Intrapolymer charge separation induced by picosecond multiphoton excitation: Synthetic polypeptides with a pendant 1-pyrenyl group in N,N-dimethylformamide

Hiroshi Masuhara*, Jun A. Tanaka, Noboru Mataga, Masahiko Sisido, Syun Egusa, Yukio Imanishi

*Corresponding author for this work

Research output: Contribution to journalArticle

5 Scopus citations

Abstract

Picosiscond transient absorption spectral measurements of polyalanines having a 1-pyrenyl chromophore were performed in N,N-dimethylformamide at room temperature. Absorption spectra at early stages were a superposition of the bands of the triplet, cationic, and anionic states of pyrenyl chromophores, indicating a new process of intrapolymer charge separation. On the other hand, the spectral change measured by reducing the excitation intensity was interpreted in terms of a monomer-excimer equilibrium. From an examination of excitation intensity, it was concluded that the ionic states are formed via a two-photon process and the triplet state via a three-photon process. Since the present behavior is common to a helical poly(L-alanine) and poly(DL-alanine), a local specific structure is responsible for the present process. Geometrical requirements of electron transfer between identical chromophores were discussed in detail.

Original languageEnglish
Pages (from-to)2791-2796
Number of pages6
JournalJournal of physical chemistry
Volume90
Issue number12
DOIs
StatePublished - 1 Jan 1986

Fingerprint Dive into the research topics of 'Intrapolymer charge separation induced by picosecond multiphoton excitation: Synthetic polypeptides with a pendant 1-pyrenyl group in N,N-dimethylformamide'. Together they form a unique fingerprint.

  • Cite this