TITLE:
DNA Base Pairs Sensors: DFT, QTAIM and NCI-RDG Study
AUTHORS:
Nour Elyakine Amraoui, Dalila Hammoutène
KEYWORDS:
Density Functional Theory (DFT), Sensors, Quantum Theory of Atoms in Molecules (QTAIM), Non-Covalent Interaction Reduced Density Gradient (NCI-RDG), Potential Energy Surface (PES)
JOURNAL NAME:
Computational Chemistry,
Vol.12 No.4,
October
31,
2024
ABSTRACT: This work aims to present a theoretical study of sensor candidate formed from Cytosine-Cu-Cytosine at DFT/BP86/ZORA/DZP level using ADF code for the significance of proposing complexes based on DNA that captures toxic adducts in the gas phase as: CO, CO2, NO, HCN, SO2, H2S and NO2. The interaction between adducts and Cytosine-Cu-Cytosine complex was analyzed by QTAIM based on electronic density ρ(r) and Laplacian of electronic density ∇2ρ(r). NCI-RDG analysis was performed and discussed. Interaction of adducts with Cytosine-Cu-Cytosine complex takes place with a transition state, and the energy barrier is lower with CO2 E(TS) = 0.26 (kcal/mol). Potential energy surface (PES) gives saddle point for the formation of two bonds Cu-N and Cu-C at E = −6.826 a.u, Cu-N = 1.96 Å and Cu-C = 2.38 Å during the interaction of HCN with Cytosine-Cu-Cytosine complex. PES analysis proved that the interaction of NO2 with Cytosine-Cu-Cytosine achieves stabilization at E = −6.781 a.u,
Cu-N
NO
2
= 2.057 Å and
O
NO
2
…H23 = 1.90 Å.