The electronic structure of (Ba1-xKx)BiO3 has been calculated by using a supercell LDA-LMTO-ASA method at some compositions. The calculation was performed by doubling unit-cell for x=0.25, 0.5 and 1.0 and by quadruple unit-cell for x = 0.25 and 0.75. The band parameters, total density of states TDOS (EF), partial DOS PDOS (EF) and self-consistent potential Vt(r), obtained from LMTO calculation were combined with the experimental Debye temperature ΘD From this, the Hopfield constant ηt, electron-phonon coupling constant λ and superconducting transition temperature Tc and its x-dependence were evaluated by the McMillan theory and Gaspari-Gyorffy approximation. It was found that the λ≈1 and the maximum Tc≈ 10K which is a slowly varying function of composition x. Our results exhibit a significant difference between the traditional theory and experiment and imply a mechanism which would be related to the composition dependent structure transformation besides the BCS methanism.
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