NOVEL MACROCYCLIC METAL COMPLEXES CONTAINING OCTAFLUORO-SUBSTITUTED PORPHYRAZINE AND TWO AXIAL ACIDOLIGANDS: DESIGN USING DFT
Rubrics: 1. CHEMISTRY
Authors:
1.
KNITU
2.
KNITU
Type:
Article
Pages:
from 10
to 21
Status:
Published
Received:
22.12.2025
Accepted:
23.12.2025
Published:
23.12.2025
Language:
Russian
Keywords:
OCTAFFLUOROPORPHYRAZINE, FLUORO LIGAND, 3D METAL CHELATE, MOLECULAR STRUCTURE, DFT
Abstract (English):
Using three independent variants of the density functional theory (DFT) with the B3PW91, M06, and OPBE functionals and the TZVP basis set, the molecular structures of heteroligand (6666) macrotetracyclic chelates of 3d-elements of the [M(ofp)(F)2] type (M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu) with a doubly deprotonated form of the tetradentate macrocyclic ligand, octafluoroporphyrazine (ofp2-), and two axially oriented fluoro ligands were calculated. The values of the most important bond lengths, bond and non-bonded angles in the resulting metal complexes are presented. It was noted that, according to data from all the above-mentioned DFT methods, seven of these eight complexes have a planar MN4 chelate core and a planar macrocycle structure. Moreover, all 5-membered and 6-membered rings in each of these seven metal chelates are identical to each other (both in the sum of their bond angles and in their range). An NBO analysis of the coordination compounds under consideration, was performed, images of their highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals, as well as the values of the effective charges on individual atoms, are presented. The standard enthalpy, entropy, and Gibbs free energy of formation of these compounds were calculated. It was found that the values of the standard enthalpy and standard Gibbs energy for both the H2ofp ligand itself and the metal complexes it forms are negative, which indicates their high thermodynamic stability. Good agreement was also noted between analogous parameters calculated by various DFT methods, both qualitatively and quantitatively.
Using three independent variants of the density functional theory (DFT) with the B3PW91, M06, and OPBE functionals and the TZVP basis set, the molecular structures of heteroligand (6666) macrotetracyclic chelates of 3d-elements of the [M(ofp)(F)2] type (M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu) with a doubly deprotonated form of the tetradentate macrocyclic ligand, octafluoroporphyrazine (ofp2-), and two axially oriented fluoro ligands were calculated. The values of the most important bond lengths, bond and non-bonded angles in the resulting metal complexes are presented. It was noted that, according to data from all the above-mentioned DFT methods, seven of these eight complexes have a planar MN4 chelate core and a planar macrocycle structure. Moreover, all 5-membered and 6-membered rings in each of these seven metal chelates are identical to each other (both in the sum of their bond angles and in their range). An NBO analysis of the coordination compounds under consideration, was performed, images of their highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals, as well as the values of the effective charges on individual atoms, are presented. The standard enthalpy, entropy, and Gibbs free energy of formation of these compounds were calculated. It was found that the values of the standard enthalpy and standard Gibbs energy for both the H2ofp ligand itself and the metal complexes it forms are negative, which indicates their high thermodynamic stability. Good agreement was also noted between analogous parameters calculated by various DFT methods, both qualitatively and quantitatively.
Keywords:
OCTAFFLUOROPORPHYRAZINE, FLUORO LIGAND, 3D METAL CHELATE, MOLECULAR STRUCTURE, DFT
OCTAFFLUOROPORPHYRAZINE, FLUORO LIGAND, 3D METAL CHELATE, MOLECULAR STRUCTURE, DFT
