# Aluminum Crystal Structure

L

#### LABQT

For my project, I am creating a pure aluminum model with styro foam balls and toothpicks. I know this structure is a "face-centered cubic". However, I don't know the bonding angles and what kind of bonding shape (tetrahedral, octahedral ...), I need the information for the write-up. Can someone help please.

#### FZ+

Er... being a metal, I wouldn't think pure aluminium would really form any distinct bonds that you can represent. Most models of metal crystals are simply layers of balls glued onto each other.

To visualise a face centred cubic structure, picture a cube with eight aluminium particles, one on each vertex. At the centre of each face, there is an additional particle. Repeat pattern many times, et viola.

eg.

Code:
Layer 1:

O   O   O
O   O
O   O   O
O   O
O   O   O

Layer  2:

O   O
O   O   O
O   O
O   O   O
O   O

Layer 3:

O   O   O
O   O
O   O   O
O   O
O   O   O
Don't trust my crappy diagram so much though.

Last edited:
L

#### LABQT

Thanks for the reply. Now I understand.

I think the third layer is wrong.

#### 03myersd

I think the third layer is wrong.
The third layer is identical to the first layer. And the fourth would be identical to the second and so on. It is basically the way in which the atoms stack together the best. If all the layers were identical there would be too much empty space between atoms.

But In aluminium, there is FCC lattice. That means, the third layer must be different also. It has ABCABC-----pattern and not ABAB_____ pattern

#### Mapes

Homework Helper
Gold Member
But In aluminium, there is FCC lattice. That means, the third layer must be different also. It has ABCABC-----pattern and not ABAB_____ pattern
This is correct if one is drawing the close-packed {111} planes. But FZ+ drew the {100} planes correctly; every other {100} plane is identical.

"Aluminum Crystal Structure"

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