Enhancements to the GW space-time method
|Title||Enhancements to the GW space-time method|
|Publication Type||Palaiseau Article|
|Author Address|| |
Steinbeck, L (Reprint Author), Inst Festkorper & Werkstofforsch, Postfach 270016, D-01171 Dresden, Germany. Univ York, Dept Phys, York YO1 5DD, N Yorkshire, England. Univ Valladolid, Dept Fis Teor, E-47011 Valladolid, Spain. Ecole Polytech, Solides Irradies Lab, UMR 7642 CNRS, CEA,CERAM, F-91128 Palaiseau, France. Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England.
|Steinbeck, L, Rubio, A, Reining, L, Torrent, M, White, ID, Godby, RW|
|Publisher||ELSEVIER SCIENCE BV|
|Year of Publication||2000|
|Journal||Computer Physics Commun.|
|Type of Work||Article|
|Keywords||electronic structure; quasiparticle energies; self-energy calculations; GW approximation, paper|
We describe the following new features which significantly enhance the power of the recently developed real-space imaginary-time GW scheme (Rieger et al., Comp. Phys. Commun. 117 (1999) 211) for the calculation of self-energies and related quantities of solids: (i) to fit the smoothly decaying time/energy tails of the dynamically screened Coulomb interaction and other quantities to model functions, treating only the remaining time/energy region close to zero numerically and performing the Fourier transformation from time to energy and vice versa by a combination of analytic integration of the tails and Gauss-Legendre quadrature of the remaining part and (ii) to accelerate the convergence of the band sum in the calculation of the Green's function by replacing higher unoccupied eigenstates by free electron states (plane waves). These improvements make the calculation of larger systems (surfaces, clusters, defects etc.) accessible. (C) 2000 Elsevier Science B.V. All rights reserved.