The effects of conformation and coordination to zinc(II) ions on the lowest triplet state of 6,6′-dimethyl-2,2′-bipyridine: A time-resolved ESR study

✍ Scribed by Mikio Yagi; Hayato Shirai; Jun Ohta; Jiro Higuchi

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 328 KB
• Volume: 160
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(89)87545-1

✦ Synopsis

Time-resolved ESR spectra have been observed for the lowest triplet states of s-transd,b'dimethyl-2,2'-bipyridine (s-transdmbpy), metal-free s-cis-dmbpy and [Zn(dmbpy) I'+ in rigid solutions at 77 K. The results indicate that, following the conformational change of dmbpy, the sublevel initially populated by intersystem crossing (ISC) changes from T, in s-transdmbpy to Ty in s-cisdmbpy, while it is mainly TX in [Zn (dmbpy) 1" (the y and z axes are close to the long and short in-plane molecular axes, respectively, and x is perpendicular to the molecular plane). The observed anisotropy in the ISC of [Zn(dmbpy) 12+ is anomalous for a planar %tn* aromatic molecule