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Updated: Mar 10, 2026

Synthesis of Wavelength-shifting DNA Hybridization Probes by Using Photostable Cyanine Dyes

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Published on: July 6, 2016

Color in Bridge-Substituted Cyanines.

¹School of Mathematics and Physics, The University of Queensland , Brisbane QLD 4072, Australia.

The Journal of Physical Chemistry. A

|December 16, 2016

Summary

This study explains cyanine dye resonance using a novel maximum-entropy valence-bond approach. It quantifies the limits of resonance, revealing superexchange from covalent bonding as key to optical properties.

Area of Science:

* Quantum chemistry
* Materials science
* Spectroscopy

Background:

* Cyanine dye color theories rely on

Purpose of the Study:

* To elucidate the emergence of resonance models from many-electron systems in cyanine dyes.
* To provide ab initio justification for empirical models of methine optical response.

Main Methods:

* Utilized a maximum-entropy approach with valence-bond representations.
* Employed state-averaged complete-active space self-consistent field (CASSCF) models.
* Calculated energies and couplings of high-energy valence-bond structures.

Main Results:

* Presented valence-bond Hamiltonians for bridge-substituted Michler's hydrol blue derivatives.

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[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

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Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach

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* Quantified a lower bound for the Brown-Okamoto σ_p⁺ parameter, beyond which resonance breaks down.

* Determined that superexchange from covalent bonding, not charge-carrier delocalization, dominates effective coupling.

Conclusions:

* The study offers ab initio validation for diabatic-state models of methine optical response.
* Provides fundamental insights into the optoelectronic properties of cyanine dyes.