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A first-principles prediction of the q dependence of the electronic susceptibility of YBa2Cu3O7 and the relation to experimentally observed phonon anomalies is presented.

The electronic structures of NiMnSb and CrO2 were calculated using a spin-polarised scalar relativistic linear muffin-tin orbital (LMTO) method. The self-consistent calculations were performed for the observed experimental lattice constants. Cubic NiMnSb (MgAgAs-type structure) and rutile-structure CrO2 are found to be 'half-metallic ferromagnets', i.e. they have a semiconducting gap in the minority-spin bands but metallic majority-spin bands. The calculated magnetic moments in both compounds were found to be in good agreement with the experimental values. The possibility of metastable magnetic states is investigated via extended Stoner factor calculations. It is shown that the position of the Fermi level with respect to the bandgap is extremely sensitive to the exchange-correlation potential approximation.

A simple technique for calculating the phonon-limited resistivity ( rho ph) of metals is described which is analogous to the Gaspari-Gyorffy method (1972) for calculating the electron-phonon coupling constant ( lambda ), rho ph and lambda are calculated for all 4d metals and silver. The HCP metals have been treated as cubic, as is common in calculations of lambda . For rho ph, however, this approach turns out to be too rough because it depends strongly on the average Fermi velocity which is very sensitive to crystal structure. In all transition metals investigated the superconducting and transport electron-phonon coupling constants are nearly equal, lambda approximately= lambda tr. Also nearly equal are their electronic parts, eta approximately= eta tr. The only exception is Pd, where eta tr is nearly 1.5 times larger than eta ; this is because the superconducting and transport properties of Pd are defined by different parts of the Fermi surface. Palladium is the only 4d metal where the Mott model of conductivity (s-d scattering) is valid.

The authors have calculated the optical properties (dielectric function, reflectivity and electron energy loss function) of 15 metals, including all the 4d series, some 3d metals and some noble and simple metals. The calculations are based on the LMTO band structure with optical matrix elements. The very good quantitative agreement with optical measurements provides an a posteriori justification of the use of local density functional method in the calculations of the dynamical response in metals and also allows an analysis of the general trends in optical properties from the electronic structure point of view.