Tetrabenzoporphyrins: Metal Incorporation and Exchange Kinetics,
                        Ligational Equilibria and Pulse Radiolysis Studies

Cromer, S.; Hambright, Peter; Grodkowski, J.; Neta, P.

doi:10.1002/(sici)1099-1409(199701)1:1<45::aid-jpp3>3.0.co;2-d

Cited by 9 publications

(3 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many studies have examined the optical properties of free-base and metal-substituted porphyrin-based macromolecules, typically suspended in solution or in a gaseous phase. 22,32,[35][36][37][38][39] Typical absorption spectra of porphyrin molecules include a Soret, or B, band ͑a strong optical absorption band in the near-UV range in a heme or heme-like mol-ecule͒ around h = 3 eV and Q bands ͑weaker optical absorption bands in the visible range͒ between 1.75Ͻ h ͑eV͒ Ͻ2.75, 37 with variations in peak position and peak splitting due to metal incorporation and the peripheral substituents ͑here, Ni and benzene, respectively͒. The solid NiTBP and NiCP films presented here display these typical optical properties; absorbance spectra for drop-and spuncast NiTBP and spun-cast NiCP are displayed in 40 Also of note in Fig.…”

Section: Optical Absorbance and Atomic Force Microscopymentioning

confidence: 99%

Solution-processed nickel tetrabenzoporphyrin thin-film transistors

Shea

Kanicki

Pattison

et al. 2006

Journal of Applied Physics

View full text Add to dashboard Cite

We describe nickel tetrabenzoporphyrin ͑NiTBP͒ as a solution-processible organic semiconductor. Whereas porphyrins in an unmodified state are typically planar and insoluble, a precursor synthetic route ͑NiCP͒ was used to deposit thin films via solution. Amorphous, insulating thin films of NiCP were deposited, and thermally converted to polycrystalline, semiconducting NiTBP. Films were studied using optical absorption and microscopy, atomic force microscopy, and x-ray diffraction. Highly concentrated NiCP was shown to form large, needle-shaped crystals drop-cast from solution. NiTBP thin-film field-effect transistors fabricated from spun-cast films demonstrated charge-carrier field-effect mobilities on the order of 0.1 and 0.2 cm 2 / V s and accumulation threshold voltages of −19 and −13, in the linear and saturation regimes, respectively.

show abstract

Section: Optical Absorbance and Atomic Force Microscopymentioning

confidence: 99%

Solution-processed nickel tetrabenzoporphyrin thin-film transistors

Shea

Kanicki

Pattison

et al. 2006

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…Though now readily synthesizable, NiTBP, whose electronic spectrum is being investigated in the present work, is only slightly soluble in most noncoordinating organic solvents. It dissolves appreciably in chloroform or dichloromethane after addition of a few percent of pyridine, but optical spectra taken in these mixtures are not suitable for comparison with theoretical data, since, as recently demonstrated, 69 NiTBP axially binds two pyridine ligands. The axial coordination of the metal modifies substantially the ground-state electronic structure, and significant spectral changes are observed in the Soret band region.…”

Section: Excited States and Optical Spectramentioning

confidence: 99%

The Optical Spectra of NiP, NiPz, NiTBP, and NiPc: Electronic Effects ofMeso-tetraaza Substitution and Tetrabenzo Annulation

Rosa¹,

Ricciardi²,

Baerends³

et al. 2001

J. Phys. Chem. A

129

128

View full text Add to dashboard Cite

Time-dependent density functional calculations have been performed on the symmetry and spin-allowed E u excited states of the nickel tetrapyrrole series, NiP, NiPz, NiTBP, and NiPc. Optical spectra collected in noncoordinating solvents are presented for NiTBP, for the newly synthesized octaethyl nickel porphyrazine, NiOEPz, and for MgOEPz. The theoretical results prove to agree very well with the experimental data, providing an accurate description of the UV-vis spectra. The effects on the optical spectra of introducing in the basic porphyrinic ring, aza bridges, benzo rings, both aza bridges and benzo rings, and a transition metal are highlighted and interpreted on the basis of the electronic structure changes occurring along the series. The following results were found: (i) The near-degeneracy of the configurations (a 1u e g ) and (a 2u e g ) of the fourorbital model leads to strong mixing in NiP. The resulting low-energy state corresponds to the Q band with low intensity due to opposing transition dipoles of the contributing transitions. In NiTBP, NiPz, and NiPc, the degeneracy is lifted, and the lowest transition becomes increasingly purely (a 1u e g ) with concomitant larger intensities in the Q band, which is most intense in NiPc. (ii) The B band is calculated to correspond in NiP to a strong mixture of the degenerate (a 1u e g ) and (a 2u e g ) configurations with parallel transition dipoles, hence a large intensity. In NiPz and NiPc, the B band can no longer be described in terms of the four-orbital model, it has considerable MLCT character in NiPz and corresponds to a more complicated configuration mixing in NiPc. (iii) Transitions involving metal 3d states, either MLCT or LMCT, influence notably the spectrum to the blue of the B band.

show abstract

“…There have been reports on how trans metalation depends on the porphyrin structure in the initial MP [6][7][8][9], on the nature of the metal ion being replaced [10,11], on the nature of the metal ion being introduced [6,12], and on the nature of the salt anion [9,13]. Likely mechanisms have been suggested for metal ion exchange in labile MPs [6,9,14] same time, the solvent effect as a significant factor in the reaction rate and mechanism [15] has not been properly investigated at the quantitative level.…”

mentioning

confidence: 99%

Kinetic control of the transmetalation of labile metalloporphyrins in individual and mixed solvents

Berezin

Shukhto

Lazareva

2012

Russ. J. Inorg. Chem.

View full text Add to dashboard Cite

Transmetalation reactions of cadmium complexes of tetraphenylporphine (CdTPP, I) and tetra benzoporphine (CdTBP, II) in individual and mixed solvents have been investigated. For individual solvents, provided that the reaction proceeds via the same mechanism, its rate generally increases as the donor number increases in the order DMSO < DMF < PrOH 1 < MeCN (CdTPP-Zn(OAc) 2 -Solv system). On passing to the CdTPP-Cu(OAc) 2 -Solv system, the reaction rate order changes to DMSO < PrOH 1 < MeCN < DMF because the transmetalation mechanism changes from mixed to associative, as follows from the reaction order with respect to the salt being zero. The effect of the DMSO-DMF mixed solvent on the transmetalation reac tion is limited to changing the reaction rate through alteration of the stability of the [CuX 2 (Solv 1 ) n -m -2 (Solv 2 ) m ] solvated salts. The trans effect of the ligands in the solvated salts does not increase the transmetala tion rate.

show abstract

Tetrabenzoporphyrins: Metal Incorporation and Exchange Kinetics, Ligational Equilibria and Pulse Radiolysis Studies

Cited by 9 publications

References 56 publications

Solution-processed nickel tetrabenzoporphyrin thin-film transistors

Solution-processed nickel tetrabenzoporphyrin thin-film transistors

The Optical Spectra of NiP, NiPz, NiTBP, and NiPc: Electronic Effects ofMeso-tetraaza Substitution and Tetrabenzo Annulation

Kinetic control of the transmetalation of labile metalloporphyrins in individual and mixed solvents

Contact Info

Product

Resources

About