Charge separation in the excited state electron donor—acceptor compounds containing the piperazine moiety

✍ Scribed by A.M. Brouwer; R.D. Mout; P.H.Maassen van den Brink; H.J. van Ramesdonk; J.W. Verhoeven; J.M. Warman; S.A. Jonker

• Book ID: 103029979
• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 581 KB
• Volume: 180
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(91)85009-l

✦ Synopsis

Three bridged electron donor-acceptor systems are investigated containing a Ccyano-I-ethenylnaphthalene electron-acceptor andpiperidine (compound l), phenylpiperazine (2) and 4-methoxyphenylpiperazine (3) electron-donating groups. In the intramolecular charge-transfer states of 1 and 2, the extent of charge separation is similar, but in compound 3 the positive charge is shifted towards the more powerful arylamine donor site, which results in a significantly greater dipole moment. Optical absorption spectra of model radical cations demonstrate that the predominant charge localization on the trialkyl nitrogen in 2 and on the aryl nitrogen in 3 are a consequence of the b&able nature of the piperazine donors.