-    CLINOENSTATITE     -    Mg2Si2O6

 

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):  9.6200  8.8250  5.1880 
Angles (°):  90.0  71.7  90.0 

Symmetry (theoretical): 

Space group:  14  P2_1/c 
Lattice parameters (Å):  9.4479  8.6502  5.0862 
Angles (°):  90.0  72.0  90.0 

Cell contents: 

Number of atoms:  40 
Number of atom types:  3 
Chemical composition:  0 

Atomic positions (theoretical):

Mg:  0.2485  0.3448  0.2139 
Mg:  0.2432  0.9862  0.2110 
Si:  0.4570  0.6580  0.2969 
Si:  0.0547  0.6624  0.2744 
O:  0.3653  0.1603  0.3117 
O:  0.1237  0.1613  0.1203 
O:  0.3767  0.4971  0.3193 
O:  0.1346  0.5169  0.1083 
O:  0.3929  0.7835  0.1210 
O:  0.1077  0.8099  0.0543 
Mg:  0.7515  0.8448  0.2861 
Mg:  0.7568  0.4862  0.2890 
Si:  0.5430  0.1580  0.2031 
Si:  0.9453  0.1624  0.2256 
O:  0.6347  0.6603  0.1883 
O:  0.8763  0.6613  0.3797 
O:  0.6233  0.9971  0.1807 
O:  0.8654  0.0169  0.3917 
O:  0.6071  0.2835  0.3790 
O:  0.8923  0.3099  0.4457 
Mg:  0.7515  0.6552  0.7861 
Mg:  0.7568  0.0138  0.7890 
Si:  0.5430  0.3420  0.7031 
Si:  0.9453  0.3376  0.7256 
O:  0.6347  0.8397  0.6883 
O:  0.8763  0.8387  0.8797 
O:  0.6233  0.5029  0.6807 
O:  0.8654  0.4831  0.8917 
O:  0.6071  0.2165  0.8790 
O:  0.8923  0.1901  0.9457 
Mg:  0.2485  0.1552  0.7139 
Mg:  0.2432  0.5138  0.7110 
Si:  0.4570  0.8420  0.7969 
Si:  0.0547  0.8376  0.7744 
O:  0.3653  0.3397  0.8117 
O:  0.1237  0.3387  0.6203 
O:  0.3767  0.0029  0.8193 
O:  0.1346  0.9831  0.6083 
O:  0.3929  0.7165  0.6210 
O:  0.1077  0.6901  0.5543 
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: 2.1422 0.0083 -0.0693 
0.0203 2.1381 0.0200 
-0.0580 0.0320 1.9875 
Eig. Value: 2.1659 2.1420 1.9599 
Mg: 2.1662 0.0247 -0.0675 
0.0219 2.0894 0.0588 
-0.0693 0.0938 2.0226 
Eig. Value: 2.1942 2.1341 1.9499 
Si: 3.0444 0.0429 0.0788 
-0.0599 3.1081 -0.0413 
0.0826 -0.2587 3.3067 
Eig. Value: 2.9980 3.0581 3.4031 
Si: 2.9885 -0.1455 0.0711 
0.0845 2.9617 0.0563 
0.0641 -0.1465 3.4250 
Eig. Value: 2.9931 2.9418 3.4403 
O: -2.0968 0.0075 0.2019 
-0.0727 -1.5255 0.0084 
0.2036 -0.0511 -1.6048 
Eig. Value: -2.1704 -1.4970 -1.5596 
O: -2.1310 -0.0114 0.2241 
0.0956 -1.5367 -0.0433 
0.2177 -0.0481 -1.6004 
Eig. Value: -2.2155 -1.5555 -1.4972 
O: -1.6159 -0.3296 0.0230 
-0.3411 -1.9607 0.0338 
0.0239 0.0132 -1.5013 
Eig. Value: -1.4105 -2.1669 -1.5004 
O: -1.4676 0.2812 0.1098 
0.2509 -1.8614 -0.2725 
0.1095 -0.1686 -1.7050 
Eig. Value: -1.3335 -2.1362 -1.5643 
O: -1.4951 0.3972 -0.1951 
0.3216 -1.7174 0.5422 
-0.2125 0.6240 -2.1577 
Eig. Value: -1.1707 -1.5196 -2.6800 
O: -1.5348 -0.0128 -0.3768 
0.0086 -1.6955 0.5097 
-0.3615 0.5189 -2.1727 
Eig. Value: -1.2080 -1.6003 -2.5947 
Mg: 2.1422 -0.0083 -0.0693 
-0.0203 2.1381 -0.0200 
-0.0580 -0.0320 1.9875 
Eig. Value: 2.1659 2.1420 1.9599 
Mg: 2.1662 -0.0247 -0.0675 
-0.0219 2.0894 -0.0588 
-0.0693 -0.0938 2.0226 
Eig. Value: 2.1942 2.1341 1.9499 
Si: 3.0444 -0.0429 0.0788 
0.0599 3.1081 0.0413 
0.0826 0.2587 3.3067 
Eig. Value: 2.9980 3.0581 3.4031 
Si: 2.9885 0.1455 0.0711 
-0.0845 2.9617 -0.0563 
0.0641 0.1465 3.4250 
Eig. Value: 2.9931 2.9418 3.4403 
O: -2.0968 -0.0075 0.2019 
0.0727 -1.5255 -0.0084 
0.2036 0.0511 -1.6048 
Eig. Value: -2.1704 -1.4970 -1.5596 
O: -2.1310 0.0114 0.2241 
-0.0956 -1.5367 0.0433 
0.2177 0.0481 -1.6004 
Eig. Value: -2.2155 -1.5555 -1.4972 
O: -1.6159 0.3296 0.0230 
0.3411 -1.9607 -0.0338 
0.0239 -0.0132 -1.5013 
Eig. Value: -1.4105 -2.1669 -1.5004 
O: -1.4676 -0.2812 0.1098 
-0.2509 -1.8614 0.2725 
0.1095 0.1686 -1.7050 
Eig. Value: -1.3335 -2.1362 -1.5643 
O: -1.4951 -0.3972 -0.1951 
-0.3216 -1.7174 -0.5422 
-0.2125 -0.6240 -2.1577 
Eig. Value: -1.1707 -1.5196 -2.6800 
O: -1.5348 0.0128 -0.3768 
-0.0086 -1.6955 -0.5097 
-0.3615 -0.5189 -2.1727 
Eig. Value: -1.2080 -1.6003 -2.5947 
Mg: 2.1422 0.0083 -0.0693 
0.0203 2.1381 0.0200 
-0.0580 0.0320 1.9875 
Eig. Value: 2.1659 2.1420 1.9599 
Mg: 2.1662 0.0247 -0.0675 
0.0219 2.0894 0.0588 
-0.0693 0.0938 2.0226 
Eig. Value: 2.1942 2.1341 1.9499 
Si: 3.0444 0.0429 0.0788 
-0.0599 3.1081 -0.0413 
0.0826 -0.2587 3.3067 
Eig. Value: 2.9980 3.0581 3.4031 
Si: 2.9885 -0.1455 0.0711 
0.0845 2.9617 0.0563 
0.0641 -0.1465 3.4250 
Eig. Value: 2.9931 2.9418 3.4403 
O: -2.0968 0.0075 0.2019 
-0.0727 -1.5255 0.0084 
0.2036 -0.0511 -1.6048 
Eig. Value: -2.1704 -1.4970 -1.5596 
O: -2.1310 -0.0114 0.2241 
0.0956 -1.5367 -0.0433 
0.2177 -0.0481 -1.6004 
Eig. Value: -2.2155 -1.5555 -1.4972 
O: -1.6159 -0.3296 0.0230 
-0.3411 -1.9607 0.0338 
0.0239 0.0132 -1.5013 
Eig. Value: -1.4105 -2.1669 -1.5004 
O: -1.4676 0.2812 0.1098 
0.2509 -1.8614 -0.2725 
0.1095 -0.1686 -1.7050 
Eig. Value: -1.3335 -2.1362 -1.5643 
O: -1.4951 0.3972 -0.1951 
0.3216 -1.7174 0.5422 
-0.2125 0.6240 -2.1577 
Eig. Value: -1.1707 -1.5196 -2.6800 
O: -1.5348 -0.0128 -0.3768 
0.0086 -1.6955 0.5097 
-0.3615 0.5189 -2.1727 
Eig. Value: -1.2080 -1.6003 -2.5947 
Mg: 2.1422 -0.0083 -0.0693 
-0.0203 2.1381 -0.0200 
-0.0580 -0.0320 1.9875 
Eig. Value: 2.1659 2.1420 1.9599 
Mg: 2.1662 -0.0247 -0.0675 
-0.0219 2.0894 -0.0588 
-0.0693 -0.0938 2.0226 
Eig. Value: 2.1942 2.1341 1.9499 
Si: 3.0444 -0.0429 0.0788 
0.0599 3.1081 0.0413 
0.0826 0.2587 3.3067 
Eig. Value: 2.9980 3.0581 3.4031 
Si: 2.9885 0.1455 0.0711 
-0.0845 2.9617 -0.0563 
0.0641 0.1465 3.4250 
Eig. Value: 2.9931 2.9418 3.4403 
O: -2.0968 -0.0075 0.2019 
0.0727 -1.5255 -0.0084 
0.2036 0.0511 -1.6048 
Eig. Value: -2.1704 -1.4970 -1.5596 
O: -2.1310 0.0114 0.2241 
-0.0956 -1.5367 0.0433 
0.2177 0.0481 -1.6004 
Eig. Value: -2.2155 -1.5555 -1.4972 
O: -1.6159 0.3296 0.0230 
0.3411 -1.9607 -0.0338 
0.0239 -0.0132 -1.5013 
Eig. Value: -1.4105 -2.1669 -1.5004 
O: -1.4676 -0.2812 0.1098 
-0.2509 -1.8614 0.2725 
0.1095 0.1686 -1.7050 
Eig. Value: -1.3335 -2.1362 -1.5643 
O: -1.4951 -0.3972 -0.1951 
-0.3216 -1.7174 -0.5422 
-0.2125 -0.6240 -2.1577 
Eig. Value: -1.1707 -1.5196 -2.6800 
O: -1.5348 0.0128 -0.3768 
-0.0086 -1.6955 -0.5097 
-0.3615 -0.5189 -2.1727 
Eig. Value: -1.2080 -1.6003 -2.5947 
Atom type  X  Y  Z 

Dielectric tensors: 

 X Y Z 
Ɛ∞: 2.8446 0.0000 0.0000 
0.0000 2.8480 0.0000 
0.0000 0.0000 2.8751 
Eig. Value: 2.8446 2.8480 2.8751 
Refractive index (N): 1.6866 0.0000 0.0000 
0.0000 1.6876 0.0000 
0.0000 0.0000 1.6956 
Eig. Value: 1.6866 1.6876 1.6956 
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 
 

Available spectra for CLINOENSTATITE



1 spectra available in the database:

ID: CalcCond: Comment:
w000075  TheoStr