Question

what is the meaning of wavenumber

Answer 1

Wavenumber is defined as the number of wavelengths per unit distance.

Answer 2

Wavenumber, as used in spectroscopy and most chemistry fields, is defined as the number of wavelengths per unit distance, typically centimeters: ν ~ = 1 λ {\displaystyle {\tilde {\nu }}\;=\;{\frac {1}{\lambda }}}

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