Crystallography
Kumkum Sanyal
Applied Physics Section
Thadomal Shahani Engineering College.
Bandra West, Mumbai - 400050
February 28, 2021
, Unit 02 : Crystallography
Prerequisites :
(Crystal Physics → Crystallographic parameters,Unit cell,
Space lattice;
Crystal structure → Simple cubic, Body-centered cubic,
Face-centered cubic, Diamond structure;
X-rays → Production, Properties)
Contents :
• Miller indices
• Interplanar Spacing
• X-ray diffraction and Bragg’s law
• Determination of Crystal structure using Bragg’s
diffractometer
2/27
, Basic Terms and Definitions of Crystallography
• Crystal: A crystal is a solid in which constituent atoms,
ions or molecules are arranged in a regular, periodic
repetitive manner in three-dimensional space extending
up to infinity.
• Space lattice: A three-dimensional array of dimensionless
points in space, each of which has an exactly identical
surrounding of neighboring points.
• Crystallographic parameters: The translational vectors or
the basis vectors ~a, ~b, ~c together with the inter-axial angles
between them α, β, γ are known as lattice parameters.
• Unit Cell: The smallest repeat unit of a crystal structure in
three-dimension, which shows the structural properties of
the bulk crystal.
3/27
Kumkum Sanyal
Applied Physics Section
Thadomal Shahani Engineering College.
Bandra West, Mumbai - 400050
February 28, 2021
, Unit 02 : Crystallography
Prerequisites :
(Crystal Physics → Crystallographic parameters,Unit cell,
Space lattice;
Crystal structure → Simple cubic, Body-centered cubic,
Face-centered cubic, Diamond structure;
X-rays → Production, Properties)
Contents :
• Miller indices
• Interplanar Spacing
• X-ray diffraction and Bragg’s law
• Determination of Crystal structure using Bragg’s
diffractometer
2/27
, Basic Terms and Definitions of Crystallography
• Crystal: A crystal is a solid in which constituent atoms,
ions or molecules are arranged in a regular, periodic
repetitive manner in three-dimensional space extending
up to infinity.
• Space lattice: A three-dimensional array of dimensionless
points in space, each of which has an exactly identical
surrounding of neighboring points.
• Crystallographic parameters: The translational vectors or
the basis vectors ~a, ~b, ~c together with the inter-axial angles
between them α, β, γ are known as lattice parameters.
• Unit Cell: The smallest repeat unit of a crystal structure in
three-dimension, which shows the structural properties of
the bulk crystal.
3/27
