Home > Research > Publications & Outputs > Development of Density Functional Methods for E...

Associated organisational unit

Electronic data

  • 2021PeterFletcherPhD

    Final published version, 4.51 MB, PDF document

    Available under license: CC BY-NC-ND: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License

Text available via DOI:

View graph of relations

Development of Density Functional Methods for Electronic Excited States and the Influence of Molecular Structure on Electronic Excited States

Research output: ThesisDoctoral Thesis

Publication date2021
Number of pages176
Awarding Institution
  • Lancaster University
<mark>Original language</mark>English


An extensive assessment of six density functional approximations has been
undertaken, each of these approximations have their own merits and faults.
Range separated hybrids are the best performing for excited state properties
of those approximations assessed.

There has been an attempt to generate an attenuated form of PBE
(CAM-PBE) which initially had issues which were investigated in detail
regarding the dependence of Hartree–Fock exchange energy on approximation performance. This attenuated form of PBE had similar performance to

The development of a set of benchmark data for excited state geometries
and emission energies was undertaken with a wide range of organic molecules
due to the lack of such benchmark data existing currently. This means
the accuracy of density functional approximations for calculation of such
properties is unknown so there is a clear need for this benchmark data to
be developed and used to assess the accuracy of these approximations.
The benchmark data for excited state geometries and emission energies
was used to assess the performance of a range of density functional approximations for these properties. This assessment has suggested that there are issues when applying current density functional approximations away from
the ground state where they have been tuned and optimised. This suggests
that there may be some merit in developing specialised density functional
approximations for the calculation of excited state properties.

The existing density functional approximations have been used to assist with experimental investigations of porous polymers and in explaining
the excited state properties of these polymers. This was done using model
systems and has enabled a deeper understanding of the experimental observations