Effect of metal and substituents on the quasi-line spectra of some metalloporphyrins

Aronowitz, Yvonne Jones; Gouterman, Martin

doi:10.1016/0022-2852(77)90266-1

Cited by 29 publications

(8 citation statements)

References 24 publications

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“…Since the lifetime of the lowest singlet (singdoublet) state of CuP is estimated to be shorter than 100 fs [13], it could not be detected in our measurements with 10 ps pulse duration. Therefore, we assume that the triplet ('rr, ~ * ) excited state is responsible for the short-lived TA spectrum.…”

Section: Resultsmentioning

confidence: 82%

Intermolecular interaction of photoexcited Cu(TMpy-P4) with water studied by transient resonance Raman and picosecond absorption spectroscopies

Kruglik

Ermolenkov

Shvedko

et al. 1997

Chemical Physics Letters

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A photoinduced complex between Cu(TMpy-P4) and water molecules, reversibly axially coordinated to the central metal, was observed in picosecond transient absorption and nanosecond resonance Raman experiments. This complex is rapidly created (z~ = 15 + 5 ps) in the excited triplet (~r, ~r * ) state of Cu-porphyrin, and the subsequent relaxation is proposed to proceed via two parallel pathways. One is fast and efficient (>/90% of molecules), and presumably involves a (ax, d) charge-transfer state. The second pathway is slow (z 2 >> 1 ns), has a low quantum yield (~< 10%) and involves the excited (d, d) state which is responsible for transient Raman features at = 1553 cm -I (u2*) and = 1347 cm -1 (u4*), and for low-intensity long-lived transient absorption features.

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Section: Resultsmentioning

confidence: 82%

Intermolecular interaction of photoexcited Cu(TMpy-P4) with water studied by transient resonance Raman and picosecond absorption spectroscopies

Kruglik

Ermolenkov

Shvedko

et al. 1997

Chemical Physics Letters

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“…As can be seen in Fig. 5A, the XRD diagram of nanofibers formed from conjugate 1 in n-hexane shows a comparatively strong and narrow peak at 2q ¼ 2.26 (corresponding to 3.91 nm) along with ten higher order diffraction peaks corresponding to 3.91/n nm where n ¼ 2, 3, 4, 6,7,8,9,11,13 and 14 due to the refractions from the (100) plane and its higher refractions, indicating the existence of a very regular repetition in this direction, Fig. 5.…”

Section: X-ray Diffraction Patterns Of the Aggregatesmentioning

confidence: 90%

Morphology and chirality controlled self-assembled nanostructures of porphyrin–pentapeptide conjugate: effect of the peptide secondary conformation

Wang

Chen

et al. 2011

J. Mater. Chem.

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An optically active porphyrin-pentapeptide conjugate 1, actually a porphyrinato zinc complex covalently linked with a glycinyl-alanyl-glycinyl-alanyl-glycine (GAGAG) peptide chain, was designed and synthesized. The self-assembly properties of this novel porphyrin-pentapeptide conjugate in THF/nhexane and THF/water were comparatively investigated by electronic absorption, circular dichroism (CD), IR spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) technique. Associated with the different secondary conformation of the pentapeptide chain covalently linked to the porphyrin ring in different solvent systems, self-assembly of conjugate 1 leads to the formation of nanofibers with right-handed helical arrangement and nanotubes with left-handed helical arrangement in a stack of porphyrin chromophores according to the CD spectroscopic result in apolar THF/n-hexane (1 : 3) and polar THF/water (1 : 3) system depending on the cooperation between intramolecular or intermolecular hydrogen bonding interaction with chiral discrimination between pentapeptide chains and porphyrin-porphyrin interactions in the direction parallel to the tetrapyrrole ring of neighboring conjugate molecules. IR spectroscopic result clearly reveals the a-helix and b-sheet secondary conformation, respectively, employed by the pentapeptide chain attached at the porphyrin core in the nanostructures formed in THF/n-hexane (1 : 3) and THF/ water (1 : 3). The X-ray diffraction (XRD) result confirms that in the nanotubes, a dimeric supramolecular bilayer structure was formed through an intermolecular hydrogen bonding interaction between two conjugate molecules which, as the building block, self-assembles into the target nanostructures. These results clearly reveal the effect of a secondary conformation of pentapeptide chain in the conjugate molecule on the packing mode of porphyrin chromophore, supramolecular chirality, and morphology of the self-assembled nanostructure. The present result represents not only the first example of organic nanostructures self-assembled from a covalently linked porphyrin-pentapeptide conjugate, but more importantly the first effort towards controlling and tuning the morphology and in particular the supramolecular chirality of porphyrin nanostructures via tuning the secondary conformation of peptides in different solvent systems, which is helpful towards understanding, designing, preparing, and mimicking the structure and role of naturally occurring porphyrin-peptide conjugates. In addition, both nanofibers and nanotubes were revealed to show good semiconducting properties.

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“…S4 and the data are compiled in Table S1. In line with the 5,10,15,20-tetraphenyl-porphyrinato zinc compound ZnTPP [5], G 2 ZnPor showed typical feature of porphyrinato zinc compounds in electronic absorption spectra in Fig. S4 (black line).…”

mentioning

confidence: 84%

Morphology controlled nano-structures of a porphyrin dendrimer complex: Solvent effect on the self-assembly behavior

Song

Jia

et al. 2015

Inorganic Chemistry Communications

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Effect of metal and substituents on the quasi-line spectra of some metalloporphyrins

Cited by 29 publications

References 24 publications

Intermolecular interaction of photoexcited Cu(TMpy-P4) with water studied by transient resonance Raman and picosecond absorption spectroscopies

Intermolecular interaction of photoexcited Cu(TMpy-P4) with water studied by transient resonance Raman and picosecond absorption spectroscopies

Morphology and chirality controlled self-assembled nanostructures of porphyrin–pentapeptide conjugate: effect of the peptide secondary conformation

Morphology controlled nano-structures of a porphyrin dendrimer complex: Solvent effect on the self-assembly behavior

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