---
_id: '7481'
abstract:
- lang: eng
  text: The electronic band structures of hexagonal ZnO and cubic ZnS, ZnSe, and ZnTe
    compounds are determined within hybrid-density-functional theory and quasiparticle
    calculations. It is found that the band-edge energies calculated on the G0W0 (Zn
    chalcogenides) or GW (ZnO) level of theory agree well with experiment, while fully
    self-consistent QSGW calculations are required for the correct description of
    the Zn 3d bands. The quasiparticle band structures are used to calculate the linear
    response and second-harmonic-generation (SHG) spectra of the Zn–VI compounds.
    Excitonic effects in the optical absorption are accounted for within the Bethe–Salpeter
    approach. The calculated spectra are discussed in the context of previous experimental
    data and present SHG measurements for ZnO.
article_number: '215702'
article_type: original
author:
- first_name: Arthur
  full_name: Riefer, Arthur
  last_name: Riefer
- first_name: Nils
  full_name: Weber, Nils
  last_name: Weber
- first_name: Johannes
  full_name: Mund, Johannes
  last_name: Mund
- first_name: Dmitri R.
  full_name: Yakovlev, Dmitri R.
  last_name: Yakovlev
- first_name: Manfred
  full_name: Bayer, Manfred
  last_name: Bayer
- first_name: Arno
  full_name: Schindlmayr, Arno
  id: '458'
  last_name: Schindlmayr
  orcid: 0000-0002-4855-071X
- first_name: Cedrik
  full_name: Meier, Cedrik
  id: '20798'
  last_name: Meier
  orcid: https://orcid.org/0000-0002-3787-3572
- first_name: Wolf Gero
  full_name: Schmidt, Wolf Gero
  id: '468'
  last_name: Schmidt
  orcid: 0000-0002-2717-5076
citation:
  ama: 'Riefer A, Weber N, Mund J, et al. Zn–VI quasiparticle gaps and optical spectra
    from many-body calculations. <i>Journal of Physics: Condensed Matter</i>. 2017;29(21).
    doi:<a href="https://doi.org/10.1088/1361-648x/aa6b2a">10.1088/1361-648x/aa6b2a</a>'
  apa: 'Riefer, A., Weber, N., Mund, J., Yakovlev, D. R., Bayer, M., Schindlmayr,
    A., Meier, C., &#38; Schmidt, W. G. (2017). Zn–VI quasiparticle gaps and optical
    spectra from many-body calculations. <i>Journal of Physics: Condensed Matter</i>,
    <i>29</i>(21), Article 215702. <a href="https://doi.org/10.1088/1361-648x/aa6b2a">https://doi.org/10.1088/1361-648x/aa6b2a</a>'
  bibtex: '@article{Riefer_Weber_Mund_Yakovlev_Bayer_Schindlmayr_Meier_Schmidt_2017,
    title={Zn–VI quasiparticle gaps and optical spectra from many-body calculations},
    volume={29}, DOI={<a href="https://doi.org/10.1088/1361-648x/aa6b2a">10.1088/1361-648x/aa6b2a</a>},
    number={21215702}, journal={Journal of Physics: Condensed Matter}, publisher={IOP
    Publishing}, author={Riefer, Arthur and Weber, Nils and Mund, Johannes and Yakovlev,
    Dmitri R. and Bayer, Manfred and Schindlmayr, Arno and Meier, Cedrik and Schmidt,
    Wolf Gero}, year={2017} }'
  chicago: 'Riefer, Arthur, Nils Weber, Johannes Mund, Dmitri R. Yakovlev, Manfred
    Bayer, Arno Schindlmayr, Cedrik Meier, and Wolf Gero Schmidt. “Zn–VI Quasiparticle
    Gaps and Optical Spectra from Many-Body Calculations.” <i>Journal of Physics:
    Condensed Matter</i> 29, no. 21 (2017). <a href="https://doi.org/10.1088/1361-648x/aa6b2a">https://doi.org/10.1088/1361-648x/aa6b2a</a>.'
  ieee: 'A. Riefer <i>et al.</i>, “Zn–VI quasiparticle gaps and optical spectra from
    many-body calculations,” <i>Journal of Physics: Condensed Matter</i>, vol. 29,
    no. 21, Art. no. 215702, 2017, doi: <a href="https://doi.org/10.1088/1361-648x/aa6b2a">10.1088/1361-648x/aa6b2a</a>.'
  mla: 'Riefer, Arthur, et al. “Zn–VI Quasiparticle Gaps and Optical Spectra from
    Many-Body Calculations.” <i>Journal of Physics: Condensed Matter</i>, vol. 29,
    no. 21, 215702, IOP Publishing, 2017, doi:<a href="https://doi.org/10.1088/1361-648x/aa6b2a">10.1088/1361-648x/aa6b2a</a>.'
  short: 'A. Riefer, N. Weber, J. Mund, D.R. Yakovlev, M. Bayer, A. Schindlmayr, C.
    Meier, W.G. Schmidt, Journal of Physics: Condensed Matter 29 (2017).'
date_created: 2019-02-04T13:46:58Z
date_updated: 2025-12-16T11:07:33Z
ddc:
- '530'
department:
- _id: '287'
- _id: '295'
- _id: '296'
- _id: '230'
- _id: '429'
- _id: '35'
- _id: '15'
- _id: '170'
- _id: '429'
- _id: '27'
doi: 10.1088/1361-648x/aa6b2a
external_id:
  isi:
  - '000400093100001'
  pmid:
  - '28374685'
file:
- access_level: closed
  content_type: application/pdf
  creator: schindlm
  date_created: 2020-08-28T14:01:15Z
  date_updated: 2020-08-30T14:34:08Z
  description: © 2017 IOP Publishing Ltd
  file_id: '18574'
  file_name: Riefer_2017_J._Phys. _Condens._Matter_29_215702.pdf
  file_size: 2551657
  relation: main_file
  title: Zn–VI quasiparticle gaps and optical spectra from many-body calculations
file_date_updated: 2020-08-30T14:34:08Z
has_accepted_license: '1'
intvolume: '        29'
isi: '1'
issue: '21'
language:
- iso: eng
pmid: '1'
project:
- _id: '53'
  name: TRR 142
- _id: '55'
  name: TRR 142 - Project Area B
- _id: '66'
  name: TRR 142 - Subproject B1
- _id: '69'
  name: TRR 142 - Subproject B4
- _id: '52'
  name: Computing Resources Provided by the Paderborn Center for Parallel Computing
publication: 'Journal of Physics: Condensed Matter'
publication_identifier:
  eissn:
  - 1361-648X
  issn:
  - 0953-8984
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
status: public
title: Zn–VI quasiparticle gaps and optical spectra from many-body calculations
type: journal_article
user_id: '16199'
volume: 29
year: '2017'
...
---
_id: '10030'
abstract:
- lang: eng
  text: The vibrational properties of stoichiometric LiNbO3 are analyzed within density-functional
    perturbation theory in order to obtain the complete phonon dispersion of the material.
    The phonon density of states of the ferroelectric (paraelectric) phase shows two
    (one) distinct band gaps separating the high-frequency (~800 cm−1) optical branches
    from the continuum of acoustic and lower optical phonon states. This result leads
    to specific heat capacites in close agreement with experimental measurements in
    the range 0–350 K and a Debye temperature of 574 K. The calculated zero-point
    renormalization of the electronic Kohn–Sham eigenvalues reveals a strong dependence
    on the phonon wave vectors, especially near Γ. Integrated over all phonon modes,
    our results indicate a vibrational correction of the electronic band gap of 0.41 eV
    at 0 K, which is in excellent agreement with the extrapolated temperature-dependent
    measurements.
article_number: '385402'
article_type: original
author:
- first_name: Michael
  full_name: Friedrich, Michael
  last_name: Friedrich
- first_name: Arthur
  full_name: Riefer, Arthur
  last_name: Riefer
- first_name: Simone
  full_name: Sanna, Simone
  last_name: Sanna
- first_name: Wolf Gero
  full_name: Schmidt, Wolf Gero
  id: '468'
  last_name: Schmidt
  orcid: 0000-0002-2717-5076
- first_name: Arno
  full_name: Schindlmayr, Arno
  id: '458'
  last_name: Schindlmayr
  orcid: 0000-0002-4855-071X
citation:
  ama: 'Friedrich M, Riefer A, Sanna S, Schmidt WG, Schindlmayr A. Phonon dispersion
    and zero-point renormalization of LiNbO3 from density-functional perturbation
    theory. <i>Journal of Physics: Condensed Matter</i>. 2015;27(38). doi:<a href="https://doi.org/10.1088/0953-8984/27/38/385402">10.1088/0953-8984/27/38/385402</a>'
  apa: 'Friedrich, M., Riefer, A., Sanna, S., Schmidt, W. G., &#38; Schindlmayr, A.
    (2015). Phonon dispersion and zero-point renormalization of LiNbO3 from density-functional
    perturbation theory. <i>Journal of Physics: Condensed Matter</i>, <i>27</i>(38),
    Article 385402. <a href="https://doi.org/10.1088/0953-8984/27/38/385402">https://doi.org/10.1088/0953-8984/27/38/385402</a>'
  bibtex: '@article{Friedrich_Riefer_Sanna_Schmidt_Schindlmayr_2015, title={Phonon
    dispersion and zero-point renormalization of LiNbO3 from density-functional perturbation
    theory}, volume={27}, DOI={<a href="https://doi.org/10.1088/0953-8984/27/38/385402">10.1088/0953-8984/27/38/385402</a>},
    number={38385402}, journal={Journal of Physics: Condensed Matter}, publisher={IOP
    Publishing}, author={Friedrich, Michael and Riefer, Arthur and Sanna, Simone and
    Schmidt, Wolf Gero and Schindlmayr, Arno}, year={2015} }'
  chicago: 'Friedrich, Michael, Arthur Riefer, Simone Sanna, Wolf Gero Schmidt, and
    Arno Schindlmayr. “Phonon Dispersion and Zero-Point Renormalization of LiNbO3
    from Density-Functional Perturbation Theory.” <i>Journal of Physics: Condensed
    Matter</i> 27, no. 38 (2015). <a href="https://doi.org/10.1088/0953-8984/27/38/385402">https://doi.org/10.1088/0953-8984/27/38/385402</a>.'
  ieee: 'M. Friedrich, A. Riefer, S. Sanna, W. G. Schmidt, and A. Schindlmayr, “Phonon
    dispersion and zero-point renormalization of LiNbO3 from density-functional perturbation
    theory,” <i>Journal of Physics: Condensed Matter</i>, vol. 27, no. 38, Art. no.
    385402, 2015, doi: <a href="https://doi.org/10.1088/0953-8984/27/38/385402">10.1088/0953-8984/27/38/385402</a>.'
  mla: 'Friedrich, Michael, et al. “Phonon Dispersion and Zero-Point Renormalization
    of LiNbO3 from Density-Functional Perturbation Theory.” <i>Journal of Physics:
    Condensed Matter</i>, vol. 27, no. 38, 385402, IOP Publishing, 2015, doi:<a href="https://doi.org/10.1088/0953-8984/27/38/385402">10.1088/0953-8984/27/38/385402</a>.'
  short: 'M. Friedrich, A. Riefer, S. Sanna, W.G. Schmidt, A. Schindlmayr, Journal
    of Physics: Condensed Matter 27 (2015).'
date_created: 2019-05-29T08:41:18Z
date_updated: 2025-12-05T10:00:42Z
ddc:
- '530'
department:
- _id: '295'
- _id: '296'
- _id: '230'
- _id: '429'
- _id: '15'
- _id: '35'
- _id: '27'
doi: 10.1088/0953-8984/27/38/385402
external_id:
  isi:
  - '000362549700004'
  pmid:
  - '26337951'
file:
- access_level: closed
  content_type: application/pdf
  creator: schindlm
  date_created: 2020-08-28T14:24:23Z
  date_updated: 2020-08-30T14:46:56Z
  description: © 2015 IOP Publishing Ltd
  file_id: '18578'
  file_name: Friedrich_2015_J._Phys. _Condens._Matter_27_385402.pdf
  file_size: 1793430
  relation: main_file
  title: Phonon dispersion and zero-point renormalization of LiNbO3 from density-functional
    perturbation theory
file_date_updated: 2020-08-30T14:46:56Z
has_accepted_license: '1'
intvolume: '        27'
isi: '1'
issue: '38'
language:
- iso: eng
pmid: '1'
project:
- _id: '52'
  name: Computing Resources Provided by the Paderborn Center for Parallel Computing
- _id: '53'
  name: TRR 142
- _id: '55'
  name: TRR 142 - Project Area B
- _id: '69'
  name: TRR 142 - Subproject B4
- _id: '52'
  name: Computing Resources Provided by the Paderborn Center for Parallel Computing
publication: 'Journal of Physics: Condensed Matter'
publication_identifier:
  eissn:
  - 1361-648X
  issn:
  - 0953-8984
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
status: public
title: Phonon dispersion and zero-point renormalization of LiNbO3 from density-functional
  perturbation theory
type: journal_article
user_id: '16199'
volume: 27
year: '2015'
...
---
_id: '18542'
abstract:
- lang: eng
  text: 'We present recent advances in numerical implementations of hybrid functionals
    and the GW approximation within the full-potential linearized augmented-plane-wave
    (FLAPW) method. The former is an approximation for the exchange–correlation contribution
    to the total energy functional in density-functional theory, and the latter is
    an approximation for the electronic self-energy in the framework of many-body
    perturbation theory. All implementations employ the mixed product basis, which
    has evolved into a versatile basis for the products of wave functions, describing
    the incoming and outgoing states of an electron that is scattered by interacting
    with another electron. It can thus be used for representing the nonlocal potential
    in hybrid functionals as well as the screened interaction and related quantities
    in GW calculations. In particular, the six-dimensional space integrals of the
    Hamiltonian exchange matrix elements (and exchange self-energy) decompose into
    sums over vector–matrix–vector products, which can be evaluated easily. The correlation
    part of the GW self-energy, which contains a time or frequency dependence, is
    calculated on the imaginary frequency axis with a subsequent analytic continuation
    to the real axis or, alternatively, by a direct frequency convolution of the Green
    function G and the dynamically screened Coulomb interaction W along a contour
    integration path that avoids the poles of the Green function. Hybrid-functional
    and GW calculations are notoriously computationally expensive. We present a number
    of tricks that reduce the computational cost considerably, including the use of
    spatial and time-reversal symmetries, modifications of the mixed product basis
    with the aim to optimize it for the correlation self-energy and another modification
    that makes the Coulomb matrix sparse, analytic expansions of the interaction potentials
    around the point of divergence at k=0, and a nested density and density-matrix
    convergence scheme for hybrid-functional calculations. We show CPU timings for
    prototype semiconductors and illustrative results for GdN and ZnO. '
article_number: '293201'
article_type: review
author:
- first_name: Christoph
  full_name: Friedrich, Christoph
  last_name: Friedrich
- first_name: Markus
  full_name: Betzinger, Markus
  last_name: Betzinger
- first_name: Martin
  full_name: Schlipf, Martin
  last_name: Schlipf
- first_name: Stefan
  full_name: Blügel, Stefan
  last_name: Blügel
- first_name: Arno
  full_name: Schindlmayr, Arno
  id: '458'
  last_name: Schindlmayr
  orcid: 0000-0002-4855-071X
citation:
  ama: 'Friedrich C, Betzinger M, Schlipf M, Blügel S, Schindlmayr A. Hybrid functionals
    and GW approximation in the FLAPW method. <i>Journal of Physics: Condensed Matter</i>.
    2012;24(29). doi:<a href="https://doi.org/10.1088/0953-8984/24/29/293201">10.1088/0953-8984/24/29/293201</a>'
  apa: 'Friedrich, C., Betzinger, M., Schlipf, M., Blügel, S., &#38; Schindlmayr,
    A. (2012). Hybrid functionals and GW approximation in the FLAPW method. <i>Journal
    of Physics: Condensed Matter</i>, <i>24</i>(29), Article 293201. <a href="https://doi.org/10.1088/0953-8984/24/29/293201">https://doi.org/10.1088/0953-8984/24/29/293201</a>'
  bibtex: '@article{Friedrich_Betzinger_Schlipf_Blügel_Schindlmayr_2012, title={Hybrid
    functionals and GW approximation in the FLAPW method}, volume={24}, DOI={<a href="https://doi.org/10.1088/0953-8984/24/29/293201">10.1088/0953-8984/24/29/293201</a>},
    number={29293201}, journal={Journal of Physics: Condensed Matter}, publisher={IOP
    Publishing}, author={Friedrich, Christoph and Betzinger, Markus and Schlipf, Martin
    and Blügel, Stefan and Schindlmayr, Arno}, year={2012} }'
  chicago: 'Friedrich, Christoph, Markus Betzinger, Martin Schlipf, Stefan Blügel,
    and Arno Schindlmayr. “Hybrid Functionals and GW Approximation in the FLAPW Method.”
    <i>Journal of Physics: Condensed Matter</i> 24, no. 29 (2012). <a href="https://doi.org/10.1088/0953-8984/24/29/293201">https://doi.org/10.1088/0953-8984/24/29/293201</a>.'
  ieee: 'C. Friedrich, M. Betzinger, M. Schlipf, S. Blügel, and A. Schindlmayr, “Hybrid
    functionals and GW approximation in the FLAPW method,” <i>Journal of Physics:
    Condensed Matter</i>, vol. 24, no. 29, Art. no. 293201, 2012, doi: <a href="https://doi.org/10.1088/0953-8984/24/29/293201">10.1088/0953-8984/24/29/293201</a>.'
  mla: 'Friedrich, Christoph, et al. “Hybrid Functionals and GW Approximation in the
    FLAPW Method.” <i>Journal of Physics: Condensed Matter</i>, vol. 24, no. 29, 293201,
    IOP Publishing, 2012, doi:<a href="https://doi.org/10.1088/0953-8984/24/29/293201">10.1088/0953-8984/24/29/293201</a>.'
  short: 'C. Friedrich, M. Betzinger, M. Schlipf, S. Blügel, A. Schindlmayr, Journal
    of Physics: Condensed Matter 24 (2012).'
date_created: 2020-08-28T10:14:44Z
date_updated: 2025-12-16T08:09:33Z
ddc:
- '530'
department:
- _id: '296'
- _id: '35'
- _id: '15'
- _id: '170'
- _id: '230'
doi: 10.1088/0953-8984/24/29/293201
external_id:
  isi:
  - '000306270700001'
  pmid:
  - '22773268'
file:
- access_level: closed
  content_type: application/pdf
  creator: schindlm
  date_created: 2020-08-28T14:30:29Z
  date_updated: 2020-08-30T15:00:14Z
  description: © 2012 IOP Publishing Ltd
  file_id: '18580'
  file_name: Friedrich_2012_J._Phys. _Condens._Matter_24_293201.pdf
  file_size: 1059896
  relation: main_file
  title: Hybrid functionals and GW approximation in the FLAPW method
file_date_updated: 2020-08-30T15:00:14Z
has_accepted_license: '1'
intvolume: '        24'
isi: '1'
issue: '29'
language:
- iso: eng
pmid: '1'
publication: 'Journal of Physics: Condensed Matter'
publication_identifier:
  eissn:
  - 1361-648X
  issn:
  - 0953-8984
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
status: public
title: Hybrid functionals and GW approximation in the FLAPW method
type: journal_article
user_id: '16199'
volume: 24
year: '2012'
...
---
_id: '18624'
abstract:
- lang: eng
  text: We investigate the performance of the GW approximation by comparison to exact
    results for small model systems. The role of the chemical potentials in Dyson's
    equation as well as the consequences of numerical resonance broadening are examined,
    and we show how a proper treatment can improve computational implementations of
    many-body perturbation theory in general. Exchange-only and GW calculations are
    performed over a wide range of fractional band fillings and correlation strengths.
    We thus identify the physical situations where these schemes are applicable.
article_type: original
author:
- first_name: Thomas Joachim
  full_name: Pollehn, Thomas Joachim
  last_name: Pollehn
- first_name: Arno
  full_name: Schindlmayr, Arno
  id: '458'
  last_name: Schindlmayr
  orcid: 0000-0002-4855-071X
- first_name: Rex William
  full_name: Godby, Rex William
  last_name: Godby
citation:
  ama: 'Pollehn TJ, Schindlmayr A, Godby RW. Assessment of the GW approximation using
    Hubbard chains. <i>Journal of Physics: Condensed Matter</i>. 1998;10(6):1273-1283.
    doi:<a href="https://doi.org/10.1088/0953-8984/10/6/011">10.1088/0953-8984/10/6/011</a>'
  apa: 'Pollehn, T. J., Schindlmayr, A., &#38; Godby, R. W. (1998). Assessment of
    the GW approximation using Hubbard chains. <i>Journal of Physics: Condensed Matter</i>,
    <i>10</i>(6), 1273–1283. <a href="https://doi.org/10.1088/0953-8984/10/6/011">https://doi.org/10.1088/0953-8984/10/6/011</a>'
  bibtex: '@article{Pollehn_Schindlmayr_Godby_1998, title={Assessment of the GW approximation
    using Hubbard chains}, volume={10}, DOI={<a href="https://doi.org/10.1088/0953-8984/10/6/011">10.1088/0953-8984/10/6/011</a>},
    number={6}, journal={Journal of Physics: Condensed Matter}, publisher={IOP Publishing},
    author={Pollehn, Thomas Joachim and Schindlmayr, Arno and Godby, Rex William},
    year={1998}, pages={1273–1283} }'
  chicago: 'Pollehn, Thomas Joachim, Arno Schindlmayr, and Rex William Godby. “Assessment
    of the GW Approximation Using Hubbard Chains.” <i>Journal of Physics: Condensed
    Matter</i> 10, no. 6 (1998): 1273–83. <a href="https://doi.org/10.1088/0953-8984/10/6/011">https://doi.org/10.1088/0953-8984/10/6/011</a>.'
  ieee: 'T. J. Pollehn, A. Schindlmayr, and R. W. Godby, “Assessment of the GW approximation
    using Hubbard chains,” <i>Journal of Physics: Condensed Matter</i>, vol. 10, no.
    6, pp. 1273–1283, 1998, doi: <a href="https://doi.org/10.1088/0953-8984/10/6/011">10.1088/0953-8984/10/6/011</a>.'
  mla: 'Pollehn, Thomas Joachim, et al. “Assessment of the GW Approximation Using
    Hubbard Chains.” <i>Journal of Physics: Condensed Matter</i>, vol. 10, no. 6,
    IOP Publishing, 1998, pp. 1273–83, doi:<a href="https://doi.org/10.1088/0953-8984/10/6/011">10.1088/0953-8984/10/6/011</a>.'
  short: 'T.J. Pollehn, A. Schindlmayr, R.W. Godby, Journal of Physics: Condensed
    Matter 10 (1998) 1273–1283.'
date_created: 2020-08-28T21:58:46Z
date_updated: 2022-11-11T06:58:18Z
ddc:
- '530'
doi: 10.1088/0953-8984/10/6/011
extern: '1'
external_id:
  arxiv:
  - cond-mat/9711120
  isi:
  - '000072104000011'
file:
- access_level: closed
  content_type: application/pdf
  creator: schindlm
  date_created: 2020-08-28T21:59:59Z
  date_updated: 2020-08-30T16:19:49Z
  description: © 1998 IOP Publishing Ltd
  file_id: '18625'
  file_name: Thomas_J_Pollehn_1998_J._Phys. _Condens._Matter_10_011.pdf
  file_size: 226847
  relation: main_file
  title: Assessment of the GW approximation using Hubbard chains
file_date_updated: 2020-08-30T16:19:49Z
has_accepted_license: '1'
intvolume: '        10'
isi: '1'
issue: '6'
language:
- iso: eng
page: 1273-1283
publication: 'Journal of Physics: Condensed Matter'
publication_identifier:
  eissn:
  - 1361-648X
  issn:
  - 0953-8984
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
status: public
title: Assessment of the GW approximation using Hubbard chains
type: journal_article
user_id: '458'
volume: 10
year: '1998'
...