Flow of energy through space propagated as synchronized sinusoidal waves of the electric field,
\(\boldsymbol{E}\), and the magnetic field
\(\boldsymbol{H}\).
Notes: - Electromagnetic radiation is characterized by frequency \(\nu\), wavelength \(\lambda\), and speed \(c\), where \(\nu\lambda = c\).
- The wavelength and velocity change when radiation enters a medium. In its interaction with atoms and molecules, radiation behaves like particles, called photons, with zero mass, energy \(h\nu\), and momentum \(h/\lambda\), where \(h\) is the Planck constant \(h = \pu{6.62607015E-34 J s}\).
Source:
PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 657 (https://doi.org/10.1515/pac-2019-0203)