title: The photophysical properties of expanded porphyrins: relationships between aromaticity, molecular geometry and non-linear optical properties.
abstract: Porphyrins, which consist of four pyrrolic subunits, are a ubiquitous class of naturally occurring compound with versatile photophysical properties. As an extension of the basic structure of the porphyrin macrocycle, there have been a multitude of approaches to synthesize expanded porphyrins with more than four pyrrole rings, leading to the modification of the macrocyclic ring size, planarity, number of pi-electrons and aromaticity. However, the relationship between the photophysical properties and the structures of expanded porphyrins has not been systematically investigated. The main purpose of this article is to describe the structure-property relationships of a variety of expanded porphyrins based on experimental and theoretical results, which include steady-state and time-resolved spectroscopic characterizations, non-linear absorption ability and nucleus-independent chemical shift calculations.
authors.affiliation: Department of Chemistry, Yonsei University, Seodaemoon gu, Shinchon dong 134, Seoul, 120-749, Korea.
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Lim
authors.forename: Zin Seok
authors.initials: ZS
authors.lastname: Yoon
authors.forename: Jae-Yoon
authors.initials: JY
authors.lastname: Shin
authors.forename: Kil Suk
authors.initials: KS
authors.lastname: Kim
authors.forename: Min-Chul
authors.initials: MC
authors.lastname: Yoon
authors.forename: Dongho
authors.initials: D
authors.lastname: Kim