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Nitrosyl isomerism in amorphous Mn(TPP)(NO) solids.
Tigran S Kurtikyan1, Vardan A Hayrapetyan, Garik G Martirosyan
1Molecule Structure Research Center (MSRC), National Academy of Sciences, 0014, Yerevan, Armenia. kurto@netsys.am
Chemical Communications (Cambridge, England)
|November 13, 2012
Summary
Manganese tetraphenylporphyrin (Mn(TPP)) reacts with nitric oxide (NO) to form two isomers that switch between linear and bent structures with temperature changes. Computational studies reveal distinct electronic states for each isomer.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Computational Chemistry
Background:
- Amorphous manganese tetraphenylporphyrin (Mn(TPP)) layers are known to interact with small molecules.
- Nitric oxide (NO) is a biologically and chemically significant molecule with diverse coordination modes.
Purpose of the Study:
- To investigate the reaction products of amorphous Mn(TPP) with NO.
- To characterize the structural and electronic properties of the resulting Mn(TPP)(NO) isomers.
- To explore the temperature-dependent interconversion between these isomers.
Main Methods:
- Synthesis of amorphous Mn(TPP) layers.
- Exposure of Mn(TPP) layers to nitric oxide (NO).
- Characterization of Mn(TPP)(NO) isomers using spectroscopic and structural techniques (implied).
- Density Functional Theory (DFT) computations to predict electronic states.
Main Results:
- Formation of two Mn(TPP)(NO) isomers with distinct Mn-N-O geometries: linear and bent.
- Reversible interconversion between the linear and bent isomers upon changes in temperature.
- DFT calculations predict a singlet ground state for the linear isomer and a triplet state for the bent isomer.
Conclusions:
- The reaction yields stable Mn(TPP)(NO) isomers with temperature-dependent interconversion.
- The observed structural differences correlate with distinct electronic ground states (singlet vs. triplet).
- This study provides insights into the coordination chemistry of Mn(TPP) with NO and the influence of geometry on electronic structure.
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