CIDEP from a polarized ketone triplet state incarcerated within a nanocapsule to a nitroxide in the bulk aqueous solution

Steffen Jockusch, Mintu Porel, Vaidhyanathan Ramamurthy, Nicholas J. Turro

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Thioxanthone and benzil derivatives were incarcerated into an octa acid nanocapsule. Photoexcitation of these ketones generated electronic triplet excited states, which become efficiently quenched by positively charged nitroxides adsorbed outside on the external surface of the negatively charged nanocapsule. Although the triplet excited ketone and quencher are separated by a molecular wall (nanocapsule), quenching occurs on the nanosecond time scale and generates spin-polarized nitroxides, which were observed by time-resolved EPR spectroscopy. Because opposite signs of spin polarization of nitroxides were observed for thioxanthone and benzil derivatives, it is proposed that the electron spin polarization transfer mechanism of spin-polarized triplet states to nitroxides is the major mechanism of generating nitroxide polarization.

Original languageEnglish
Pages (from-to)2877-2880
Number of pages4
JournalJournal of Physical Chemistry Letters
Volume2
Issue number22
DOIs
StatePublished - Nov 17 2011

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Nanocapsules
Ketones
ketones
atomic energy levels
Spin polarization
aqueous solutions
polarization
Derivatives
Photoexcitation
photoexcitation
Excited states
electron spin
Paramagnetic resonance
Quenching
quenching
Spectroscopy
Polarization
acids
Acids
Electrons

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

CIDEP from a polarized ketone triplet state incarcerated within a nanocapsule to a nitroxide in the bulk aqueous solution. / Jockusch, Steffen; Porel, Mintu; Ramamurthy, Vaidhyanathan; Turro, Nicholas J.

In: Journal of Physical Chemistry Letters, Vol. 2, No. 22, 17.11.2011, p. 2877-2880.

Research output: Contribution to journalArticle

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