Bildungsenergien von Punktdefekten in Metallen
Bildungsenergien von Punktdefekten in Metallen
This work represents a contribution to the problem of calculating point defect energetics in solids from first principles. Within the framework of spin density functional theory and based an the KKR's - Green's function method a formalism is developed to determine the total energy of a per...
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Personal Name(s): | Drittler, B. |
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Weinert, M. / Zeller, R. / Dederichs, Peter H. | |
Contributing Institute: |
Publikationen vor 2000; PRE-2000; Retrocat |
Imprint: |
Jülich
Kernforschungsanlage Jülich, Verlag
1988
|
Physical Description: |
84 p. |
Document Type: |
Report Book |
Research Program: |
ohne Topic |
Series Title: |
Berichte der Kernforschungsanlage Jülich
2205 |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
This work represents a contribution to the problem of calculating point defect energetics in solids from first principles. Within the framework of spin density functional theory and based an the KKR's - Green's function method a formalism is developed to determine the total energy of a perturbed cluster of atoms in an otherwise ideal crystal. The formalism takes advantage of the extremal properties of the total energy. As application the formation energies of vacancies in the-fcc metals CU, AG, NIand PD and the solution energies of 3d impurities in CU and NI are calculated. In general the experimentally observed trends of both quantities are correctly reproduced by the calculations. Quantitatively the calculated vacancy formation energies are systematically somewhat higher than the experimental values. Some important details of the total energy formalism will be shortly mentioned. Whereas the atomic potentials are approximated by spherically symmetric Wigner Seitz potentials the full nonsphericity of charge density within the Wigner Seitz spheres is taken into account, both for the double counting Coulomb term as well as for the exchange correllation energies. Since the Friedel's sum rule cannot be satiesfied exactly, the grand canonical energy functional is employed which is extremal alsofor non-particle-conserving variations. The single particle energies are calculated using an extension of Lloyd's formula to complex energies. Test calculations show that the appiication of Lloyd's formula ensures a fast shell by shell convergence. In all cases studied the self-consistent inclusion of the perturbation of the next neighbours is both sufficient as well as necessary to obtain reliable formation energies. |