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4.1 Neutron Diffraction Technique

Diffraction of neutron by crystal lattices is similar with
X-rays or gamma radiations. Neutrons beam will be
diffracted when its passing some grating like the ar-
rangement of lattice planes. This causes the positive
and negative interference will occur and the interac-
tion with each other results in diffraction pattern af-
ter the grating. Supposing the grating is the arrange-
ment of lattice planes of the atom, thus, neutron will
be diffracted after the interaction with the nucleus in
the atom on the lattice planes.

4.2 Design of devices

In general, design of neutron diffraction instrument is
varies, depending on the neutron source, whether it
is from nuclear reactor or spallation machine. Another
important consideration in design of neutron diffraction
instrument is the utilization of neutron energy, since
neutron exist in various energy as given in neutron
spectrum pattern. The spectrum itself is the charac-
teristic of neutron source. Even though the energy
spectrum is large covers from several eV upto 20 MeV,
but only energy within cold to thermal neutrons are
widely utilized in the diffraction instrument. Neverthe-
less, only monochromatic neutron is used each time
neutron diffraction device do the measurement. There-

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