Introduction to crystal structure
Dr. Kuldeep Kumar
Assistant Professor in Physics
SGTB Khalsa College, University of Delhi
Solid State Physics?
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Motion of electron in a lattice.
Interaction of electron with lattice vibration
(phonon).
Interaction of electron in lattice under electric
and magnetic field.
Electron electron coupling in lattice.
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Prerequisite to Crystal structure
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Vector Analysis (dot and cross product, div of a
vector etc. ).
Fourier series and Fourier transformation.
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Materials
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Solid
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Liquid
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Gas
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Plasma
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Solids
Hangzhou Freqcontrol
Electronic Technology Ltd
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Crystalline (Single Crystal)
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Non-crystalline (Amorphous)
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Polycrystalline
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Nano-crystalline
Journal of Nanomaterials,
2015, 1687-4110, ID 598734
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A Review. Polymers
2020, 12, 1304
K Kumar, P Arun, CR Kant, NC
Mehra, V MathewApplied Physics A
99 (1), 305-310
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Crystalline materials and their
structure.
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Crystal structure= Lattice +Basis
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It can be constructed by the infinite repetition of these identical structural units in space.
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Structure can be described in terms of a lattice, with a group of atoms attached to each lattice point. The group of atoms is the basis.
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Lattice -a point in space.
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An infinite array of discrete points with an arrangement and orientation that appears exactly the same, from any of the points the array is viewed from.
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Basis- atom/molecule/unitcell.
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Unit cell-the smallest group of atoms which has the overall symmetry of a crystal, and from which the entire lattice can be built up by repetition in three dimensions.
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Primitive cell
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A primitive cell is a unit cell that contains exactly one lattice point. It is
the smallest possible cell. If there is a lattice point at the edge of a cell
and thus shared with another cell, it is only counted half.
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2d and 3d lattice
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https://en.wikipedia.org/wiki/Bravais_lattice
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https://en.wikipedia.org/wiki/Bravais_lattice
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Honeycomb
Recommended book for the course
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