Cell Geometry

Question 1

Body-centered cubic (BCC)

Answer 1

8 corner atoms, 1 body center
atom bonds touch along diagonal
all atoms the same
CN:8

Question 2

Face-centered cubic (FCC)

Answer 2

8 corner atoms, 6 face centers
face center: 1 atom at the center of each face
Atoms bond/touch along the diagonal of the face
all atoms the same
CN:12

Question 3

Hexagonal Closed Packed structure (HCP)

Answer 3

3 layers of atoms:
top and bottom: 6 atoms in a hexagon with one atom at the center
Middle: 3 atoms in triangular grooves

Question 4

How is the third miller index for a HCP

Answer 4

i=-(h+k)