-    SUANITE     -    Mg2B2O5

 

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):  9.1970  3.1228  12.3030 
Angles (°):  90  104.26  90 

Symmetry (theoretical): 

Space group:  14  P2_1/c 
Lattice parameters (Å):  9.0676  3.0438  12.1636 
Angles (°):  90  104.30  90 

Cell contents: 

Number of atoms:  36 
Number of atom types:  3 
Chemical composition:  0 

Atomic positions (theoretical):

Mg:  0.1025  0.2129  0.1870 
Mg:  0.6470  0.2969  0.8948 
B:  0.3574  0.7708  0.3412 
B:  0.1691  0.3444  0.9400 
B:  0.4938  0.1936  0.1375 
B:  0.2577  0.7195  0.2385 
B:  0.1796  0.2165  0.0475 
B:  0.9466  0.7147  0.1527 
O:  0.3008  0.5759  0.9316 
O:  0.8975  0.7129  0.3130 
O:  0.3530  0.7969  0.6052 
O:  0.6426  0.2708  0.1588 
O:  0.8309  0.8444  0.5600 
O:  0.5062  0.6936  0.3625 
Mg:  0.7423  0.2195  0.2615 
Mg:  0.8204  0.7165  0.4525 
B:  0.0534  0.2147  0.3473 
B:  0.6992  0.0759  0.5684 
B:  0.8975  0.7871  0.8130 
B:  0.3530  0.7031  0.1052 
B:  0.6426  0.2292  0.6588 
B:  0.8309  0.6556  0.0600 
O:  0.5062  0.8064  0.8625 
O:  0.7423  0.2805  0.7615 
O:  0.8204  0.7835  0.9525 
O:  0.0534  0.2853  0.8473 
O:  0.6992  0.4241  0.0684 
O:  0.1025  0.2871  0.6870 
O:  0.6470  0.2031  0.3948 
Mg:  0.3574  0.7292  0.8412 
Mg:  0.1691  0.1556  0.4400 
Mg:  0.4938  0.3064  0.6375 
Mg:  0.2577  0.7805  0.7385 
Mg:  0.1796  0.2835  0.5475 
Mg:  0.9466  0.7853  0.6527 
Mg:  0.3008  0.9241  0.4316 
Atom type  X  Y  Z 

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): 

Mg: 2.1752 0.0030 0.0512 
0.0758 2.0067 -0.0319 
0.0664 -0.0068 2.1914 
Eig. Value: 2.1375 1.9925 2.2432 
Mg: 1.9901 -0.0185 0.1121 
-0.0247 2.0184 0.0631 
0.1839 0.0238 2.1777 
Eig. Value: 1.8955 2.0284 2.2624 
B: 2.6467 -0.4034 -0.0956 
-0.3632 1.2099 0.3805 
0.1755 0.3380 2.3921 
Eig. Value: 2.7509 1.0204 2.4773 
B: 2.1849 0.5843 0.2769 
0.6187 1.5709 -0.2019 
-0.0048 -0.3238 2.6234 
Eig. Value: 2.5500 1.1436 2.6856 
B: -2.2980 -0.1736 -0.2407 
-0.1933 -1.3562 -0.0167 
-0.2907 0.0139 -1.2719 
Eig. Value: -2.3935 -1.3385 -1.1941 
B: -1.5563 -0.0143 -0.2429 
-0.0467 -1.3140 -0.1347 
-0.3867 -0.1458 -2.1668 
Eig. Value: -1.4282 -1.2891 -2.3199 
B: -1.3824 -0.0739 0.1886 
-0.0628 -1.4307 0.2151 
0.1636 0.2967 -2.3280 
Eig. Value: -1.3340 -1.3775 -2.4295 
B: -1.7813 -0.1041 -0.5590 
-0.1317 -1.3324 -0.0901 
-0.4541 -0.0366 -1.9473 
Eig. Value: -1.3856 -1.2831 -2.3923 
O: -1.9788 -0.6150 0.5093 
-0.6088 -1.3726 0.2809 
0.5468 0.3066 -1.6706 
Eig. Value: -2.7094 -0.9909 -1.3217 
O: 2.1752 -0.0030 0.0512 
-0.0758 2.0067 0.0319 
0.0664 0.0068 2.1914 
Eig. Value: 2.1375 1.9925 2.2432 
O: 1.9901 0.0185 0.1121 
0.0247 2.0184 -0.0631 
0.1839 -0.0238 2.1777 
Eig. Value: 1.8955 2.0284 2.2624 
O: 2.6467 0.4034 -0.0956 
0.3632 1.2099 -0.3805 
0.1755 -0.3380 2.3921 
Eig. Value: 2.7509 1.0204 2.4773 
O: 2.1849 -0.5843 0.2769 
-0.6187 1.5709 0.2019 
-0.0048 0.3238 2.6234 
Eig. Value: 2.5500 1.1436 2.6856 
O: -2.2980 0.1736 -0.2407 
0.1933 -1.3562 0.0167 
-0.2907 -0.0139 -1.2719 
Eig. Value: -2.3935 -1.3385 -1.1941 
Mg: -1.5563 0.0143 -0.2429 
0.0467 -1.3140 0.1347 
-0.3867 0.1458 -2.1668 
Eig. Value: -1.4282 -1.2891 -2.3199 
Mg: -1.3824 0.0739 0.1886 
0.0628 -1.4307 -0.2151 
0.1636 -0.2967 -2.3280 
Eig. Value: -1.3340 -1.3775 -2.4295 
B: -1.7813 0.1041 -0.5590 
0.1317 -1.3324 0.0901 
-0.4541 0.0366 -1.9473 
Eig. Value: -1.3856 -1.2831 -2.3923 
B: -1.9788 0.6150 0.5093 
0.6088 -1.3726 -0.2809 
0.5468 -0.3066 -1.6706 
Eig. Value: -2.7094 -0.9909 -1.3217 
B: 2.1752 0.0030 0.0512 
0.0758 2.0067 -0.0319 
0.0664 -0.0068 2.1914 
Eig. Value: 2.1375 1.9925 2.2432 
B: 1.9901 -0.0185 0.1121 
-0.0247 2.0184 0.0631 
0.1839 0.0238 2.1777 
Eig. Value: 1.8955 2.0284 2.2624 
B: 2.6467 -0.4034 -0.0956 
-0.3632 1.2099 0.3805 
0.1755 0.3380 2.3921 
Eig. Value: 2.7509 1.0204 2.4773 
B: 2.1849 0.5843 0.2769 
0.6187 1.5709 -0.2019 
-0.0048 -0.3238 2.6234 
Eig. Value: 2.5500 1.1436 2.6856 
O: -2.2980 -0.1736 -0.2407 
-0.1933 -1.3562 -0.0167 
-0.2907 0.0139 -1.2719 
Eig. Value: -2.3935 -1.3385 -1.1941 
O: -1.5563 -0.0143 -0.2429 
-0.0467 -1.3140 -0.1347 
-0.3867 -0.1458 -2.1668 
Eig. Value: -1.4282 -1.2891 -2.3199 
O: -1.3824 -0.0739 0.1886 
-0.0628 -1.4307 0.2151 
0.1636 0.2967 -2.3280 
Eig. Value: -1.3340 -1.3775 -2.4295 
O: -1.7813 -0.1041 -0.5590 
-0.1317 -1.3324 -0.0901 
-0.4541 -0.0366 -1.9473 
Eig. Value: -1.3856 -1.2831 -2.3923 
O: -1.9788 -0.6150 0.5093 
-0.6088 -1.3726 0.2809 
0.5468 0.3066 -1.6706 
Eig. Value: -2.7094 -0.9909 -1.3217 
O: 2.1752 -0.0030 0.0512 
-0.0758 2.0067 0.0319 
0.0664 0.0068 2.1914 
Eig. Value: 2.1375 1.9925 2.2432 
O: 1.9901 0.0185 0.1121 
0.0247 2.0184 -0.0631 
0.1839 -0.0238 2.1777 
Eig. Value: 1.8955 2.0284 2.2624 
Mg: 2.6467 0.4034 -0.0956 
0.3632 1.2099 -0.3805 
0.1755 -0.3380 2.3921 
Eig. Value: 2.7509 1.0204 2.4773 
Mg: 2.1849 -0.5843 0.2769 
-0.6187 1.5709 0.2019 
-0.0048 0.3238 2.6234 
Eig. Value: 2.5500 1.1436 2.6856 
Mg: -2.2980 0.1736 -0.2407 
0.1933 -1.3562 0.0167 
-0.2907 -0.0139 -1.2719 
Eig. Value: -2.3935 -1.3385 -1.1941 
Mg: -1.5563 0.0143 -0.2429 
0.0467 -1.3140 0.1347 
-0.3867 0.1458 -2.1668 
Eig. Value: -1.4282 -1.2891 -2.3199 
Mg: -1.3824 0.0739 0.1886 
0.0628 -1.4307 -0.2151 
0.1636 -0.2967 -2.3280 
Eig. Value: -1.3340 -1.3775 -2.4295 
Mg: -1.7813 0.1041 -0.5590 
0.1317 -1.3324 0.0901 
-0.4541 0.0366 -1.9473 
Eig. Value: -1.3856 -1.2831 -2.3923 
Mg: -1.9788 0.6150 0.5093 
0.6088 -1.3726 -0.2809 
0.5468 -0.3066 -1.6706 
Eig. Value: -2.7094 -0.9909 -1.3217 
Atom type  X  Y  Z 

Dielectric tensors: 

 X Y Z 
Ɛ∞: 2.8600 0.0000 0.0198 
0.0000 2.6844 0.0000 
0.0198 0.0000 2.9016 
Eig. Value: 2.8521 2.6844 2.9095 
Refractive index (N): 1.6912 0.0000 0.1408 
0.0000 1.6384 0.0000 
0.1408 0.0000 1.7034 
Eig. Value: 1.6888 1.6384 1.7057 
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