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The lattice distortion produced by an isolated vacancy in aluminium and the noble metals has been calculated using a discrete lattice model which assumes non-equilibrium pairwise interactions extending out to second nearest neighbonrs. It is shown that, to first order, the relaxation volume associated with a vacancy can be expressed in t'erms of the elastic const,ants. For aluminium the asymptotic displacement field calculated from the lattice model is compared with the corresponding elasticity results.Es wird die durch cine isolierte Leerstclle in Aluminium und den Edelmetallen hervorgcrufene Gitterverzerrung mit einem diskreten Gittermodell berechnet, das paarweise Nichtglcichgcwichtswechselwirkungen anni mmt, die sich bis zu den zweitnachsten Nachbarn erstrecken. Es wird gezeigt, daR in erster Ordnung das mit einer Leerstclle verbundene Relaxationsvolumen mit den elastischen Konstanten ausgedruckt werden kann. Fur Aluminium wird das mit dem Gittermodell berechnete asymptot'ische Verzerrungsfeld mit entsprechenden Elastizitatswerten verglj chen. volunie enclosed by 8 increases by A I'"" = 1 u . n dS. If the continuum is finite there is an additional volume change which, unlike ATTm, arises froin the actual dilatation of the continuum. I n this case S J c where K is the bulk modulus.These concepts are widely used in crystal physics to discuss the properties of vacancies, interstitials, and substitutional atoms. However, the correspondence between continuum elasticity and the distortion of a crystal lattice is not complete ; for example, it is not possible from continuum considerations alone to specify the strength of the defect Gik and hence the volume change A V of the

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