Assignments

 

Press-Fit Kit For Crystal Structures

 

The idea is to build a press-fit kit that can make any crystalline strucutre of materials. The crystal structure of a material is described by a unit cell and the kit can be used to build these lattice unit cells.

 

Building Block

 

 

 

Different combination of above building blocks can be used to build the unit cells of all the crystal structures. Here, I have shown few examples -

 

1) Hexagonal-

 

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Then individual ball along with sticks are used to create the hexagonal unit cell as shown below

 

 

 

2) Simple Cubic -

 

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simple cubic lattice is built with above balls are shown below

 

 

 

3) Face Centered Cubic

 

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stucture created is shown below

 

 

 

4) Diamond Structure

 

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The structure created is shown below

 

 

please not that the diffierence is because there are some hanging atmos in the demo structure (the light blue lines are not the bond between atoms). To see similarities try to compair the bottom three atoms of both the images.

 

 

 

Discussion on building the kit -

 

I wanted each ball (atoms) to be as small as possible, So I started with balls of diamter 12mm and chanded the diameter in steps of 1mm till 20mm(~cardboard thickness). Figure below shows the cut-out result of my first attempt.

 

 

and here are some attemps with the cutouts of circles with different diameters.

 

 

The best fit was observed when diameter was 16mm(figure below)

 

 

However, there was no rigid to hold the sticks in some slot so I decided to increase the diamter of the balls.