Vibrational properties of phonons in random binary alloys:: An augmented space recursive technique in the k representation -: art. no. 024205

We present here an augmented space recursive technique in the k representation which include diagonal, off-diagonal, and the environmental disorder explicitly: an analytic, translationally invariant, multiple-scattering theory for phonons in random binary alloys. We propose the augmented space recursion as a computationally fast and accurate technique which will incorporate configuration fluctuations over a large local environment. We apply the formalism to Ni55Pd45, Ni88Cr12, and Ni50Pt50 alloys which is not a random choice. Numerical results on spectral functions, coherent structure factors, dispersion curves, and disordered induced full widths at half maximum are presented. Finally the results are compared with the recent itinerant coherent potential approximation and also with experiments.