Solid State Physics

FISIKA ZAT PADAT

PERTEMUAN KE-2

Anif Jamaluddin1

1Prodi P.Fisika, PMIPA, FKIP, Universitas Sebelas Maret, Surakarta

Solid State Physics

• Review• Index Miller• Jarak Bidang Kristal• Kerapatan Kristal• Cacat Kristal• Next Chapter

Outline

Solid State Physics

(c) 2003 Brooks/Cole Publishing / Thomson Learning™

Review

• Struktur Kristal• System Kristal• Simetri Kristal• Struktur Kristal pada tabel periodik

Solid State Physics

Index Miller

Solid State Physics

Index MillerDirection

• [hkl] represents a direction • <hkl> represents a family of directions • (hkl) represents a plane • {hkl} represents a family of planes

Solid State Physics

5a + 3b

a

b

Miller indices → [53]

(0,0)

(4,3)

Solid State Physics

3D Arah

[010]

[100]

[001]

[110]

[101]

[011]

[110]

Solid State Physics

Find intercepts along axes → 1 Take reciprocal → 1/1 1/ 1/ Convert to smallest integers in the same ratio → 1 0 0 Enclose in parenthesis → (1 0 0)

Bidang Kristal

Solid State Physics

Bidang Kristal

Solid State Physics

Bidang Kristal

Intercepts → 1 Plane → (100)Family → {100} → 3

Intercepts → 1 1 Plane → (110)Family → {110} → 6

Intercepts → 1 1 1Plane → (111)Family → {111} → 8(Octahedral plane)

Solid State Physics

Kerapatan SC

close-packed directions

a

R=0.5a

contains 8 x 1/8 = 1 atom/unit cell

Solid State Physics

KerapatanAtomic Packing Factor (APF)

APF = Volume of atoms in unit cell*

Volume of unit cell*assume hard spheres

APF =

a 3

unit cell

volume

4

3p (0.5a) 31

atoms

unit cellatom

volume

close-packed directions

a

R=0.5a

contains 8 x 1/8 = 1 atom/unit cell

• APF for a simple cubic structure = 0.52

Solid State Physics

• Coordination # = 8

ex: Cr, W, Fe (), Tantalum, Molybdenum

Kerapatan BCC

Solid State Physics

Kerapatan

a

APF =

4

3p ( 3 a/4 ) 32

atoms

unit cell atom

volume

a 3

unit cell

volume

length = 4R =

Close-packed directions:

3 a

• APF for a body-centered cubic structure = 0.68

aR

a 2

a 3

Solid State Physics

• Coordination # = 12

ex: Al, Cu, Au, Pb, Ni, Pt, Ag

4 atoms/unit cell: 6 face x 1/2 + 8 corners x 1/8

Solid State Physics

Solid State Physics

a

2 a

• APF for a face-centered cubic structure = 0.74Atomic Packing Factor: FCC

maximum achievable APF

APF =

4

3p ( 2 a/4 ) 34

atoms

unit cell atom

volume

a 3

unit cell

volume

Close-packed directions:

length = 4R = 2 a

Unit cell contains: 6 x 1/2 + 8 x 1/8

= 4 atoms/unit cell

Solid State Physics

•Latihan penentuan APF•Cacat Kristal

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