Combining Experimental and Quantum Chemical Study of 2-(5-Nitro-1,3-Dihydro Benzimidazol-2-Ylidene)-3-Oxo-3-(2-Oxo-2H-Chromen-3-yl) Propanenitrile as Copper Corrosion Inhibitor in Nitric Acid Solution

Due to acidic solutions aggressiveness, corrosion inhibitors use is considered to be one the most practical methods to delay metals dissolution in the said solutions. In this study benzimidazolyl derivative namely 2-cyanochalcones 2-(5-nitro-1,3-dihydrobenzimidazol-2-ylidene)-3-oxo-3-(2-oxo-2H-chromen-3-yl) propanenitrile which was synthesized was then applied as a corrosion inhibitor for copper in 1 M HNO3 solution. The inhibition action of this molecule was evaluated by gravimetric and density functional theory (DFT) methods. It was found experimentally that this compound has a better inhibition performance and its adsorption on copper surface follows Langmuir adsorption isotherm. This adsorption evolves with temperature and inhibitor concentration, it is endothermic and occurs spontaneously with an increase in disorder. Corrosion kinetic parameters analysis supported by Adejo-Ekwenchi model revealed the existence of both physisorption and chemisorption. DFT calculations related that compound adsorption on copper surface is due to its electron donating and accepting capacity. The reactive regions specifying the electrophilic and nucleophilic attack sites were analyzed using Fukui and dual descriptor functions. Experimental results obtained were compared with the theoretical findings.

Molecular Design and Property Prediction of High Density 4-Nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate Derivatives as the Potential High Energy Explosives

To search for potential energetic materials with large energy density and acceptable thermodynamics and kinetics stability,twelve derivatives of 4-nitro-5-(5-nitro-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate(named A~L)are designed and analyzed by using density functional theory(DFT)calculations at the B3LYP/6-311G**level of theory.The molecular heats of formation(HOF),electronic structures,impact sensitivity(H_(50)),oxygen balance(OB)and density(ρ)are investigated by isodesmic reaction method and physicochemical formulas.Furthermore,the detonation velocity(D)and detonation pressure(P)are calculated to study the detonation performance by Kamlet-Jacobs(K-J)equation.These results show that new molecule J(H_(50)=36.9 cm,ρ=1.90g/cm^(3),Q=1912.46 cal/g,P=37.82 GPa,D=9.22 km/s,OB=0.00),compound A(H_(50)=27.9 cm,ρ=1.93 g/cm^(3),Q=1612.93 cal/g,P=38.90 GPa,D=9.19 km/s)and compound H(H_(50)=37.3 cm,ρ=1.97 g/cm^(3),Q=1505.06cal/g,P=37.20 GPa,D=9.01 km/s)present promising effects that are far better RDX and HMX as the high energy density materials.Our calculations can provide useful information for the molecular synthesis of novel high energy density materials.

Theoretical Study on the Nitrogen-rich Derivatives Based on 1,2,4-Triazole and 1,2,3-Triazole Rings:an Extended Family of Power Performance Energetic Materials

The geometric and electronic structures of the derivatives of 4-nitro-5-(5-nitroimino-1,2,4-triazol-3-yl)-2H-1,2,3-triazolate(named A~J)are explored employing density functional theory(DFT)calculations at the B3LYP/6-311G^(**)level of theory.Based on the optimized molecular structures,the heats of formation(HOF)are obtained,and the electronic properties,density and molecular sensitivity by characteristic heights(H_(50))are discussed.Besides,the detonation performances(detonation velocity,detonation pressure)are estimated via Kamlet-Jacobs(K-J)formula.Compounds B(H50=29.4 cm,ρ=1.91 g/cm^(3),Q=1563.04 cal/g,P=36.05 GPa,D=8.95 km/s)and H(H_(50)=31.9 cm,ρ=1.80 g/cm^(3),Q=1610.09 cal/g,P=37.31 GPa,D=9.12 km/s)have positive HOFs and remarkable insensitivity and good detonation performance,strongly suggesting them as the acceptable new-type explosive.The initiating power surpasses conventional primary explosives,such as HMX.The outstanding detonation power of compounds B and H contributes to its future prospects as a promising green primary explosive.

Determination of Cationic Surfactant by Laser Thermal Lens Spectrometry

A novel method for the determination of cationic surfactant by laser thermal lens spectrometry was developed. It was based on the reaction between 1-hydroxy-2-(5-nitro-2-Pyri- dylazo)-8-aminonaphthalene-3,6-disulfonic acid (5-NO2-PAH) and cationic surfactant to form 1:2 ionic association complex in a weakly basic medium (pH 9.44). The determination conditions and the mechanism were discussed. The method has been applied to the analysis of wastewater and moat water samples.