A quantitative analysis of excitonic superhyperchromism in porphyrin J-/H-aggregates

Date

2004-06-21

Author

Yildirim, H
Iseri, EI
Gulen, D

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

37
views

0
downloads

We argue that the mixing between energetically well-separated bands should have a magnified importance in the aggregates exhibiting an excitonic structure with a collective superstate, for which the J-/H-aggregates of porphyrins represent excellent examples. We present a quantitative account of the excitonic intensity borrowing in such systems and reveal a remarkably simple explanation of its enhancement: superhyperchromism is manifested by the mediation of the interband (Q-B) coupling between the two superstates (in Q and B) of such aggregates. The significance of the superhyperchromism is conveyed through its effects on the absorption spectrum of a natural 'porphyrin J-aggregate' - the chlorosome.

Subject Keywords

Physical and Theoretical Chemistry, General Physics and Astronomy

URI

https://hdl.handle.net/11511/66629

Journal

CHEMICAL PHYSICS LETTERS

DOI

https://doi.org/10.1016/j.cplett.2004.05.009

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

Investigation of structure-spectroscopy-function relationship of two-dimensional J-aggregates of tetrachlorobenzimidazolocarbocyanine preferentially oriented in poly-vinyl-alcohol thin films Gulen, Demet; Atasoylu, Onur; ÖZÇELİK, Serdar (Elsevier BV, 2009-01-07) The structure-spectroscopy-function relationship of 1,1',1,3,3'-tetraethyl-5,5',6,6'-tetrachlorobenzimidazolocarbocyanine (TTBC) aggregates is studied using a combination of experimental and theoretical techniques. The aggregates are macroscopically aligned in poly-vinyl-alcohol thin films by vertical spin coating. Angular dependence of the UV-Vis spectra is measured at eleven different orientations between the electric field polarization and the macroscopic alignment axis. The aggregates are characterized ...
A theoretical study on the simplest fullerene, C-20 - an AM1 treatment Türker, Burhan Lemi (Elsevier BV, 2003-05-05) Within the constraints of AM1 (UHF) type semiempirical quantum chemical treatment, C-20 and its cationic and anionic forms were considered for their stabilities. The results revealed that C-20 has a greater tendency to act as electron acceptor than a donor. C-20(-) and C-20(-2) were found to be even more stable than C-20.
The valence electronic structure and conformational flexibility of epichlorohydrin Stranges, S.; Alagia, M.; Decleva, P.; Stener, M.; Fronzoni, G.; Toffolı, Danıele; Speranza, M.; Catone, D.; Turchini, S.; Prosperi, T.; Zema, N.; Contini, G.; Keheyan, Y. (Royal Society of Chemistry (RSC), 2011-01-01) The electronic structure of epichlorohydrin is investigated in the whole valence region by a combined experimental and theoretical study. The issue of controversial assignments of the molecular electronic structure is here addressed. Photoelectron spectra (PES) and Threshold Photoelectron spectra (TPES) of room temperature molecules in the gas phase are recorded. Geometries and energies of the stable conformers due to internal rotation of the C-C-C-Cl dihedral angle, gauche-II (g-II), gauche-I (g-I), and ci...
A comparative study of the dipole polarizability of some Zn clusters Papadopoulos, MG; Reis, H; Avramopoulos, A; Erkoc S, Erkoc S; Amirouche, L (American Chemical Society (ACS), 2005-10-13) We have employed a hierarchy of basis sets and computational techniques in order to approach the polarizability (alpha) of Zn-m, m = 2-20, in a systematic way. This procedure allows the proper approximate results to be selected and validated. More specifically, we have developed in a systematic way a series of basis sets that have been employed for the computation of the polarizability of the Zn atom. Comparison of the computed with the experimental and the best theoretical results allows us to comment on t...
A COMPARATIVE-STUDY OF VARIATIONAL TECHNIQUES FOR SCHRODINGER-EQUATIONS - POINTWISE QUALITY CRITERIA YURTSEVER, E (Walter de Gruyter GmbH, 1988-08-01) Different variational schemes for solving the Schrodinger equation are tested for the model potential of Kratzer-Fues. Wavefunctions are analyzed in terms of their global (expectation values) and local properties which are expressed as functions of coordinates. The Rayleigh-Ritz variation almost uniformly produces the most accurate expectation values. However the point properties show qualitatively different behaviour for different regions of the coordinate space. To define the local quality, a set of crite...

Citation Formats

H. Yildirim, E. Iseri, and D. Gulen, “A quantitative analysis of excitonic superhyperchromism in porphyrin J-/H-aggregates,” CHEMICAL PHYSICS LETTERS, pp. 302–307, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66629.