PROGRAM SUMMARY
Title of program:
GFCUBHEX
Catalogue identifier:
ADOD
Ref. in CPC:
137(2001)312
Distribution format: tar gzip file
Operating system: UNIX
High speed store required:
23MK words
Number of lines in distributed program, including test data, etc:
1081
Keywords:
Solid state physics, Defect, Cubic and hexagonal crystals, Elasticity,
Crystal defects, Green's function, Displacement field,
Atomistic simulation.
Programming language used: Fortran
Computer:
Dec Alpha workstation .
Nature of physical problem:
In linear elasticity theory, displacement fields caused by a point force
pattern can be expressed by the elastic Green's tensor function for an
infinite medium. It can be calculated using an exact single integral
solution [1]. However, the exact calculation is prohibitively expensive
for molecular dynamics simulations.
Method of solution
The single integral solution is used to tabulate the
orientation-dependent part of Green's tensor function. A linear
interpolation between grid points is used to calculate the Green's
tensor function and displacements in cubic and hexagonal crystals.
Transformation of orthogonal axes is employed for calculating the same
function in an arbitrary Cartesian coordinate system.
Restrictions:
The method is valid for all cubic and hexagonal crystals independent of
the magnitude of anisotropy.
Typical running time:
10^-6 second for all components of Green's function tensor and
displacement vector per atomic pair for a given input force; time taken
by the subroutine MATRIX to calculate once the set of grid points of
8 x 10^4 elements is about 20 s.
References:
[1] J.L. Synge, The Hypercircle in Mathematical Physics: A Method for
the Approximate Solution of Boundary-Value Problems, Cambridge Univ.
Press, Cambridge, 1957.