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<title>GAMGI Tutorials: CsCl crystalline structure</title>
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<h1>CsCl crystalline structure</h1>
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<li><span>Page 1</span></li>
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The CsCl structure is observed in metallic compounds such as CuZn
(beta-brass), AlNi, AgMg and CuPd, but also in ionic crystals
with equal number of cations and anions, when the cation is
slightly smaller than the anion: CsCl, Nh4Cl, TlBr, etc.
<p/>
To build this structure, first we create the cell with the
observed lattice parameters, then the Cs, Cl atoms used as models,
with the observed ionic radius, and then link the cell with the
atoms.
<ol>
<li>
Press <b>Cell->Create</b> and set <b>System</b> to <b>c</b>,
<b>Lattice</b> to <b>P</b> (Primitive Cubic) and <b>a</b>
to <b>4.018</b> (so ions will be in contact along <111>
directions). Press <b>Ok</b> to create the cell.
</li>
<li>
Select <b>Atom->Create</b> and set <b>Style</b> to <b>Solid</b>,
<b>Size</b> to <b>1.0</b> and <b>Variancy</b> to <b>1.0</b>.
Set <b>Element</b> to <b>Cs</b>, <b>Radius</b> to <b>1.670</b>
(ionic radius for Cs+) and press the mouse over the graphic
area. A Cs atom is created where the mouse was pressed.
</li>
<li>
Set <b>Element</b> to <b>Cl</b>, <b>Radius</b> to <b>1.810</b>
(ionic radius for Cl-) and press the mouse over the graphic
area. A Cl atom is created where the mouse was pressed.
</li>
<li>
Press <b>Cell->Link</b> and select the <b>Crystal</b> link method.
Press the mouse over the cell, and then over the Cs atom,
to identify the objects to link. Set the <b>x</b>, <b>y</b>, <b>z</b>
coordinates (<b>Position</b> page) to <b>0.5</b>, <b>0.5</b>,
<b>0.5</b> and press <b>Ok</b>. 1 atom of Cs is now visible,
in the center, inside the cell.
</li>
<li>
Repeat the link procedure above, but this time pressing the mouse
over the Cl atom, and setting the <b>x</b>, <b>y</b>, <b>z</b>
coordinates to <b>0.0</b>, <b>0.0</b>, <b>0.0</b>. 8 atoms of Cl
are now visible, in the vertices, corresponding to a total
of 1 atom inside the cell.
</li>
<li>
Select <b>Light->Create</b> and press <b>Ok</b>, to add a light
and give atoms a three dimensional look.
</li>
<li>
Remove the Cs,Cl atoms used as models during the building process,
pressing <b>Atom->Remove</b> and clicking the mouse over the two atoms.
</li>
<li>Rotate,move,scale the CsCl cell with the mouse. Press
<b>Atom->Measure</b> to determine lengths and angles between atoms.
</li>
</ol>
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