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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Magnetic circular dichroism spectroscopy of cobalt tetraphenyltetraacenaphthoporphyrin
John Mack1, Yoshiaki Asano, Nagao Kobayashi
1Department of Chemistry, University of Western Ontario, London, Ontario, Canada N6A 5B7.
Abstract:
The first MCD spectral data for an open shell first row transition metal complex of tetraphenyltetraacenaphthoporphyrin (TPTANP) are reported. The B (or Soret) band of cobalt tetraphenyltetraacenaphthoporphyrin (Co(II)TPTANP(-2)) exhibits an anomalous negative Faraday A(1) term as was reported previously in the case of ZnTPTANP, while a positive A(1) term is observed for the Q band. INDO/1 geometry optimizations predict that the TPTANP ligand is saddled due to steric hindrance at the ligand periphery to a slightly lesser extent than is the case with ZnTPTANP. The Q and B bands of CoTPTANP arising from the pi-system are blue shifted relative to those of ZnTPTANP, based on the "hypso" effect reported previously for planar porphyrin complexes of d(6-9) transition metals.
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