-    EUCRYPTITE     -    LiAlSiO4

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:  146  R3 
Lattice parameters (Å):  13.5320  13.5320  9.0440 
Angles (°):  90  90  120 

Symmetry (theoretical): 

Space group:  146  R3 
Lattice parameters (Å):  8.1867  8.1867  8.1867 
Angles (°):  107.84  107.84  107.84 

Cell contents: 

Number of atoms:  42 
Number of atom types: 
Chemical composition: 

Atomic positions (theoretical):

Li:  0.2317  0.4559  0.0613 
Li:  0.7727  0.5423  0.9407 
Si:  0.2802  0.0994  0.8698 
Al:  0.7208  0.9004  0.1331 
Si:  0.7938  0.3857  0.5701 
Al:  0.2077  0.6145  0.4317 
O:  0.3525  0.6511  0.3187 
O:  0.6667  0.3522  0.6844 
O:  0.6718  0.9448  0.6095 
O:  0.3131  0.0416  0.3765 
O:  0.9640  0.2821  0.9532 
O:  0.0381  0.7279  0.0625 
O:  0.5848  0.9084  0.2580 
O:  0.4063  0.0891  0.7529 
Li:  0.4559  0.0613  0.2317 
Li:  0.5423  0.9407  0.7727 
Si:  0.0994  0.8698  0.2802 
Al:  0.9004  0.1331  0.7208 
Si:  0.3857  0.5701  0.7938 
Al:  0.6145  0.4317  0.2077 
O:  0.6511  0.3187  0.3525 
O:  0.3522  0.6844  0.6667 
O:  0.9448  0.6095  0.6718 
O:  0.0416  0.3765  0.3131 
O:  0.2821  0.9532  0.9640 
O:  0.7279  0.0625  0.0381 
O:  0.9084  0.2580  0.5848 
O:  0.0891  0.7529  0.4063 
Li:  0.0613  0.2317  0.4559 
Li:  0.9407  0.7727  0.5423 
Si:  0.8698  0.2802  0.0994 
Al:  0.1331  0.7208  0.9004 
Si:  0.5701  0.7938  0.3857 
Al:  0.4317  0.2077  0.6145 
O:  0.3187  0.3525  0.6511 
O:  0.6844  0.6667  0.3522 
O:  0.6095  0.6718  0.9448 
O:  0.3765  0.3131  0.0416 
O:  0.9532  0.9640  0.2821 
O:  0.0625  0.0381  0.7279 
O:  0.2580  0.5848  0.9084 
O:  0.7529  0.4063  0.0891 
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.