Definition Wavenumber, as used in spectroscopy and most chemistry fields, is defined as the number of wavelengths per unit distance, typically centimeters (cm−1): where λ is the wavelength. It is sometimes called the "spectroscopic wavenumber". It equals the spatial frequency.
definition wavenumber as used in spectroscopy and most chemistry fields is defined as the number of wavelengths per unit distance typically centimeters (cm−1) where λ is the wavelength it is sometimes called the "spectroscopic wavenumber" it equals the spatial frequency