This slide set corresponds to the MaterialsConcepts YouTube video "Muddiest Point- Unit Cell Calculations". Here's the link: http://www.youtube.com/watch?v=lIVVUHo471Q To study the vocab used in this video, visit this site: http://quizlet.com/21414803/21-crystal-structure-i-unit-cells-flash-cards/ This work was supported by NSF Grants #0836041 and #1226325.

1. Muddiest Points – Unit Cell
Muddiest Point 1: “Figuring how to find the properties of
atoms (FD,BD,APF etc) Just a lot if info at once.”
Muddiest Point 2: “I am very confused on the last activity. I
have no idea what just happened.”
Muddiest Point 3: “The calculations related to unit cells, APF,F
a/e/ length etc.”

2. Features of FCC
#corner
atoms?
#face
atoms?
Real
Gold
#
body
atoms?
# atoms faces, corners = # atoms / # =____ ____
UC =
Atoms
touch
At / UC__________
along
direc7on?
Atoms touch along direction? ______________
# atomic radii along touch
# R = ______
direction within UC?
Cube edge (lattice constant) ao = f (R) a = _________
Atomic
Packing
Factor
(APF)
Length FD = f (R) FD = _______
APF
=
(vol
atoms/UC)
/
(vol
UC)
Length BD = f (R) BD = _______
Cube volume V = f(R) V / UC = ________
Atomic Packing Factor =
APF =______
Vol atoms / Vol UC
Coordination Number =
CN =_______
# of atoms touching one atom 2

3. Finding
a
(Unit
Cell
Edge)
in
terms
of
R

4. Finding
the
Body
Diagonal
in
terms
of
R