UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Benchmarking the Fundamental Electronic Properties of small TiO 2 Nanoclusters by GW and Coupled Cluster Theory Calculations

Berardo, E; Kaplan, F; Bhaskaran-Nair, K; Shelton, WA; van Setten, MJ; Kowalski, K; Zwijnenburg, MA; (2017) Benchmarking the Fundamental Electronic Properties of small TiO 2 Nanoclusters by GW and Coupled Cluster Theory Calculations. Journal of Chemical Theory and Computation , 13 (8) pp. 3814-3828. 10.1021/acs.jctc.7b00538. Green open access

[thumbnail of Zwijnenburg_acs.jctc.7b00538.pdf]
Preview
Text
Zwijnenburg_acs.jctc.7b00538.pdf - Published Version

Download (2MB) | Preview

Abstract

We study the vertical and adiabatic ionization potentials and electron affinities of bare and hydroxylated TiO2 nanoclusters, as well as their fundamental gap and exciton binding energy values, to understand how the clusters’ electronic properties change as a function of size and hydroxylation. In addition, we have employed a range of many-body methods; including G0W0, qsGW, EA/IP-EOM-CCSD, and DFT (B3LYP, PBE), to compare the performance and predictions of the different classes of methods. We demonstrate that, for bare clusters, all many-body methods predict the same trend with cluster size. The highest occupied and lowest unoccupied DFT orbitals follow the same trends as the electron affinity and ionization potentials predicted by the many-body methods, but are generally far too shallow and deep respectively in absolute terms. In contrast, the ΔDFT method is found to yield values in the correct energy window. However, its predictions depend upon the functional used and do not necessarily follow trends based on the many-body methods. Adiabatic potentials are predicted to be similar to their vertical counterparts and holes found to be trapped more strongly than excess electrons. The effect of hydroxylation on the clusters is to open up both the optical and fundamental gap. Finally, a simple microscopic explanation for the observed trends with cluster size and upon hydroxylation is proposed in terms of the onsite electrostatic potential.

Type: Article
Title: Benchmarking the Fundamental Electronic Properties of small TiO 2 Nanoclusters by GW and Coupled Cluster Theory Calculations
Open access status: An open access version is available from UCL Discovery
DOI: 10.1021/acs.jctc.7b00538
Publisher version: http://doi.org/10.1021/acs.jctc.7b00538
Language: English
Additional information: © 2017 American Chemical Society. This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Chemistry
URI: https://discovery.ucl.ac.uk/id/eprint/1566764
Downloads since deposit
116Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item