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?-Conjugation of two nitronyl nitroxides-attached diarylethenes.

ABSTRACT: Unusual blue shift of the absorption maxima of two nitronyl nitroxide attached diarylethene through phenyl units (DAE-phe-NN) with increasing number of phenyl units is examined by time dependent density functional theory (TDDFT). The extended ?-conjugation between nitronyl nitroxide and diarylethene is rather suppressed by the bridge phenyl units. In comparison, the red shift found in two nitronyl nitroxide attached diarylethenes through thiophene units (DAE-thio-NN) with increasing number of thiophene units is due to the longer ?-conjugation induced by smaller dihedral angles between diarylethene and bridge and between bridges.

SUBMITTER: Yokojima S

PROVIDER: S-EPMC3089375 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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π-Conjugation of two nitronyl nitroxides-attached diarylethenes.

Yokojima Satoshi S Kobayashi Takao T Shinoda Keiko K Matsuda Kenji K Higashiguchi Kenji K Nakamura Shinichiro S

The journal of physical chemistry. B 20110328 18

Unusual blue shift of the absorption maxima of two nitronyl nitroxide attached diarylethene through phenyl units (DAE-phe-NN) with increasing number of phenyl units is examined by time dependent density functional theory (TDDFT). The extended π-conjugation between nitronyl nitroxide and diarylethene is rather suppressed by the bridge phenyl units. In comparison, the red shift found in two nitronyl nitroxide attached diarylethenes through thiophene units (DAE-thio-NN) with increasing number of th ...[more]

PMID: 21443230

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