Abstract Influence of the oxidation state of the mother 54 Mn radioisotope on the KL 2,3 L 2,3 Auger spectrum of the daughter 54 Cr isotope was investigated by annealing a 54 Mn source prepared by vacuum evaporation on a Pt backing. The spectrum was analyzed at the instrumental resolution of 4.5 eV using a combined electrostatic spectrometer. A chemical shift of −5 eV per oxidation degree was determined. The results obtained are discussed. The full KLL Auger spectrum of 54 Cr from the EC-decay of 54 Mn was also measured. Energies and relative intensities of the individual spectrum lines were determined and compared to available theoretical and experimental results. The absolute energy of 4791.8(14) eV measured for the dominant KL 2 L 3 ( 1 D 2 ) spectrum line was found to be higher by 14 eV than that of the semi-empirical calculations by Larkins. A contribution of the “atomic structure effect” to the discrepancy found is discussed.