  X-ray absorption spectra of oxide systems Ba_{1-x}K_xBiO_3 and BaPbO_3 above
Bi- and Pb-L3 absorption edges were investigated. It was shown that oxygen ions
move in double-well potential and their oscillations are correlated with charge
carrier movement. Observed breathing-like oxygen vibration in double-well
potential with large amplitude and low frequency causes the strong
electron-phonon coupling and high Tc values in doped BaBiO_3. Based on the
experimental data, the model of relationship of electronic and local crystal
structures is proposed that is in a good agreement with the results of
transport measurements, inelastic neutron and electron scattering, Raman
scattering, and photoemission spectroscopy. In the framework of the model the
possible reasons of superconductivity in perovskite-like oxides are discussed.
