Structure, Stability, and Electronic Feature Analyses of Substrates (Methyl Orange and Vanadium Oxide)-Surfactant (Triton X-100) Complex: A Computational Insight

Abstract

Aims: The objective of the present work is to understand the structural stability (i.e., H-bonding and other weak noncovalent interactions) and electronic features of new model substrates, such as methyl orange (MO), vanadium oxide (V), surfactants as Triton-X100 (TX-100), and their allied substrate-surfactant model complexes (MO-V, MO-TX100, V-TX100, and (MO-V)-X100) with the deployment of density functional theory (DFT) method followed by electronic structure calculations and quantum theory of atoms in molecules (QTAIM) approaches. Background: Significant interactions appear to play a major role in reducing the energy gap between the model substrates Methyl Orange (MO)/Vanadium Oxide (V)/MO-V) and surfactant/catalyst Tri-ton-X100 (TX-100) and enhancing the catalytic behaviour of the surfactant/catalyst TX-100. Objective: The main objective of the present report is to conduct computational experiments on the designing, characterization, structure, stability, and electronic feature analyses of substrates-surfac-tant model complexes constituted from Methyl Orange (MO), Vanadium Oxide (V), Triton-X100 (TX-100) units which could indeed help in synthesizing novel materials as a catalyst, controlling the reaction path by tuning such interesting interactions between a catalyst/surfactant and substrate. Methods of Computational Calculations: The quantum chemical calculations have been performed using Gaussian 09 electronic structure calculations program. B3LYP exchange-correlation functional in conjunction with 6-31G(d,p) basis set has been employed along with the incorporation of the ef-fective core potential (ECP) based basis set for vanadium ‘V’ atom. Results: In the present report, the computational experiments have been conducted to probe the struc-tural, stability, and electronic features of four substrates-surfactant model complexes (SSMC) [MO-V, MO-TX-100, V-TX-100, and (MO-V)-TX-100] acquired from the substrates MO and V or the combination of both as MO-V and surfactant/catalyst TX-100. The HOMO-LUMO energy gap of the (MO-V)-TX-100 SSMC complex (0.679 eV) is found to be the lowest among all [MO-V (3.691 eV), MO-TX-100 (3.321 eV), and V-TX-100 (3.125 eV)] SSMCs, which appears mainly due to the presence of surfactant/catalyst (TX-100), thus showing its high reactivity/catalytic behaviour. Conclusion: The calculated binding energy, change in Gibbs free energy, natural charges, and the QTAIM based topological parameters show the most favourable stabilization (H-bonding and non-covalent interactions, including metal/non-metal bonding) and interactions in the (MO-V)-TX-100 SSMC, indicating the presence of the TX-100 surfactant.