Article
Version 1
Preserved in Portico This version is not peer-reviewed
On the Low-Lying Electronically Excited States of Azobenzene Dimers: Transition Density Matrix Analysis
Version 1
: Received: 18 June 2021 / Approved: 21 June 2021 / Online: 21 June 2021 (10:20:13 CEST)
A peer-reviewed article of this Preprint also exists.
Titov, E. On the Low-Lying Electronically Excited States of Azobenzene Dimers: Transition Density Matrix Analysis. Molecules 2021, 26, 4245. Titov, E. On the Low-Lying Electronically Excited States of Azobenzene Dimers: Transition Density Matrix Analysis. Molecules 2021, 26, 4245.
Abstract
Azobenzene-containing molecules may associate with each other in systems such as self-assembled monolayers or micelles. The interaction between azobenzene units leads to a formation of exciton states in these molecular assemblies. Apart from local excitations of monomers, the electronic transitions to the exciton states may involve charge transfer excitations. Here, we perform quantum chemical calculations and apply transition density matrix analysis to quantify local and charge transfer contributions to the lowest electronic transitions in azobenzene dimers of various arrangements. We find that the transitions to the lowest exciton states of the considered dimers are dominated by local excitations, but charge transfer contributions become sizable for some of the lowest ππ* electronic transitions in stacked and slip-stacked dimers at short intermolecular distances. In addition, we assess different ways to partition the transition density matrix between fragments. In particular, we find that the inclusion of the atomic orbital overlap has a pronounced effect on quantifying charge transfer contributions if a large basis set is used.
Keywords
azobenzene; transition density matrix; exciton; charge transfer; excited states; TD-DFT; ADC(2)
Subject
Chemistry and Materials Science, Theoretical Chemistry
Copyright: This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Comments (0)
We encourage comments and feedback from a broad range of readers. See criteria for comments and our Diversity statement.
Leave a public commentSend a private comment to the author(s)
* All users must log in before leaving a comment