An X-ray absorption and photoemission study of the electronic structure of Ni porphyrins and Ni N-confused porphyrin
Citation:
S. A. Krasnikov, N. N. Sergeeva, M. M. Brzhezinskaya, A. B. Preobrajenski, Y. N. Sergeeva, N. A. Vinogradov, A. A. Cafolla, M. O. Senge, A. S. Vinogradov, An X-ray absorption and photoemission study of the electronic structure of Ni porphyrins and Ni N-confused porphyrin, Journal of Physics Condensed Matter, 20, 2008, 235207Download Item:
An X-ray.pdf (Published (author's copy) - Peer Reviewed) 287.1Kb
Abstract:
Investigations of chemical bonding and electronic structure features for
polycrystalline (porphyrinato)nickel (II) (NiP, the simplest Ni porphyrin),
(5,10,15,20-tetraphenylporphyrinato)nickel (II) (NiTPP) and
(2-aza-21-carba-5,10,15,20-tetraphenylporphyrinato)nickel (II) (N-confused NiTPP, NiNCTPP)
have been performed by means of high-resolution soft x-ray absorption and x-ray
photoemission spectroscopy. The Ni 2p3/2 x-ray absorption spectra show strong
?-back-bonding in these compounds leading to a high-energy shift (1.2 eV for the NiP and
NiTPP) of the entire absorption structure compared to Ni metal. It has been found that the main
absorption line of the Ni 2p3/2 spectrum of the NiNCTPP is shifted by an additional 0.5 eV to
higher energies in comparison with those for other nickel porphyrins. This shift is evidence of
stronger back-donation (metal-to-ligand charge transfer) and a smaller effective number of 3d
electrons on the central Ni atom in the NiNCTPP as compared to other Ni porphyrins. The
confused N atom in the NiNCTPP is of pyrrolic type (protonated nitrogen), which was
confirmed by the N 1s absorption and core-level photoemission spectra.
Sponsor
Grant Number
Science Foundation Ireland (SFI)
Author's Homepage:
http://people.tcd.ie/sengemDescription:
PUBLISHED
Author: SENGE, MATHIAS; SERGEEVA, NATALIA
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Journal ArticleCollections:
Series/Report no:
Journal of Physics - Condensed Matter20
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Chemistry, 3d transition metalSubject (TCD):
Nanoscience & MaterialsDOI:
http://dx.doi.org/10.1088/0953-8984/20/23/235207Licences: