Alipour Batoul, Kassaee Mohamad Zaman
Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
J Mol Model. 2024 Apr 16;30(5):132. doi: 10.1007/s00894-024-05933-0.
Herein, we compare and contrast the dual roles of Cu 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 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 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 radical complexes than in ROH⋅⋅⋅Cu. Therefore, the interactions of Cu clusters with RO radicals (antioxidant) are more pronounced than their interactions with ROH non-radicals (pro-oxidant).
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 and ROH⋅⋅⋅Cu, binding energy (E), and bond dissociation energy (BDE).
在此，我们在理论层面比较并对比了铜簇（n = 3、5和7个原子）在从ROH清除或生成RO自由基方面的双重作用（其中R = H、甲基、乙基、正丙基、异丙基、正丁基、叔丁基和苯基）。该研究在水介质中进行，以模拟生物系统中的实际环境。在铜簇存在的情况下，RO - H和R - OH的键解离能（BDE）降低。这清楚地证明了RO - H和R - OH键断裂以及清除RO自由基的可能性增加。使用分子中的原子量子理论（QTAIM）和自然键轨道（NBO）分析来解释负责铜簇与ROH和RO相互作用的锚定键的性质。密度泛函理论（DFT）结果表明，在RO⋅⋅⋅Cu自由基络合物中，O⋅⋅⋅Cu键比在ROH⋅⋅⋅Cu中更强且具有更多的共价特征。因此，铜簇与RO自由基（抗氧化剂）的相互作用比它们与ROH非自由基（促氧化剂）的相互作用更显著。
本文使用了GAMESS软件包。采用B3LYP和M06函数以及6 - 311 + + G(d,p)和LANL2DZ/SDD基组来计算RO⋅⋅⋅Cu和ROH⋅⋅⋅Cu的重要几何参数、结合能（E）和键解离能（BDE）。
