1_introtocrystal
DESCRIPTION
crystalografiTRANSCRIPT
![Page 1: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/1.jpg)
1. Introduction to Crystal 1. What is a crystal? 2. Lattice 3. Unit Cell 4. The 14 Bravais Lattices
Prof. Bondan T. Sofyan
![Page 2: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/2.jpg)
Steel (metal)
Bridge high resolution transmission electron microscope (HRTEM)
1. What is a crystal?
Ferrite pearlite Prof. Bondan T. Sofyan
![Page 3: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/3.jpg)
BCC (body centred cubic)
1. What is a crystal?
HRTEM
Periodic arrangement of atoms CRYSTAL
{111}α plates
small particle
(111)α
(111
)α
(002)α
0.23 nm
![Page 4: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/4.jpg)
vertical fin (aluminium)
optical microscope
50 nm
θ'
Ω
(111
)
(111)
(002)
Ω
Ω
small particle
transmission electron microscope (TEM)
1. What is a crystal?
Prof. Bondan T. Sofyan
![Page 5: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/5.jpg)
{111}α plates
small particle
(111)α
(111
)α
(002)α
0.23 nm
(HRTEM) (111
)
(111)
(002)
Aluminium
0.23 nm
1. What is a crystal?
Prof. Bondan T. Sofyan
![Page 6: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/6.jpg)
Periodic arrangement of atoms
FCC (face centred cubic)
1. What is a crystal?
CRYSTAL
Prof. Bondan T. Sofyan
![Page 7: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/7.jpg)
So, what is a crystal ?
• A crystal is a solid consisting of a three-dimensional periodic ordering of atoms, ions or molecules.
• Kristal adalah padatan yang atom-atomnya, ion-ionnya atau molekul-molekulnya berada dalam susunan 3 dimensi yang teratur.
• This kind of solid is then termed as: crystalline solid (padatan kristalin), while at the other end, the solid, which does not have a periodical ordering of atoms, is called amorphous solid (padatan amorf).
• Most metals (Al, steel, Cu and their alloy (paduan)) are crystalline. While glass and most polymers (plastics, rubber, etc) are amorphous.
Prof. Bondan T. Sofyan
![Page 8: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/8.jpg)
There are two kinds of crystalline solid: – Single crystal (kristal tunggal), where ALL atoms in
that material arrange themselves in one direction only.
– Polycrystal (polikristal). This material consists of several group of atoms (grains) that have different orientation to each other.
1. What is a crystal?
Prof. Bondan T. Sofyan
![Page 9: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/9.jpg)
Single crystal
Polycrystal
GRAIN (BUTIR)
In one grain, atoms are oriented at the same direction
Prof. Bondan T. Sofyan
![Page 10: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/10.jpg)
2. Lattice (Kisi) • As explained before, a three-dimensional periodic
arrangement of atoms, ions or molecules is always present in all crystals. If each atom is represented by a point (its centre of gravity), the arrangement is called a lattice.
Three-dimensional periodic arrangement of atoms in a crystal
The lattice of the crystal Prof. Bondan T. Sofyan
![Page 11: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/11.jpg)
• A Lattice is a three dimensional arrangement of points in which all of the points have identical surroundings
• Kisi adalah susunan titik-titik dalam ruang tiga dimensi
sedemikian rupa sehingga setiap titik memiliki lingkungan yang sama.
2. Lattice (Kisi)
Prof. Bondan T. Sofyan
![Page 12: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/12.jpg)
• A Unit Cell is the fundamental or most primitive unit of the lattice.
• Sel satuan adalah satuan (unit) terkecil dari kisi.
• From the above illustration, the fundamental unit of the lattice is a (simple) cubic. Therefore, it is said that the unit cell of the lattice is simple cubic.
3. Unit Cell (Sel Satuan)
Prof. Bondan T. Sofyan
![Page 13: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/13.jpg)
• The unit cell is defined as having crystallographic axes (sumbu kristalografi), which may be described in terms of their length (panjang) a, b & c and the angles (sudut) α, β and γ. These lengths and angles are referred to as the Lattice Parameters or Lattice Constants of the unit cell.
• For lattice parameters, although we could use special
values of a, b and c and α, β and γ to generate a variety of lengths, shapes etc. only SEVEN types of cell are necessary to describe all crystals and called: The Seven Crystal System. Hanya ada TUJUH jenis sel satuan untuk seluruh jenis kristal yang ada di alam. Ini disebut: Tujuh Sistem Kristal.
3. Unit Cell (Sel Satuan)
Prof. Bondan T. Sofyan
![Page 14: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/14.jpg)
• The 7 crystal systems correspond to 7 point lattices (simply by putting points at the corners of the unit cell). However, there are other arrangements of points that satisfy the requirements of a point lattice. Bravais demonstrated that there are in fact 14 possible point lattices and no more.
• One (Seseorang) may therefore consider that the 14
Bravais lattices (or point lattices) fall into 7 fundamental classes.
• We distinguish the 14 Bravais lattices on the basis of
Simple (or Primitive), and Non-Primitive.
3. Unit Cell (Sel Satuan)
Prof. Bondan T. Sofyan
![Page 15: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/15.jpg)
• Simple or primitive lattices have one lattice point (or atom) per unit cell.
• Non-Primitive cells have > 1. • A lattice point at the interior (di dalam) of a cell belongs
to the cell. Lattice points in a cell face are shared (dibagi) by two cells. Lattice points on the corner are shared by 8 cells.
• The number of lattice points per unit cell will be given by:
N = Ni + Nf/2 + Nc/8
3. Unit Cell (Sel Satuan)
Prof. Bondan T. Sofyan
![Page 16: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/16.jpg)
Prof. Bondan T. Sofyan
![Page 17: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/17.jpg)
Cubic Three equal axes at rightangles.a=b=c. α=β=γ=90°
SimpleBody-centredFace-centred
PIF
Tetragonal Three equal axes at rightangles, two equal.a=b≠c. α=β=γ=90°
SimpleBody-centred
PI
Orthorhombic Three unequal axes at rightangles.a≠b≠c. α=β=γ=90°
SimpleBody-centredBase-centredFace-centred
PICF
Rhombohedral(trigonal)
3 equal axes, equally inclined.a=b=c. α=β=γ≠90°
Simple R
Hexagonal Two equal, coplanar axes at120°, 3rd axis at right angles.a=b≠c. α=β=90°, γ=120°
Simple P
Monoclinic Three unequal axes, one pairnot at right angles. a≠b≠c. α=γ=90°≠β
SimpleBase-centred
PC
Triclinic Three unequal axes, unequallyinclined, none at right angles.a≠b≠c. α≠β≠γ≠90°
Simple P
3. Unit Cell (Sel Satuan)
Prof. Bondan T. Sofyan
![Page 18: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/18.jpg)
a
Simple (P)
Body-centred (I)
Face-centred (F)
4. The 14 Bravais Lattices
Cubic
Prof. Bondan T. Sofyan
![Page 19: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/19.jpg)
Tetragonal
Simple (P) Body-centred (I)
a a
c
4. The 14 Bravais Lattices
Prof. Bondan T. Sofyan
![Page 20: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/20.jpg)
Orthorhombic
c
a b Simple (P) Body-centred (I)
Base-centred (C) Face-centred (F)
4. The 14 Bravais Lattices
![Page 21: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/21.jpg)
α a
Rhombohedral (R) Hexagonal (P)
120º
c
a
4. The 14 Bravais Lattices
Prof. Bondan T. Sofyan
![Page 22: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/22.jpg)
Monoclinic
β a b
c
Simple (P)
Base-centred (C)
4. The 14 Bravais Lattices
Prof. Bondan T. Sofyan
![Page 23: 1_IntrotoCrystal](https://reader033.vdocuments.us/reader033/viewer/2022051620/55cf9c0f550346d033a86d38/html5/thumbnails/23.jpg)
Triclinic
α β
γ a
b
c
4. The 14 Bravais Lattices
Simple (P) Prof. Bondan T. Sofyan