The theoretical calculation of superconducting-state parameters (F p h), (Vc), and Z 0 C(F p h) estimates the phonon-mediated attractive electron-electron interaction in the metal; (Vc), the Coulomb pseudopotential, measures the effectiveness of the Coulomb repulsion in inhibiting superconductivity; and Zo, the quasiparticle mass (or energy) renormalization parameter, takes into account the many-body renormalization effects due to electron-phonon and Coulomb interactions] is undertaken for both nonsuperconductors and simple-metal (nontransition-metal) superconductors. The two questions faced are: why nonsuperconductors (alkali, alkaline-earth, and noble metals) are nonsuperconductors (this question arises from the startling prediction by Morel and Anderson that all metals should be superconductors); and whether better agreement can be achieved between theoretically estimated superconducting-state parameters and empirical parameters-better, e.g., than those of Pines and of Morel and Anderson. Our calculation is differentiated from that of Morel and Anderson first in using electron-phonon and Coulomb-interaction matrix elements between Bloch electron states, secondly in using for the electron-phonon matrix element the form suggested by Harrison for the orthogonalized-plane-wave form factor, and lastly in including the renormalization effects due to electron-phonon and Coulomb interactions. The renormalization due to Coulomb interaction is included by taking the values from the calculations by Rice. The Bloch electron states are calculated in a model in which the ionic core is replaced by a three-dimensional constant repulsive potential, and the wave function is determined in the spirit of the Wigner-Seitz approximation and first-order perturbation theory. The theoretically estimated parameters (F P h), {Vc) } and Zo are compared with the empirically estimated parameters. These are also compared with the parameters estimated by Garland. A good comparison-better than that of Morel and Anderson-is found between theoretical and empirical parameters. It is pointed out that if renormalization effects are included in the calculation by Morel and Anderson, then their apparently good comparison with empirical parameters does not remain so good. In the case of nonsuperconductors, we find that the phonon-mediated attractive interaction fails to dominate over the Coulomb repulsion, contrary to the conclusions of Morel and Anderson, and the effective interaction strength ((F p h)-{VQ))/ZQ, which is analogous to the BCS parameter NQV, is repulsive or very slightly attractive. The nonsuperconducting status is thus restored to alkali and alkalineearth metals.

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Calculations of the specific heat, Griineisen parameter, binding energy, and compressibility of sodium and potassium are made using a two-parameter model potential. The theoretical results are in qualitatively good agreement with available experimental results.Berechnungcn der spezifischen Warme, Griincisenparameter, Bindungsenergie und Kompressibilitat von Natrium und Kalium werden mit einem zweiparametrigen Modellpotential durchgefiihrt. Die theoretischen Ergebnisse befinden sich in qualitativ gutcr ubereinstimmung mit verfugbaren experimentellen Werten.

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A method is presented for the theoretical calculation of the logarithmic volume derivatives of the three superconducting state parameters, the phonon interaction parameter, the coulomb pseudopotential, and the energy renormalization parameter. The two representative cases of lead and aluminium have been studied. The initial linear drop of T, when plotted against change in volume, which is experimentally observed fact, is theoretically confirmed.Eine Methode zur theoretischen Berechnung der logarithmischen Volumenableitungen der drei Supraleitungszustandparameter, des Phononen-Wechselwirkungsparameters, des Coulomb-Pseudopotentials und des Energie-Renormierungsparameters, wird angegeben. Die beiden reprasentativen Fiille Blei und Aluminium wurden untersucht. Der lineare Anfangsabfall von 27, als Funktion der Volumeniinderung, der eine experimentell beobachtete Tatsache ist, wird theoretisch erkliirt.