The crystal structure is a specific arrangement of atoms, while when a crystal has many simplest repeating unit this called a unit cell .As we know in cubic ,there are three type of unit cells.
A simple cubic unit cell (SC) that contains eight identical particles on the eight corner,the body centered cubic unit cell (BCC) that contains nine identical particles(one on the centre and eight on the corner) and the face centered cubic unit cell (FCC) that contains 14 identical particles (6 faces and 8 on the corner).
A simple cubic unit cell (SC) that contains eight identical particles on the eight corner,the body centered cubic unit cell (BCC) that contains nine identical particles(one on the centre and eight on the corner) and the face centered cubic unit cell (FCC) that contains 14 identical particles (6 faces and 8 on the corner).
I found it interesting how we can construct different primitive cells that are equally valid in describing a crystal.
ReplyDeleteIf we can find any three vectors a1, a2 and a3 from one point of a lattice that can be fitted into R = n1a1+n2a2+n3a3 we have a Bravais lattice. There is not a unique way to choose a1, a2 and a3.
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