.0320 -0.1000 1.8669 
Eig. Value: 2.1417 1.1684 1.8026 
S: -3.1466 -0.1117 -0.1170 
-0.0054 -2.3560 0.2757 
0.0644 0.0355 -2.6566 
Eig. Value: -3.1514 -2.2852 -2.7226 
S: -0.7332 -0.0731 0.3815 
-0.2745 -0.4960 -0.0143 
0.1858 0.1484 -0.3868 
Eig. Value: -0.9650 -0.4266 -0.2244 
S: -4.6699 -0.1106 0.1994 
0.0570 -3.2825 -0.2163 
0.4559 0.1618 -3.6527 
Eig. Value: -4.7665 -3.2782 -3.5604 
S: -3.5008 -0.0539 0.3272 
-0.1847 -2.9661 0.2491 
-0.1376 0.2277 -2.9573 
Eig. Value: -3.5642 -3.1371 -2.7229 
As: 1.9812 -0.1168 -0.0695 
-0.1832 1.3786 0.0168 
0.1223 -0.0098 1.4695 
Eig. Value: 2.0176 1.3426 1.4691 
As: 0.1976 0.2308 0.2129 
0.0184 0.0369 0.1245 
0.3031 -0.0230 -0.0449 
Eig. Value: 0.4086 -0.0077 -0.2114 
As: 1.6204 0.1534 0.0010 
0.1964 0.8461 -0.1039 
-0.0407 0.1506 1.1116 
Eig. Value: 1.6585 0.8060 1.1136 
As: 1.6250 -0.4662 -0.3563 
-0.1035 1.2809 -0.0800 
-0.1795 -0.1559 1.4398 
Eig. Value: 1.8714 0.9874 1.4868 
S: 0.1581 -0.1607 -0.2535 
0.0829 -0.3034 0.0960 
-0.2090 0.2468 0.0906 
Eig. Value: 0.3880 -0.3721 -0.0705 
S: 0.4336 0.1622 -0.1701 
0.3668 0.0983 -0.0881 
-0.0866 -0.0309 0.3109 
Eig. Value: 0.6397 -0.0475 0.2506 
S: -1.9017 0.2826 -0.3118 
0.2113 -1.4912 -0.2914 
-0.2284 -0.1416 -1.5383 
Eig. Value: -2.0758 -1.7298 -1.1256 
S: 0.6890 0.0702 -0.0458 
-0.1394 1.1579 0.0616 
-0.1601 0.0774 1.2420 
Eig. Value: 0.6694 1.1196 1.2999 
As: 2.0008 0.1817 -0.2516 
0.1263 1.4205 -0.1600 
-0.0204 -0.0663 1.4827 
Eig. Value: 2.0820 1.3310 1.4909 
As: 2.0668 -0.4808 0.4365 
-0.1899 1.8929 -0.0917 
0.1112 0.0217 1.3062 
Eig. Value: 2.3803 1.6763 1.2093 
As: 2.3576 -0.1897 0.0762 
0.0530 1.8721 -0.2932 
0.1806 -0.1480 1.8637 
Eig. Value: 2.4184 2.0305 1.6444 
As: 2.0089 0.6214 -0.2991 
0.2982 1.5795 0.0967 
-0.1141 -0.1680 2.1480 
Eig. Value: 2.4348 1.2789 2.0228 
S: -3.8135 0.2201 -0.0759 
-0.1786 -3.2556 0.1174 
0.1758 0.1650 -3.3342 
Eig. Value: -3.8187 -3.1450 -3.4395 
S: -1.0459 -0.3653 0.4578 
-0.1736 -0.6804 -0.0377 
0.1485 -0.1679 -0.6563 
Eig. Value: -1.2769 -0.3338 -0.7718 
S: -4.0512 -0.3648 0.1408 
-0.0868 -3.1816 0.1837 
0.2343 0.1214 -3.6101 
Eig. Value: -4.1901 -3.1030 -3.5499 
S: -4.1873 -0.0651 0.4437 
-0.1851 -3.4098 0.2201 
-0.0428 0.0157 -3.5289 
Eig. Value: -4.2708 -3.3373 -3.5180 
As: 1.9669 -0.0572 -0.0996 
-0.1280 1.4858 -0.0058 
0.1395 0.0754 1.4247 
Eig. Value: 1.9844 1.4903 1.4027 
As: 0.8194 0.2987 -0.0658 
0.1333 0.4631 0.2370 
0.2913 -0.1147 0.3134 
Eig. Value: 0.9471 0.3619 0.2869 
As: 1.4799 0.0664 0.2334 
0.2452 1.0707 0.1514 
-0.0461 0.0610 1.0344 
Eig. Value: 1.5615 1.0807 0.9426 
As: 1.1756 -0.2898 -0.2166 
-0.1354 0.8752 -0.2267 
-0.1667 -0.1441 0.9219 
Eig. Value: 1.3121 0.5753 1.0854 
S: -1.1900 -0.0455 -0.1543 
0.0012 -0.8457 -0.0403 
-0.2364 -0.0311 -0.8002 
Eig. Value: -1.2738 -0.8476 -0.7145 
S: 1.3786 0.1195 -0.1764 
0.3240 1.0442 -0.0338 
-0.1061 0.0929 1.2291 
Eig. Value: 1.5332 0.9070 1.2117 
S: -2.1967 0.1796 -0.1678 
-0.1356 -1.5976 0.0069 
-0.2899 -0.1723 -1.7342 
Eig. Value: -2.2910 -1.5313 -1.7062 
S: 0.4943 0.0064 -0.2490 
-0.2196 0.8430 -0.0657 
-0.2761 -0.0308 0.9953 
Eig. Value: 0.3539 0.8710 1.1077 
Atom type 

Dielectric tensors: 

 
Ɛ6.1804 0.3772 0.4821 
0.3784 5.2981 0.9067 
0.4899 0.9068 4.3375 
Eig. Value: 6.6218 5.4243 3.7699 
Refractive index (N): 2.4860 0.6142 0.6943 
0.6152 2.3018 0.9522 
0.6999 0.9523 2.0827 
Eig. Value: 2.5733 2.3290 1.9416 
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