![MOLECULAR STRUCTURES AND THERMODYNAMICAL CHARACTERISTICS OF M(V) (M= V, CR, MN, FE) MACROCYCLIC COMPLEXES CONSISTING [BENZO]ANNELATED PORPHYRAZINES AND NITRIDO LIGANDS: ANALYSIS USING DENSITY FUNCTIONAL THEORY](/upload/84d3a89c18d437fa8a9ddc6bbecb2e79/issues/cover/54112fd663ea6bd04835667de041d3de.jpeg)
MOLECULAR STRUCTURES AND THERMODYNAMICAL CHARACTERISTICS OF M(V) (M= V, CR, MN, FE) MACROCYCLIC COMPLEXES CONSISTING [BENZO]ANNELATED PORPHYRAZINES AND NITRIDO LIGANDS: ANALYSIS USING DENSITY FUNCTIONAL THEORY
Rubrics: 1. CHEMISTRY
Authors:
1.
Nacional'nyy Issledovatel'skiy Centr “Kurchatovskiy Institut”
2.
KNITU
Type:
Article
Pages:
from 37
to 47
Status:
Published
Received:
20.02.2026
Accepted:
16.03.2026
Published:
05.04.2026
Language:
Russian
Keywords:
ANADIUM, CHROMIUM, MANGANESE, IRON, MACROCYCLIC CHELATE, PORPHYRAZINE, TRANS-DI[BENZO]PORPHYRAZINE, NITRIDO LIGAND, DFT
Funding:
Vklad avtora D.V. Chachkova byl podderzhan v ramkah gosudarstvennogo zadaniya NIC “Kurchatovskiy Institut”.
Abstract:
Using the data of quantum chemical calculations obtained using the density functional theory (DFT) with the OPBE/TZVP and B3PW91/TZVP levels, the fundamental possibility of the existence of heteroligand complexes of the general formula [ML(N)], where L is trans-di[benzo]porphyrazine (DBP) or tetra[benzo]porphyrazine (TBP), M = V, Cr, Mn, Fe, is shown. The key parameters of the molecular structures (bond lengths, valence and non-valence angles) were determined for each of these compounds. It was noted that the chelate nodes MN4 have a square-pyramidal structure with a planar orientation of the nitrogen atoms in their composition; 5-membered and 6-membered non-chelate rings have a strictly planar structure, whereas 6-membered chelate rings are non-coplanar, with the sum of the internal valence angles deviating from the sum of the internal angles in a planar hexagon by no more than 5°. NBO analysis of these compounds was performed, and based on its data, a high degree of delocalization of the electron density in them was found. Standard thermodynamic parameters of formation (standard enthalpy DH 0f, 298 , entropy S 0f, 298 , and Gibbs energy DG 0f, 298 ,) were also calculated for the macrocyclic compounds under consideration. Based on these data, it was concluded that complexes V are the most stable of them, with their stability decreasing upon passing from M= V to M= Cr, increasing from M= Cr to M= Mn, and decreasing again from M=Mn to M=Fe. Good agreement was also noted between the structural parameters obtained using the two above-mentioned alternative versions of density functional theory.
Using the data of quantum chemical calculations obtained using the density functional theory (DFT) with the OPBE/TZVP and B3PW91/TZVP levels, the fundamental possibility of the existence of heteroligand complexes of the general formula [ML(N)], where L is trans-di[benzo]porphyrazine (DBP) or tetra[benzo]porphyrazine (TBP), M = V, Cr, Mn, Fe, is shown. The key parameters of the molecular structures (bond lengths, valence and non-valence angles) were determined for each of these compounds. It was noted that the chelate nodes MN4 have a square-pyramidal structure with a planar orientation of the nitrogen atoms in their composition; 5-membered and 6-membered non-chelate rings have a strictly planar structure, whereas 6-membered chelate rings are non-coplanar, with the sum of the internal valence angles deviating from the sum of the internal angles in a planar hexagon by no more than 5°. NBO analysis of these compounds was performed, and based on its data, a high degree of delocalization of the electron density in them was found. Standard thermodynamic parameters of formation (standard enthalpy DH 0f, 298 , entropy S 0f, 298 , and Gibbs energy DG 0f, 298 ,) were also calculated for the macrocyclic compounds under consideration. Based on these data, it was concluded that complexes V are the most stable of them, with their stability decreasing upon passing from M= V to M= Cr, increasing from M= Cr to M= Mn, and decreasing again from M=Mn to M=Fe. Good agreement was also noted between the structural parameters obtained using the two above-mentioned alternative versions of density functional theory.
Keywords:
ANADIUM, CHROMIUM, MANGANESE, IRON, MACROCYCLIC CHELATE, PORPHYRAZINE, TRANS-DI[BENZO]PORPHYRAZINE, NITRIDO LIGAND, DFT
ANADIUM, CHROMIUM, MANGANESE, IRON, MACROCYCLIC CHELATE, PORPHYRAZINE, TRANS-DI[BENZO]PORPHYRAZINE, NITRIDO LIGAND, DFT
