A linearised form for the screened form factors of electron-ion interaction is proposed and applied for the prediction of superconducting state parameters viz. electron-phonon coupling strength A, Coulomb pseudopotential y * , transition temperature T,, isotope effect exponent a, and the interaction strength N0V. Good agreement between the computed results, experimental data, and the results of Allen and Cohen based on the HA potential, supports the proposition.Es wird eine linearisierte Form fur die abgeschirmten Formfaktoren der Elektronen-IonenWechselwirkung vorgeschlagen. Sie wird fur die Vorhersage der Parameter des Supraleitungszustandes, z.B. der Elektronen-Phononen-Kopplungsstiirke 1, des Coulombpseudopotentials y * , der ubergangstemperatur T,, dem Exponenten a des Isotopeneffekts und der Wechselwirkungsstsrke N,V, benutzt. Die gute U'bereinstimmung zwischen den erhaltenen Ergebnissen, experimentellen Werten und den Ergebnissen von Allen und Cohen auf der Grundlage des HAPotentids, bestatigt den Vorschlag.

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The superconducting state parameters (SSP) viz. electron-phonon coupling strength (λ), Coulomb pseudopotential (µ *), transition temperature (T c ), isotope effect exponent (α) and interaction strength (N 0 V) for two metallic glasses, i.e. Be 90 Al 10 and Be 70 Al 30 , have been investigated by extending the BCSEliasberg-McMillan formalism for the metallic glass superconductors incorporating the effect of local field correction in dielectric screening functions which in turn become prominent in determining superconducting state parameters of the metallic glasses under consideration. We have employed eleven forms of dielectric screening functions -viz. Hartree, RPA, Modified Hubbard, Overhauser, Geldart -Vosko, Animalu, King -Cutler, SCS, Vashistha -Singwi, Ichimaru -Utsumi, and Farid et al. -in conjunction with Ashcroft's potential to predict superconducting state parameters. It is observed that the values of SSP are quite sensitive to the form of dielectric screening functions. In conclusion the present computed values of SSP for the RPA form of dielectric screening are in good agreement with the experimental values and other theoretical results for both glassy materials, which confirms the validity of the proposed formalism.

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