Near-Unity Quantum Yields for Intersystem Crossing and Singlet Oxygen Generation in Polymethine-like Molecules: Design and Experimental Realization

Abstract

The photophysical properties of two pairs of squaraine molecules where two oxygen atoms in a squaraine bridge are replaced with sulfur atoms are investigated. This substitution leads to an inversion of the lowest singlet pi-pi* electronic transition by an n-pi* transition, effectively reducing the energy difference between singlet and triplet states and significantly increasing the intersystem crossing efficiency without the use of "heavy atoms". Experimental results, in agreement with quantum chemical calculations, show near-unity values for triplet quantum yield and singlet oxygen generation quantum yield for sulfur-containing squaraines, which are potentially useful for two-photon photodynamic therapy.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2010
Accession Number
ADA596383

Entities

People

  • Alexey D. Kachkovski
  • Alexey I. Tolmachev
  • Andriy O. Gerasov
  • Artëm E. Masunov
  • Davorin Peceli
  • Honghua Hu
  • Lazaro A Padilha
  • Olga V. Przhonska
  • Scott Webster
  • Yurii L. Slominsky

Organizations

  • University of Central Florida

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Absorption
  • Absorption Spectra
  • Alkenes
  • Chemistry
  • Energy
  • Fluorescence
  • Military Research
  • Molecular Structure
  • Optics
  • Organic Chemistry
  • Oxygen
  • Photons
  • Quantum Properties
  • Quantum Yields
  • Spectra
  • Spin-Orbit Interaction
  • Transitions

Fields of Study

  • Physics

Readers

  • Chemistry (specifically Chemical Fluorescence)
  • Combustion science or combustion engineering.

Technology Areas

  • Microelectronics
  • Quantum Computing