E6 X-ray emission spectrometry

Excitation of the inner electrons of atoms promotes some to higher energies. In falling back to lower levels, they emit radiation in the X-ray region, characteristic of the element concerned. 

Excitation by high-energy electrons, radioactive particles or X-rays may be used. Analysis of the emitted X-rays using crystal analyzers is followed by detection using gas ionization detectors or scintillation counters. Nondispersive semiconductor detectors and multichannel pulse height analyzers are often used in conjunction with scanning electron microscopes. 

Elemental analysis of metal and mineral samples as well as surface studies and the determination of heavy metals in jjetroleum are typical uses. 

Moseley s law states that the reciprocal of the wavelength of each characteristic series of X-rays (for example, the Kctj series) is related to the atomic number Z of the element by the formula  

In a dispersive instrument, the specimen is the target for bombardment by high energy X-rays from the source, generally an X-ray tube containing a target such as tungsten, onto which electrons are accelerated by a 50 kV potential difference. These primary X-rays excite the specimen to produce X-rays 

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