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Electrical Conductance and Thermopower of β-Substituted Porphyrin Molecular Junctions─Synthesis and Transport
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Rapid Exciton Transport and Structural Defects in Individual Porphyrinic Metal Organic Framework Microcrystals
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Amethyrin-type expanded porphyrins that display anti-aromatic character upon protonation
The use of protonation to switch nonaromatic expanded porphyrinsto their corresponding anti-aromatic forms has not been widelyexplored. Here, we show that free-base pyriamethyrin and dipyr-iamethyrin display nonaromatic character, as inferred from NMRspectroscopic analyses, their optical properties, and theoreticalcalculations. Addition of two protons extends thep– conjugationof these amethyrin analogues and yields formally anti-aromaticsystems.
X-ray absorption spectroscopy of exemplary platinum porphyrin and corrole derivatives: metal- versus ligand-centered oxidation
Platinum L 3 -edge XAS and DFT calculations on three well-characterized Pt porphyrinoid complexes have provided detailed insights into metal- versus ligand-centered oxidation and ligand field effects.
Polariton ring currents and circular dichroism of Mg-porphyrin in a chiral cavity
Placing aromatic molecules in a chiral optical cavity can break time-reversal symmetry and generate polariton ring currents with a linearly polarized pump. Such currents can be probed by circular dichroism, with one order of magnitude enhancement.
Differences in chemoselectivity in olefin oxidation by a series of non-porphyrin manganese( iv )-oxo complexes
High valent metal-oxo intermediates are versatile oxidants known to facilitate both oxygen atom transfer (OAT) and hydrogen atom transfer (HAT) reactions in nature.
NiFe-mixed metal porphyrin aerogels as oxygen evolution reaction catalysts in alkaline electrolysers
Aerogels are a very interesting group of materials owing to their unique physical and chemical properties, which among others, make them efficient oxygen evolution reaction catalysts.
Highly Active Oxygen Reduction Electrocatalysts Derived from an Iron-Porphyrin Framework
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Interstellar matter. II - Diffuse interstellar lines and porphyrins.
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Spectrofluorometric search for porphyrins in Apollo 14 surface fines.
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Fluorometric search for porphyrins in Apollo 15 exhaust-contaminated surface fines and deep drill cores and Apollo 16 surface fines
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Returned lunar samples porphyrin analysis
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Petroporphyrins. I - Preliminary characterization of the porphyrins of gilsonite
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Porphyrins in the interstellar medium (in grains)
Spectral sensitivity of the chromophores to their immediate chemical environment establishes some of the chemical constituents of the grains in which they reside. These are: (1) Paraffins, such as, octane, nonane, decane, and others...(needed for Shpolskii matrices and producing quasilines); and (2) Pyridine. The presence of pyridine is required not only to produce the spectral DIB matching, but also to produce the 36 cm(sup -1) crystal field splitting of the S(sub 1) electronic state. The presence of pyridine in the grains can be confirmed spectroscopically. Pyridine produces a transmission window at 2175 A, matching exactly the well known UV hump. On grain reflection, some of the incoming UV radiation is absorbed into the grain's outer layers. Spikes in the lab and in the astronomical data are due to vibronic transitions in pyridine. The lab spectroscopy reported here clearly establishes the presence of MgTBP, H2TPB, and pyridine in the interstellar grains. The high fluorescence efficiency of MgTBP (being optically pumped in the visible) apparently accounts for all the observed UIR emissions.