Ionizing Radiation

X-rays, along with gamma and cosmic rays are known as ionizing radiation and are found at the high energy, high frequency, short wavelength end of the spectrum. Ionizing radiation when absorbed by atoms or molecules knocks electrons out of the inner shells of the atoms or molecules, thereby converting the atoms or molecules to positively-charged ions - hence, the name ionizing radiation.

X-rays are used in chemistry to study the inner shell electronic structure of atoms and molecules and also to determine the exact positions of atoms in molecules in the crystal state, which allows the exact structure of the molecule to be determined. In medicine, x-rays are used to view bones and other hard tissues.

A simplified diagram of x-ray crystallography.

X-rays and gamma rays result from nuclear reactions, nuclear decay, and nuclear explosions. Aside from damage done by the heat and shockwave of the blast in a nuclear explosion, ionizing radiation from the explosion causes ionization of atoms. In living systems, the resulting ions and their reaction products known as free radicals, which are chemical species having unpaired electrons, are extremely reactive and thus extremely toxic and cause what is known as radiation poisoning. At lower doses, ionizing radiation causes genetic damage.

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