(H,H)-Isomerism of cis- and trans-di[benzo]porphyrazines: Quantum chemical modeling within the framework of the DFT method

Quantum-chemical calculation of the molecular structures of potential isomeric (NNNN)- donoratomic macrocyclic tetradentate ligands, cis- and trans-di[benzo]porphyrazines, was carried out using the density functional theory (DFT) B3PW91/TZVP. It is noted that the first of these compounds can exist in four forms [so-called ([Formula: see text]-isomers], differing from each other by the mutual orientation of hydrogen atoms bonded to the nitrogen atoms, while the second compounds take the form of two similar isomers. The values of the most important bond lengths, bond and non-bond angles in each of these ([Formula: see text] -isomeric compounds, as well as the values of their relative energy, standard enthalpy, entropy, and Gibbs energy of formation are presented. It was found that the most stable among both cis- and trans-di[benzo]porphyrazines is the ([Formula: see text]-isomer with the trans-orientation of hydrogen atoms bonded to nitrogen atoms, while the ([Formula: see text] -isomers with cis-oriented hydrogen atoms for both of these compounds had significantly higher relative energies.

Raman spectra of rare earth double-decker complexes with porphyrinato and 2,3-naphthalocyaninato ligands

The Raman spectra of the mixed (naphthalocyaninato)[tetrakis(4-[Formula: see text]-butylphenyl)porphyrinato] rare earth double-decker compounds M(Nc)(TBPP) (M = Y, La, Ce, Eu, Dy, Lu) were studied with Density Functional Theory for the first time. The results reveal the fingerprint band for naphthalocyanine to be around 1455–1615 cm[Formula: see text] and porphyrin around 693–749 cm[Formula: see text]. Coupled Nc–Por ring–ring interaction vibration modes are also detected at 1470–1522 cm[Formula: see text], owing to the stretching between the central metal and the N atoms. These vibration modes are recognized as the dominating components in the Raman spectra of those double-decker compounds.