Controllable and Reversible Inversion of the Electronic Structure in Nickel <i>N</i>-Confused Porphyrin: A Case When MCD Matters

Sripothongnak, Saovalak; Ziegler, Christopher J.; Dahlby, Michael R.; Nemykin, Victor N.

doi:10.1021/ic102255k

Cited by 32 publications

(38 citation statements)

References 63 publications

(25 reference statements)

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“…[14] Under our experimental conditions, the UV/Vis spectrum of the product formed after the first reduction of 4 in the thin-layer cell is characterized by a Soret band at 457 and four visible bands at 549, 591, 641 and 691 nm ( Figure 4, top right). This spectrum compares well with the published spectrum of deprotonated N-confused free-base tetraphenylporphyrin [14,36]…”

Section: Reductionsupporting

confidence: 84%

“…The one-electron oxidations and following chemical reactions are represented as E1 or E2 and C1 or C2, respectively, in Equations (1) and (2). 4 NcpH 4 ] 2 + as electrooxidation products is given in part by comparison with published spectral data for N-confused porphyrins in their protonated form, [14,36,37] in part by cyclic voltammograms taken in PhCN solutions with and without added trifluoroacetic acid (TFA; Figure 7) and in part by comparisons of the UV/Vis spectra obtained by spectroelectrochemical monitoring of the oxidations and that obtained after protonationof the neutral porphyrins 1-4 as shown by Equations (3) Figure 7 illustrates cyclic voltammograms for the oxidation of compound 4 in PhCN before and after addition acid to solution. In the absence of acid, two oxidations are observed.…”

Section: Oxidationmentioning

confidence: 99%

“…Cyclic voltammograms showing the first oxidation and first reduction as well as the HOMO-LUMO gap of a) N-confused free-base tetraarylporphyrins and b) free-base triarylcorroles in their mono-deprotonated, neutral and mono-protonated forms in PhCN containing 0.1 m TBAP. Data for the corroles was taken from reference [36]. and kept over the solution during each electrochemical and spectroelectrochemical experiment.…”

Section: Experimental Section Instrumentationmentioning

confidence: 99%

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Effect of Solvent and Protonation/Deprotonation on Electrochemistry, Spectroelectrochemistry and Electron‐Transfer Mechanisms of N‐Confused Tetraarylporphyrins in Nonaqueous Media

Xue

et al. 2014

Chemistry A European J

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A series of N-confused free-base meso-substituted tetraarylporphyrins was investigated by electrochemistry and spectroelectrochemistry in nonaqueous media containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) and added acid or base. The investigated compounds are represented as (XPh)4 NcpH2 , in which "Ncp" is the N-confused porphyrin macrocycle and X is a OCH3 , CH3 , H, or Cl substituent on the para position of each meso-phenyl ring of the macrocycle. Two distinct types of UV/Vis spectra are initially observed depending upon solvent, one corresponding to an inner-2H form and the other to an inner-3H form of the porphyrin. Both forms have an inverted pyrrole with a carbon inside the cavity and a nitrogen on the periphery of the π-system. Each porphyrin undergoes multiple irreversible reductions and oxidations. The first one-electron addition and first one-electron abstraction are located on the porphyrin π-ring system to give π-anion and π-cation radicals with a potential separation of 1.52 to 1.65 V between the two processes, but both electrogenerated products are unstable and undergo a rapid chemical reaction to give new electroactive species, which were characterized in the present study. The effect of the solvent and protonation/deprotonation reactions on the UV/Vis spectra, redox potentials and reduction/oxidation mechanisms is discussed with comparisons made to data and mechanisms for the structurally related free-base corroles and porphyrins.

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Section: Reductionsupporting

confidence: 84%

Section: Oxidationmentioning

confidence: 99%

Section: Experimental Section Instrumentationmentioning

confidence: 99%

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Effect of Solvent and Protonation/Deprotonation on Electrochemistry, Spectroelectrochemistry and Electron‐Transfer Mechanisms of N‐Confused Tetraarylporphyrins in Nonaqueous Media

Xue

et al. 2014

Chemistry A European J

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“…If you look at a molecule such as ZnTBTrAP, there is clearly a separation in the energy of the LUMO and the LUMO + 1 state, this can be attributed to the asymmetry and position of the nitrogens, which has already been reported. 64 The numerous orbital configurations that were calculated are not all included here, since the focus of this research encompasses 8 molecules in total. Another energy level to point out is the energy level of the LUMO and LUMO + 1 for ZnTBcisDAP, these two energies are so close (right on top of each other) in energy, they are nearly degenerate.…”

Section: Molecular Orbital Levelsmentioning

confidence: 99%

Ground and excited states of zinc phthalocyanine, zinc tetrabenzoporphyrin, and azaporphyrin analogs using DFT and TDDFT with Franck-Condon analysis

Theisen

Huang

Fleetham

et al. 2015

The Journal of Chemical Physics

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Articles you may be interested inGround and excited states of zinc phthalocyanine, zinc tetrabenzoporphyrin, and azaporphyrin analogs using DFT and TDDFT with Franck-Condon analysis The electronic structure of eight zinc-centered porphyrin macrocyclic molecules are investigated using density functional theory for ground-state properties, time-dependent density functional theory (TDDFT) for excited states, and Franck-Condon (FC) analysis for further characterization of the UV-vis spectrum. Symmetry breaking was utilized to find the lowest energy of the excited states for many states in the spectra. To confirm the theoretical modeling, the spectroscopic result from zinc phthalocyanine (ZnPc) is used to compare to the TDDFT and FC result. After confirmation of the modeling, five more planar molecules are investigated: zinc tetrabenzoporphyrin (ZnTBP), zinc tetrabenzomonoazaporphyrin (ZnTBMAP), zinc tetrabenzocisdiazaporphyrin (ZnTBcisDAP), zinc tetrabenzotransdiazaporphyrin (ZnTBtransDAP), and zinc tetrabenzotriazaporphyrin (ZnTBTrAP). The two latter molecules are then compared to their phenylated sister molecules: zinc monophenyltetrabenzotriazaporphyrin (ZnMPTBTrAP) and zinc diphenyltetrabenzotransdiazaporphyrin (ZnDPTBtransDAP). The spectroscopic results from the synthesis of ZnMPTBTrAP and ZnDPTBtransDAP are then compared to their theoretical models and nonphenylated pairs. While the Franck-Condon results were not as illuminating for every B-band, the Q-band results were successful in all eight molecules, with a considerable amount of spectral analysis in the range of interest between 300 and 750 nm. The π-π * transitions are evident in the results for all of the Q bands, while satellite vibrations are also visible in the spectra. In particular, this investigation finds that, while ZnPc has a D 4h symmetry at ground state, a C 4v symmetry is predicted in the excited-state Q band region. The theoretical results for ZnPc found an excitation energy at the Q-band 0-0 transition of 1.88 eV in vacuum, which is in remarkable agreement with published gas-phase spectroscopy, as well as our own results of ZnPc in solution with Tetrahydrofuran that are provided in this paper. C 2015 AIP Publishing LLC. [http://dx

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“…TDDFT-PCM calculations were conducted with BP86 functional coupled with 6-311G(d) basis set [36] and dichloromethane as a solvent media. GGA BP86 exchange-correlation functional was used in TDDFT-PCM calculations because, as it was shown before, it provides a better accuracy for energies of -* transitions in porphyrinoids compared to more popular hybrid B3LYP exchangecorrelation functional [37][38][39]. The first 50 excited states were calculated using equilibrium and non-equilibrium PCM solvation methods.…”

Section: Methodsmentioning

confidence: 99%

Comparative electronic structures and UV–vis spectra of tribenzosubporphyrin, tribenzomonoazasubporphyrin, tribenzodiazasubporphyrin, and subphthalocyanine: Insight from DFT and TDDFT calculations

Gao¹,

Solntsev²,

Nemykin³

2012

Journal of Molecular Graphics and Modelling

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Controllable and Reversible Inversion of the Electronic Structure in Nickel N-Confused Porphyrin: A Case When MCD Matters

Cited by 32 publications

References 63 publications

Effect of Solvent and Protonation/Deprotonation on Electrochemistry, Spectroelectrochemistry and Electron‐Transfer Mechanisms of N‐Confused Tetraarylporphyrins in Nonaqueous Media

Effect of Solvent and Protonation/Deprotonation on Electrochemistry, Spectroelectrochemistry and Electron‐Transfer Mechanisms of N‐Confused Tetraarylporphyrins in Nonaqueous Media

Ground and excited states of zinc phthalocyanine, zinc tetrabenzoporphyrin, and azaporphyrin analogs using DFT and TDDFT with Franck-Condon analysis

Comparative electronic structures and UV–vis spectra of tribenzosubporphyrin, tribenzomonoazasubporphyrin, tribenzodiazasubporphyrin, and subphthalocyanine: Insight from DFT and TDDFT calculations

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