-    Na2Mg(SO4)2     -    Na2Mg(SO4)2

 

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:  15  C2/c 
Lattice parameters (Å):  10.1010  8.2400  8.7300 
Angles (°):  90.0  114.640  90.0 

Symmetry (theoretical): 

Space group:  15  C2/c 
Lattice parameters (Å):  6.2840  6.2840  8.6606 
Angles (°):  67.88  112.11  101.71 

Cell contents: 

Number of atoms:  26 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Mg:  0.0933  0.0933  0.2500 
Na:  0.3968  0.6686  0.0591 
S:  0.6083  0.9833  0.3171 
O:  0.7501  0.0269  0.4826 
O:  0.4114  0.1295  0.2304 
O:  0.5270  0.7398  0.3485 
O:  0.7445  0.0518  0.1980 
Na:  0.6686  0.3968  0.4409 
S:  0.9833  0.6083  0.1829 
O:  0.0269  0.7501  0.0174 
O:  0.1295  0.4114  0.2696 
O:  0.7398  0.5270  0.1515 
O:  0.0518  0.7445  0.3020 
Mg:  0.9067  0.9067  0.7500 
Na:  0.6032  0.3314  0.9409 
S:  0.3917  0.0167  0.6829 
O:  0.2499  0.9731  0.5174 
O:  0.5886  0.8705  0.7696 
O:  0.4730  0.2602  0.6515 
O:  0.2555  0.9482  0.8020 
Na:  0.3314  0.6032  0.5591 
S:  0.0167  0.3917  0.8171 
O:  0.9731  0.2499  0.9826 
O:  0.8705  0.5886  0.7304 
O:  0.2602  0.4730  0.8485 
O:  0.9482  0.2555  0.6980 
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): 

Mg: 2.2890 -0.1002 0.0170 
-0.1002 2.2471 -0.0138 
0.0863 -0.0701 2.2706 
Eig. Value: 2.4037 2.1657 2.2373 
Na: 1.1271 0.0413 0.0414 
0.0586 1.0632 0.1236 
-0.0322 0.0371 1.0947 
Eig. Value: 1.1124 0.9875 1.1851 
S: 3.5435 -0.0153 -0.0969 
0.0189 3.3292 -0.0586 
-0.0361 0.0973 3.4255 
Eig. Value: 3.5736 3.3242 3.4003 
O: -1.0332 -0.0980 -0.1599 
-0.0879 -1.1857 -0.4581 
-0.2302 -0.5384 -2.1302 
Eig. Value: -1.0009 -0.9691 -2.3791 
O: -1.9472 0.3903 -0.3771 
0.3930 -1.1841 0.2021 
-0.3941 0.2296 -1.1911 
Eig. Value: -2.2885 -1.0624 -0.9715 
O: -1.0494 -0.1996 0.0449 
-0.2099 -2.0139 0.1931 
0.0207 0.1332 -0.9920 
Eig. Value: -1.0078 -2.0810 -0.9666 
O: -1.9164 -0.1488 0.5814 
-0.0973 -1.0011 0.0568 
0.6101 0.0533 -1.3421 
Eig. Value: -2.3042 -0.9988 -0.9566 
Na: 1.0459 0.0415 -0.1125 
0.0243 1.1445 -0.0659 
-0.0429 0.0239 1.0947 
Eig. Value: 0.9875 1.1124 1.1851 
S: 3.3374 -0.0242 0.0375 
-0.0584 3.5352 0.1068 
-0.1026 0.0154 3.4255 
Eig. Value: 3.3243 3.5736 3.4003 
O: -1.1420 -0.1107 0.4156 
-0.1208 -1.0769 0.2504 
0.4798 0.3356 -2.1302 
Eig. Value: -0.9691 -1.0009 -2.3791 
O: -1.3732 0.5132 -0.2751 
0.5105 -1.7581 0.3277 
-0.3054 0.3387 -1.1911 
Eig. Value: -1.0624 -2.2885 -0.9715 
O: -1.8913 -0.3861 -0.1798 
-0.3758 -1.1720 -0.0836 
-0.1261 -0.0476 -0.9920 
Eig. Value: -2.0810 -1.0078 -0.9666 
O: -0.9902 0.0966 0.0635 
0.0450 -1.9273 -0.5807 
0.0728 -0.6081 -1.3421 
Eig. Value: -0.9988 -2.3042 -0.9566 
Mg: 2.2890 -0.1002 0.0170 
-0.1002 2.2471 -0.0138 
0.0863 -0.0701 2.2706 
Eig. Value: 2.4037 2.1657 2.2373 
Na: 1.1271 0.0413 0.0414 
0.0586 1.0632 0.1236 
-0.0322 0.0371 1.0947 
Eig. Value: 1.1124 0.9875 1.1851 
S: 3.5435 -0.0153 -0.0969 
0.0189 3.3292 -0.0586 
-0.0361 0.0973 3.4255 
Eig. Value: 3.5736 3.3242 3.4003 
O: -1.0332 -0.0980 -0.1599 
-0.0879 -1.1857 -0.4581 
-0.2302 -0.5384 -2.1302 
Eig. Value: -1.0009 -0.9691 -2.3791 
O: -1.9472 0.3903 -0.3771 
0.3930 -1.1841 0.2021 
-0.3941 0.2296 -1.1911 
Eig. Value: -2.2885 -1.0624 -0.9715 
O: -1.0494 -0.1996 0.0449 
-0.2099 -2.0139 0.1931 
0.0207 0.1332 -0.9920 
Eig. Value: -1.0078 -2.0810 -0.9666 
O: -1.9164 -0.1488 0.5814 
-0.0973 -1.0011 0.0568 
0.6101 0.0533 -1.3421 
Eig. Value: -2.3042 -0.9988 -0.9566 
Na: 1.0459 0.0415 -0.1125 
0.0243 1.1445 -0.0659 
-0.0429 0.0239 1.0947 
Eig. Value: 0.9875 1.1124 1.1851 
S: 3.3374 -0.0242 0.0375 
-0.0584 3.5352 0.1068 
-0.1026 0.0154 3.4255 
Eig. Value: 3.3243 3.5736 3.4003 
O: -1.1420 -0.1107 0.4156 
-0.1208 -1.0769 0.2504 
0.4798 0.3356 -2.1302 
Eig. Value: -0.9691 -1.0009 -2.3791 
O: -1.3732 0.5132 -0.2751 
0.5105 -1.7581 0.3277 
-0.3054 0.3387 -1.1911 
Eig. Value: -1.0624 -2.2885 -0.9715 
O: -1.8913 -0.3861 -0.1798 
-0.3758 -1.1720 -0.0836 
-0.1261 -0.0476 -0.9920 
Eig. Value: -2.0810 -1.0078 -0.9666 
O: -0.9902 0.0966 0.0635 
0.0450 -1.9273 -0.5807 
0.0728 -0.6081 -1.3421 
Eig. Value: -0.9988 -2.3042 -0.9566 
Atom type 

Dielectric tensors: 

 
Ɛ2.4082 0.0000 0.0000 
0.0000 2.4103 0.0000 
0.0000 0.0000 2.4025 
Eig. Value: 2.4079 2.4175 2.3956 
Refractive index (N): 1.5518 0.0000 0.0000 
0.0000 1.5525 0.0000 
0.0000 0.0000 1.5500 
Eig. Value: 1.5517 1.5548 1.5478 
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 
 

Available spectra for Na2Mg(SO4)2



2 spectra available in the database:

ID: CalcCond: Comment:
w000420  TheoStr   
w000421  ExpVol