Abstract: A new concept, a resonant orbital rearrangement ROR, has been introduced to explain an anomalously weak intensity of F Kα X-ray emitted from a K 1 L 1 doubly ionized state and an unassigned M peak in KVV Auger spectra of KF. ROR has been used for explaining resonance between HOMO at K 0 L 0 and LUMO at K 1 L 0 states during F 1s ionization or X-ray and Auger decay processes, where K m L n denotes m and n vacancies on K and L shells, respectively. Molecular orbitals describing the K m L n state were calculated by the DV-X α method. Ionization cross sections, F Kα X-ray energies and X-ray transition probabilities were calculated using the semi-classical approximations (SCA), the Slater's transition state method and the dipole approximation, respectively. In the present study we found excellent linearities between ROR probabilities and the M line intensities, and between fluorescence yields for a K 1 L 1 doubly ionized state and relative X-ray intensities of (K 1 L 1 /K 1 L 0 ). Here X-ray and Auger emission spectra were studied, which were emitted from the alkali-metal fluorides, i.e. NaF, KF, RbF and CsF. All the intensities of F Kα X-rays and KVV Auger electrons have successfully been explained for the first time.