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  • Crystal structure, stability, spectroscopy, electronic structure, and ultrafast excited-state dynamics of the elusive iron(II) phthalocyanine axially coordinated with DABCO ligands
Title: Crystal structure, stability, spectroscopy, electronic structure, and ultrafast excited-state dynamics of the elusive iron(II) phthalocyanine axially coordinated with DABCO ligands
The elusive PcFe(DABCO)2(Pc = phthalocyaninato(2-) ligand; DABCO = 1,4-diazabicyclo[2.2.2]octane) complex was prepared and characterized by UV-Vis, MCD,1H NMR, and Mössbauer spectroscopies. The X-ray crystal structure of this complex indicates the longest Fe-N(DABCO) bond distance among all known PcFeL2complexes with nitrogen donors as the axial ligands. The target compound is only stable in the presence of large access of the axial ligand and rapidly converts into the (PcFe)2O [Formula: see text]-oxo dimer even at a modest temperature. The electronic structure of the PcFe(DABCO)2complex was elucidated by DFT and TDDFT methods. The DFT calculations predicted a very small singlet-triplet gap in this compound. The femtosecond transient absorption spectroscopy is indicative of extremely fast ([Formula: see text]200 fs) deactivation of the first excited state in PcFe(DABCO)2with a lack of formation of the long-lived low-energy triplet state.  more » « less
Award ID(s):
2153081
PAR ID:
10512032
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
World Scientific
Date Published:
Journal Name:
Journal of Porphyrins and Phthalocyanines
Volume:
27
Issue:
07n10
ISSN:
1088-4246
Page Range / eLocation ID:
1131 to 1141
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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