³⁸Wavenumber, being the reciprocal of wavelengths in centimeters, may be thought of in terms of frequency: the greater the wavenumber, the higher the frequency of the light wave (the smaller its wavelength). In order to convert wavenumber into wavelength (in microns), reciprocate the wavenumber value and multiply by 10⁴. For example, a wavenumber of 2000 cm⁻¹ is equivalent to a wavelength of 5 microns. In order to convert wavenumber into wavelength (in nanometers), reciprocate the wavenumber value and multiply by 10⁷. For example, a wavenumber of 4000 cm⁻¹ is equivalent to a wavelength of 2500 nm.