Comparison of Cu3, Cu5, and Cu7 clusters as potential antioxidants: A theoretical quest

• Published in: Journal of molecular modeling Vol. 30; no. 5; p. 132
• Main Authors: Alipour, Batoul, Kassaee, Mohamad Zaman
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2024; Springer Nature B.V
• Subjects: Antioxidants; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Clusters; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Energy of dissociation; Free energy; Free radicals; Heat of formation; Molecular Medicine; Original Paper; Oxidizing agents; Quantum theory; Scavenging; Theoretical and Computational Chemistry; AIM analysis; DFT; Scavenging radical; Cluster; NBO; Copper; Antioxidant; Pro-oxidant
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-024-05933-0

Context Herein, we compare and contrast the dual roles of Cu n clusters ( n  = 3, 5, and 7 atoms) in scavenging or generating RO • free radicals from ROH at the theoretical levels (where R = H, methyl, ethyl, n- propyl, i- propyl, n- butyl, t- butyl, and phenyl). This investigation is performed in water media to mimic the actual environment in the biological system. In the presence of the Cu n clusters, bond dissociation energy (BDE) of RO–H and R–OH is reduced. This is clear evidence for the increased possibility of both the RO–H and R–OH bonds breakage and scavenging of RO • radicals. The nature of anchoring bonds responsible for the interaction of Cu n clusters with ROH and RO • are interpreted using the quantum theory of atoms in molecules (QTAIM) and the natural bond orbital (NBO) analysis. The DFT results indicate that the O • ⋅⋅⋅ • Cu bond is stronger and has more covalent character in RO • ⋅⋅⋅ • Cu n radical complexes than in ROH⋅⋅⋅ • Cu n . Therefore, the interactions of Cu n clusters with RO • radicals (antioxidant) are more pronounced than their interactions with ROH non-radicals (pro-oxidant). Methods The GAMESS software package was utilized in this paper. The B3LYP and M06 functions with the 6–311 +  + G(d,p), and LANL2DZ/SDD basis sets was used to perform the important geometrical parameters of RO • ⋅⋅⋅ • Cu n and ROH⋅⋅⋅ • Cu n , binding energy (E b ), and bond dissociation energy (BDE). Graphical Abstract