Structure of Crystalline Solids - Chapter 4 Flashcards Preview

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Flashcards in Structure of Crystalline Solids - Chapter 4 Deck (18)
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1
Q

Coordination number of BCC?

A

8

2
Q

Unit number of atoms in BCC?

A

2

3
Q

Unit number of atoms formula?

A

N = Ni + Nf/2 + Nc/8

4
Q

Atomic packing factor of BCC?

A

0.68

5
Q

FCC:

A

Face Centered Cubic Structure

Atoms located at each of the corners and the centers of all the cube faces.

6
Q

Three Main Crystal structures:

A

FCC - Face-centered structure
BCC - Body-centered structure
HCP -

7
Q

FCC cube length a?

A

a = 2R* Sqrt[2]

8
Q

FCC coordination number?

A

12

9
Q

Unit number of atoms in FCC?

A

4

10
Q

Atomic Packing Factor of FCC?

A

0.74

11
Q

Atomic Packing Factor(APF)?

A

The APF is the sum of the sphere volumes of all atoms within a unit cell divided by the unit cell volume.

APF = Volume of atoms in a unit cell/total unite cell volume

12
Q

BCC:

A

Body centered cubic structure:

Atoms located at all eight corners and a single atom at the cubic center.

13
Q

BCC unit cell length a?

A

a = 4R/Sqrt[3]

14
Q

HCP:

A

Hexagonal close-packed:

The top and bottom faces of the unit cell consists of six atoms that form regular hexagons and surround a single atom in the center. Another plane that provides three additional atoms to the unit cell is situated between the top and bottom planes.

15
Q

Number of atoms per unit cell for HCP:

A

N = Ni + Nf/2 + Nc/6

16
Q

Unit number of atoms in HCP:

A

N = 3 + 2/2 + 12/6 = 6

17
Q

Coordination number of HCP?

A

12

18
Q

Atomic packing factor of HCP?

A

0.74