Comparison of the projector augmented-wave, pseudopotential, and linearized augmented-plane-wave formalisms for density-functional calculations of solids

Abstract

The projector augmented-wave ͑PAW͒ method was developed by Blöchl as a method to accurately and efficiently calculate the electronic structure of materials within the framework of density-functional theory. It contains the numerical advantages of pseudopotential calculations while retaining the physics of all-electron calculations, including the correct nodal behavior of the valence-electron wave functions and the ability to include upper core states in addition to valence states in the self-consistent iterations. It uses many of the same ideas developed by Vanderbilt in his ''soft pseudopotential'' formalism and in earlier work by Blöchl in his ''generalized separable potentials,'' and has been successfully demonstrated for several interesting materials. We have developed a version of the PAW formalism for general use in structural and dynamical studies of materials. In the present paper, we investigate the accuracy of this implementation in comparison with corresponding results obtained using pseudopotential and linearized augmented-plane-wave ͑LAPW͒ codes. We present results of calculations for the cohesive energy, equilibrium lattice constant, and bulk modulus for several representative covalent, ionic, and metallic materials including diamond, silicon, SiC, CaF 2 , fcc Ca, and bcc V. With the exception of CaF 2 , for which core-electron polarization effects are important, the structural properties of these materials are represented equally well by the PAW, LAPW, and pseudopotential formalisms. ͓S0163-1829͑97͒00404-9͔

First-Principles Calculations of Schottky Barrier Heights of Monolayer Metal/6<I>H</I>-SiC{0001} Interfaces

“…We use the first-principles PAW method [25][26][27] based on the DFT within the generalized gradient approximation (GGA).…”

Real-space grid implementation of the projector augmented wave method

“…The PAW method has been implemented for plane waves by several groups. [27][28][29][30][31][32] We see the combination of real-space grid-based methods and the PAW method as an important step toward enabling larger calculations at a level of accuracy that is essentially all-electron in nature. There is a clear trend in electronic structure theory toward larger and more complex systems as for example nanostructures, large ͑bio-͒molecular complexes and extended defects in real materials-systems that all quickly challenge present-day high-accuracy DFT codes, which are typically limited to, at most, a few hundred atoms.…”

All-electron and pseudopotential study of the spin-polarization of the V(001) surface: LDA versus GGA

“…Subsequent calculations using all-electron [22][23][24][25] and/or pseudopotentials 23-26 methods, coincide pointing out the trend of GGA's to enhance magnetism of magnetic materials and susceptibilities of non magnetic materials when compared with results from analogous LSDA calculations. Singh and Ashkenazi 22 using the all-electron FLAPW method confirmed that bulk V and Pd are correctly predicted as paramagnetic by the PW91 GGA approximation, but conclude also that GGA's do not have greater precision than the LSDA for studying transition metals (TM) and specially for magnetic materials.…”