The Korringa-Kohn-Rostoker method with projection potentials: exact result for the density

Area of Science:

• Condensed matter physics
• Materials science
• Computational physics

Background:

• The Korringa-Kohn-Rostoker (KKR) method is a powerful tool for electronic structure calculations.
• Numerical implementations of KKR often suffer from density normalization errors due to finite angular momentum expansions.

Purpose of the Study:

• To address and resolve the density normalization errors in the KKR multiple-scattering method.
• To develop a computationally efficient and accurate approach for electronic structure calculations.

Main Methods:

• Treating atomic potentials as non-local projection potentials in angular momentum space.
• Utilizing a finite subspace of spherical harmonics for the projection.
• Demonstrating that this approach yields exact density calculations.

Main Results:

• The proposed method effectively eliminates density normalization errors inherent in finite angular momentum expansions.
• Exact density can be computed without requiring infinite angular momentum sums.
• The accuracy can be arbitrarily improved by increasing the size of the spherical harmonic subspace.

Conclusions:

• The use of projection potentials offers an exact solution to the density normalization problem in KKR calculations.
• This method enhances the reliability and efficiency of electronic structure computations.
• The approach is general and can be applied to a wide range of materials.