The Kaiser (K) is a unit of energy. A common form is kiloKaiser (kK), for which 1 kK = 1000 cm<sup>âÂÂ1</sup>, where cm<sup>âÂÂ1</sup> is the unit of wavenumber or inverse wavelength. This unit is most commonly used with respect to energy transitions between electronic states in inorganic complexes.
Kilokaiser is a common but incorrect spelling of the unit kiloKayser. The unit is named after Heinrich Gustav Johannes Kayser (16 March 1853 â 14 October 1940), a German physicist.