CRYSTALLOGRAPHY -MUTHUMEENA V

1. SUBMITTED
V.MUTHUMEENA
2nd BIO TECHNOLOGY

2.  The word “crystallography” is derived from
the greek words crystallon “cold drop,frozen
drop”,with its meaning extending to all
solids.
APPLICATIONS OF CRY
STALLOGRAPHY:
 It is determine the molecular structure of a
crystal.
 x-ray crystallography is a powerful technique.
 2D diffraction pattern comes to mind for most.

3.  It was the principles of x-ray diffraction
to analyze the sample ,but it is done in
many different directions so that the 3D
structure can be built up.

4.  Miller indices from a notation system in
crystallography for planes in crystal
lattices.
 Lattice planes h,k,l.

5.  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.

6.  nλ=2d sinθ
 λ=wavelength of the electrons.
 d=spacing of the crystal planes.
 n=integer.
RECIPROCAL LATTICE:
 It represents the fourier transform of another
lattice(bravais lattice).
 In normal usage,the initial lattice is usually a
periodic spatial function in real –space and is also
known as the direct lattice.

7.  Thin films and single crystal meterials.
 Customizable high resolution x-ray
diffractometers for characterizing.
 Multi layer coatings.
 Reciprocal space mapping.
ROTATING CRYSTAL METHOD:
 Any method of studying crystalline struc tures
by x-ray or neutron diffraction in which a
monochromatic, collimated beam of x-rays or
neutrons falls on a single crystal that is
rotated about an axis perpenticular to the
beam.

8.  It is a scientific tecnique using x-ray,
neutron or electron diffraction on powder
or microcrystalline samples for structural
characterization of materials. An
instrument dedicated to performing such
powder measurements is called powder
method.