Hyppää sisältöön
    • FI
    • ENG
  • FI
  • /
  • EN
OuluREPO – Oulun yliopiston julkaisuarkisto / University of Oulu repository
Näytä viite 
  •   OuluREPO etusivu
  • Oulun yliopisto
  • Avoin saatavuus
  • Näytä viite
  •   OuluREPO etusivu
  • Oulun yliopisto
  • Avoin saatavuus
  • Näytä viite
JavaScript is disabled for your browser. Some features of this site may not work without it.

Quantum-classical calculations of X-ray photoelectron spectra of polymers : polymethyl methacrylate revisited

Löytynoja, T.; Harczuk, I.; Jänkälä, K.; Vahtras, O.; Ågren, H. (2017-03-01)

 
Avaa tiedosto
nbnfi-fe201706127119.pdf (4.226Mt)
nbnfi-fe201706127119_meta.xml (38.23Kt)
nbnfi-fe201706127119_solr.xml (37.22Kt)
Lataukset: 

URL:
https://doi.org/10.1063/1.4978941

Löytynoja, T.
Harczuk, I.
Jänkälä, K.
Vahtras, O.
Ågren, H.
American Institute of Physics
01.03.2017

Quantum-classical calculations of X-ray photoelectron spectra of polymers—Polymethyl methacrylate revisited T. Löytynoja, I. Harczuk, K. Jänkälä, O. Vahtras, and H. Ågren The Journal of Chemical Physics 146, 124902 (2017); doi: 10.1063/1.4978941

https://rightsstatements.org/vocab/InC/1.0/
© 2017 The Authors. Published by AIP Publishing.
https://rightsstatements.org/vocab/InC/1.0/
doi:https://doi.org/10.1063/1.4978941
Näytä kaikki kuvailutiedot
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe201706127119
Tiivistelmä

Abstract

In this work, we apply quantum mechanics/molecular mechanics (QM/MM) approach to predict core-electron binding energies and chemical shifts of polymers, obtainable via X-ray photoelectron spectroscopy (XPS), using polymethyl methacrylate as a demonstration example. The results indicate that standard parametrizations of the quantum part (basis sets, level of correlation) and the molecular mechanics parts (decomposed charges, polarizabilities, and capping technique) are sufficient for the QM/MM model to be predictive for XPS of polymers. It is found that the polymer environment produces contributions to the XPS binding energies that are close to monotonous with the number of monomer units, totally amounting to approximately an eV decrease in binding energies. In most of the cases, the order of the shifts is maintained, and even the relative size of the differential shifts is largely preserved. The coupling of the internal core-hole relaxation to the polymer environment is found to be weak in each case, amounting only to one or two tenths of an eV. The main polymeric effect is actually well estimated already at the frozen orbital level of theory, which in turn implies a substantial computational simplification. These conclusions are best represented by the cases where the ionized monomer and its immediate surrounding are treated quantum mechanically. If the QM region includes only a single monomer, a couple of anomalies are spotted, which are referred to the QM/MM interface itself and to the neglect of a possible charge transfer.

Kokoelmat
  • Avoin saatavuus [37775]
oulurepo@oulu.fiOulun yliopiston kirjastoOuluCRISLaturiMuuntaja
SaavutettavuusselosteTietosuojailmoitusYlläpidon kirjautuminen
 

Selaa kokoelmaa

NimekkeetTekijätJulkaisuajatAsiasanatUusimmatSivukartta

Omat tiedot

Kirjaudu sisäänRekisteröidy
oulurepo@oulu.fiOulun yliopiston kirjastoOuluCRISLaturiMuuntaja
SaavutettavuusselosteTietosuojailmoitusYlläpidon kirjautuminen