ELECTRONS, PHONONS AND THEIR INTERACTIONS IN METALS

Abstract

The matter embodied in this thesis contains the results of theoretical investigation to get insight into the behaviour of electrons and their interaction with phonans in the noble and simple polyvalent metals. In,order to Obtain electronic energy bands and the dynamical properties of quasiparticle excitations in the noble metals we have used the combined interpolation scheme and have incorporated the relativistic effects. The basis set contains five ti - binding functions and four orthogonalized plane waves (OPW). The spin-orbit interaction parameter, has, been set equal to its atomic value. The other parameters of the interpolation scheme have beenAetermined by adjusting them in such a manner that some of the measured Fermi-surface cross-sectional areas =Ai optical gaps are reproduced. The band structure so obtained niCely reproduces even those cross-sectional areas and optical gaps which were not used in the fitting procedure. Using this band structure density of states, Fermi wave vectors and Fermi velocities have been calculated. The comparison of these velocities with those obtained from deconvolution of cyclotron 'masses yields anisotropic electron-phonon renormalization factor. The Fermi-surface average of the renormalization factor that we have obtained is in good agreement with the experimental results.