Frequently Asked Questions

General

Citation: how should I cite GPAW?

If you find GPAW useful in your research please cite the original reference:

J. J. Mortensen, L. B. Hansen , and K. W. Jacobsen
Physical Review B, Vol. 71, 035109, 2005

and the major GPAW review:

J. Enkovaara, C. Rostgaard, J. J. Mortensen et al.
J. Phys.: Condens. Matter 22, 253202 (2010)

together with ASE citation (see How should I cite ASE?).

If you are using the time-dependent DFT part of the code, please cite also:

M. Walter, H. Häkkinen, L. Lehtovaara, M. Puska, J. Enkovaara, C. Rostgaard and J. J. Mortensen
Journal of Chemical Physics, Vol. 128, 244101, 2008

If you use the localized basis set, please cite also:

A. H. Larsen, M. Vanin, J. J. Mortensen, K. S. Thygesen, and K. W. Jacobsen
Physical Review B, Vol. 80, 195112, 2009

If you use the Linear dielectric response of an extended system, please cite also:

Jun Yan, Jens. J. Mortensen, Karsten W. Jacobsen, and Kristian S. Thygesen
Physical Review B Vol. 83, 245122, 2011

If you use the Quasi-particle spectrum in the GW approximation: tutorial, please cite also:

F. Hüser, T. Olsen, and K. S. Thygesen
Physical Review B Vol. 87, 235132, 2013

If you use the Continuum Solvent Model (CSM), please cite also:

A. Held and M. Walter
The Journal of Chemical Physics Vol. 141, 174108, 2014

BibTex (doc/GPAW.bib):

@article{ISI:000257284000004,
Author = {Walter, Michael and H{\"a}kkinen, Hannu and Lehtovaara, Lauri and Puska,
   Martti and Enkovaara, Jussi and Rostgaard, Carsten and Mortensen, Jens
   Jorgen},
Title = {Time-dependent density-functional theory in the projector
   augmented-wave method},
JournalFull = {JOURNAL OF CHEMICAL PHYSICS},
Year = {2008},
Volume = {128},
Number = {24},
Pages = {244101},
Month = {JUN 28},
Abstract = {We present the implementation of the time-dependent density-functional
   theory both in linear-response and in time-propagation formalisms using
   the projector augmented-wave method in real-space grids. The two
   technically very different methods are compared in the linear-response
   regime where we found perfect agreement in the calculated
   photoabsorption spectra. We discuss the strengths and weaknesses of the
   two methods as well as their convergence properties. We demonstrate
   different applications of the methods by calculating excitation
   energies and excited state Born-Oppenheimer potential surfaces for a
   set of atoms and molecules with the linear-response method and by
   calculating nonlinear emission spectra using the time-propagation
   method. (C) 2008 American Institute of Physics.},
Publisher = {AMER INST PHYSICS},
Address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1,
   MELVILLE, NY 11747-4501 USA},
Language = {English},
DOI = {10.1063/1.2943138},
Article-Number = {244101},
ISSN = {0021-9606},
Keywords-Plus = {ELECTRONIC EXCITATIONS; RESPONSE THEORY; REAL-TIME; APPROXIMATION;
   CLUSTERS; SPECTRA; EQUATIONS; EXCHANGE; ATOMS},
Subject-Category = {Physics, Atomic, Molecular \& Chemical},
Number-of-Cited-References = {46},
Journal-ISO = {J. Chem. Phys.},
Journal = {J. Chem. Phys.},
Unique-ID = {ISI:000257284000004},
}

@article{ISI:000226735900040,
Author = {J. J. Mortensen and L. B. Hansen and K. W. Jacobsen},
Title = {Real-space grid implementation of the projector augmented wave method},
JournalFull = {PHYSICAL REVIEW B},
Year = {2005},
Volume = {71},
Number = {3},
Pages = {035109},
Month = {JAN},
Abstract = {A grid-based real-space implementation of the projector augmented wave
   (PAW) method of Blochl {[}Phys. Rev. B 50, 17953 (1994)] for density
   functional theory (DFT) calculations is presented. The use of uniform
   three-dimensional (3D) real-space grids for representing wave
   functions, densities, and potentials allows for flexible boundary
   conditions, efficient multigrid algorithms for solving Poisson and
   Kohn-Sham equations, and efficient parallelization using simple
   real-space domain-decomposition. We use the PAW method to perform
   all-electron calculations in the frozen core approximation, with smooth
   valence wave functions that can be represented on relatively coarse
   grids. We demonstrate the accuracy of the method by calculating the
   atomization energies of 20 small molecules, and the bulk modulus and
   lattice constants of bulk aluminum. We show that the approach in terms
   of computational efficiency is comparable to standard plane-wave
   methods, but the memory requirements are higher.},
Publisher = {AMERICAN PHYSICAL SOC},
Address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},
Language = {English},
DOI = {10.1103/PhysRevB.71.035109},
Article-Number = {035109},
ISSN = {1098-0121},
Keywords-Plus = {ELECTRONIC-STRUCTURE CALCULATIONS; DENSITY-FUNCTIONAL-THEORY;
   TOTAL-ENERGY CALCULATIONS; GENERALIZED GRADIENT APPROXIMATION; INITIO
   MOLECULAR-DYNAMICS; FREE DFT IMPLEMENTATION; AB-INITIO;
   FINITE-DIFFERENCE; ULTRASOFT PSEUDOPOTENTIALS; MULTIGRID METHODS},
Subject-Category = {Physics, Condensed Matter},
Number-of-Cited-References = {53},
Journal-ISO = {Phys. Rev. B},
Journal = {Phys. Rev. B},
Unique-ID = {ISI:000226735900040},
}


@Article{PhysRevB.80.195112,
  title = {Localized atomic basis set in the projector augmented wave method},
  author = {Larsen, A. H. and Vanin, M.  and Mortensen, J. J. and Thygesen, K. S. and Jacobsen, K. W.},
  journal = {Phys. Rev. B},
  volume = {80},
  number = {19},
  pages = {195112},
  numpages = {10},
  year = {2009},
  month = {Nov},
  doi = {10.1103/PhysRevB.80.195112},
  publisher = {American Physical Society}
  Abstract = {We present an implementation of localized atomic-orbital
basis sets in the projector augmented wave (PAW) formalism within the
density-functional theory. The implementation in the real-space GPAW
code provides a complementary basis set to the accurate but
computationally more demanding grid representation. The possibility to
switch seamlessly between the two representations implies that
simulations employing the local basis can be fine tuned at the end of
the calculation by switching to the grid, thereby combining the
strength of the two representations for optimal performance. The
implementation is tested by calculating atomization energies and
equilibrium bulk properties of a variety of molecules and solids,
comparing to the grid results. Finally, it is demonstrated how a
grid-quality structure optimization can be performed with
significantly reduced computational effort by switching between the
grid and basis representations.}
}

@Article{PhysRevB.83.245122,
  title = {Linear density response function in the projector augmented wave method: Applications to solids, surfaces, and interfaces},
  author = {Yan, Jun  and Mortensen, Jens. J. and Jacobsen, Karsten W. and Thygesen, Kristian S.},
  journal = {Phys. Rev. B},
  volume = {83},
  number = {24},
  pages = {245122},
  numpages = {10},
  year = {2011},
  month = {Jun},
  doi = {10.1103/PhysRevB.83.245122},
  publisher = {American Physical Society}
}


@article{PhysRevB.87.235132,
  title = {Quasiparticle GW calculations for solids, molecules, and two-dimensional materials},
  author = {H\"user, Falco and Olsen, Thomas and Thygesen, Kristian S.},
  journal = {Phys. Rev. B},
  volume = {87},
  issue = {23},
  pages = {235132},
  numpages = {14},
  year = {2013},
  month = {Jun},
  publisher = {American Physical Society},
  doi = {10.1103/PhysRevB.87.235132},
  url = {http://link.aps.org/doi/10.1103/PhysRevB.87.235132}
}

@article{JChemPhys.141.174108,
   author = {Held, Alexander and Walter, Michael},
   title = {Simplified continuum solvent model with a smooth cavity based on volumetric data},
   journal = {J. Chem. Phys.},
   year = {2014},
   volume = {141},
   number = {17}, 
   pages = {174108},
   url = {http://scitation.aip.org/content/aip/journal/jcp/141/17/10.1063/1.4900838},
   doi = {10.1063/1.4900838}
}

How do you pronounce GPAW?

In English: “geepaw” with a long “a”.

In Danish: Først bogstavet “g”, derefter “pav”: “g-pav”.

In Finnish: supisuomalaisittain “kee-pav”.

In Polish: “gyeh” jak “Gie”rek, “pav” jak paw: “gyeh-pav”.

Compiling the C-code

For architecture dependent settings see the Platforms and architectures page.

Compilation of the C part failed:

[~]$ python2.4 setup.py build_ext
building '_gpaw' extension
pgcc -fno-strict-aliasing -DNDEBUG -O2 -g -pipe -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -m64 -D_GNU_SOURCE -fPIC -fPIC -I/usr/include/python2.4 -c c/localized_functions.c -o build/temp.linux-x86_64-2.4/c/localized_functions.o -Wall -std=c99
pgcc-Warning-Unknown switch: -fno-strict-aliasing
PGC-S-0040-Illegal use of symbol, _Complex (/usr/include/bits/cmathcalls.h: 54)

You are probably using another compiler, than was used for compiling python. Undefine the environment variables CC, CFLAGS and LDFLAGS with:

# sh/bash users:
unset CC; unset CFLAGS; unset LDFLAGS
# csh/tcsh users:
unsetenv CC; unsetenv CFLAGS; unsetenv LDFLAGS

and try again.

Calculation does not converge

Consult the Convergence Issues page.

Poisson solver did not converge!

If you are doing a spin-polarized calculation for an isolated molecule, then you should set the Fermi temperature to a low value.

You can also try to set the number of grid points to be divisible by 8. Consult the Notes on performance page.

Tests fail!

Please report the failing test as described on Run the tests.