Firstly we report here the results of a neutron scattering experiment on the phonon dispersion relations and phonon lifetimes in the alloy Pd0.84-Pt0.16 and compare them with those of an existing coherentpotential approximation calculation. We find good agreement in the frequency and shape of the resonance and remaining discrepancies are discussed. Then the results of existing or new CPA calculations for several other alloys are compared with experimental data on resonant and localized modes observed by other authors in the alloys. For these other systems in most cases a satisfactory agreement is found in the frequency position and shape of the resonance or of the localized mode, when the alloy characteristics are suited for a straightforward application of mass defect CPA. The relevance of these tests for CPA is also discussed.
Phonon modes in Pd-Pt and other substitutional alloys with large mass disorder
SACCHETTI, Francesco;
1978
Abstract
Firstly we report here the results of a neutron scattering experiment on the phonon dispersion relations and phonon lifetimes in the alloy Pd0.84-Pt0.16 and compare them with those of an existing coherentpotential approximation calculation. We find good agreement in the frequency and shape of the resonance and remaining discrepancies are discussed. Then the results of existing or new CPA calculations for several other alloys are compared with experimental data on resonant and localized modes observed by other authors in the alloys. For these other systems in most cases a satisfactory agreement is found in the frequency position and shape of the resonance or of the localized mode, when the alloy characteristics are suited for a straightforward application of mass defect CPA. The relevance of these tests for CPA is also discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
