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Manuscript Title: Computation of the anisotropic cubic elastic Green's tensor function and the elastic energy coefficients of point defects in crystals.
Authors: R.K. Leutz, R. Bauer
Program title: ANISCO
Catalogue identifier: ACKL_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 11(1976)339
Programming language: Algol.
Computer: TELEFUNKEN TR 440.
Operating system: BS 3.
RAM: 10K words
Word size: 48
Keywords: Solid state physics, Elasticity, Defect point, Energy elastic, Volume change, Green's function, Kroener's formula, Infinite medium, Cubic symmetry.
Classification: 7.1.

Nature of problem:
The elastic properties of a medium can be expressed by the elastic fundamental integral (elastic Green's tensor function for the infinite medium). It can be calculated exactly only for isotropic and hexagonal symmetry, for all others (e.g. cubic) approximations must be used.

Solution method:
Kroener gave an expansion of Green's function in spherical harmonics, which has the advantage of being differentiable, so that the physically important first and second derivatives can be calculated. Our program calculates the expansion coefficients of Green's function and its first and second derivatives; with them the coefficients of the elastic energy and the volume change of a point defect were obtained.

The expansion in spherical harmoincs is valid for all crystal structures, but our program is restricted to cubic symmetry.

Running time:
The running time depends on the degree of anisotropy of the medium and on the accuracy of the results. With a relative accuracy of 10**-3 the computing time of the test run for Cu was 156 s.