Conclusions
The developed version of the augmented plane wave method yields eigenvalues and eigenfunctions with higher accuracy than the standard LAPW, preserving its computational efficiency.
The approximation of the exact radial solution by the Taylor expansion involving also the second energy derivative of the radial function, except for the first derivative, has two advantages. First, the energy dependence of the logarithmic derivatives atr=R is better described and, therefore, the method is less sensitive to the choice of the centre of expansionE 0 or, equivalently, acceptably accurate eigenvalues are obtained for the broader energy region aroundE 0. The other and probably more important advantage is that the approximate radial solutions are remarkably closer to the exact radial functions inside the muffin-tin sphere. This can be of use when evaluating the measurable quantities depending on the wave functions.
Similar content being viewed by others
References
Andersen O. K.: Phys. Rev. B12 (1975) 2060.
Koelling D. D., Arbman G. O.: J. Phys. F5 (1975) 2041.
Petrů J.: private communication.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Smrčka, L. Linearized augmented plane wave method utilizing the quadratic energy expansion of radial wave functions. Czech J Phys 34, 694–704 (1984). https://doi.org/10.1007/BF01589865
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01589865