title: Evaluation of planarity and aromaticity in sapphyrin and inverted sapphyrin using a bidirectional NICS (Nucleus-Independent Chemical Shift) scan method?
abstract: Using the bidirectional NICS scan method in conjunction with two-photon absorption (TPA) measurements, it has proved possible to determine the relationship between pi-conjugation and aromaticity in two structurally related expanded porphyrin systems, sapphyrin and inverted sapphyrin, and establish that differences in these defining factors depend on the presence or absence of a key sp3 hybrid molecular orbital within the macrocyclic periphery.
authors.affiliation: Department of Chemistry, Yonsei University, Seoul 120-749, Korea.
authors.forename: Zin Seok
authors.initials: ZS
authors.lastname: Yoon
authors.forename: Su Bum
authors.initials: SB
authors.lastname: Noh
authors.forename: Dong-Gyu
authors.initials: DG
authors.lastname: Cho
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sessler
authors.forename: Dongho
authors.initials: D
authors.lastname: Kim
mesh_terms: D011166:Porphyrins / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D011166:Porphyrins; C440448:sapphyrin