Atomic Displacement Due To Irradiation:

The effects of radiation on plant materials depend on both the categories of radiation and the categories of material. This lesson discusses atomic displacements resulting from the several categories of radiation.

STATE how the subsequent types of radiation interact along with metals.

a. Gamma            d. Fast neutron

b.  Alpha              e. Slow neutron

c.  Beta               

DEFINE the subsequent terms:

a. Knock-on

b. Vacancy

c. Interstitial

Overview

Excitation of electrons and Ionization in metals is generates through beta and gamma radiation. An ionization and excitation dissipates much of the energy of heavier charged particles and does extremely little damage.   This is since electrons are associatively free to move and are just replaced. The net effect of beta and gamma radiation on metal is to produce a small amount of heat.

Heavier particles, such as protons, α-particles, fast neutrons, and fission fragments, will commonly transfer enough energy through elastic or inelastic collisions to erased nuclei from their lattice (crystalline) positions.  That addition of vacancies and interstitial atoms causes property changes within metals.   This effect of nuclear radiation is many times referred to as radiation dam age.

Within  materials  other  than  metals  in  that  chemical  bonds  are  significant  to  the  nature  of  the material, a electronic interactions (ionizations) are important since they could break chemical bonds.  That is important in materials such as organics.  A breaking of chemical bonds could lead to both smaller and larger molecules depending on to the repair mechanism.

In other case there are material property changes, and those changes tend to be greater for a provided dose than for metals, since much more of the radiation energy goes into ionization energy than into nuclear collisions.