scholarly journals Inhibition Effect of Atenolol on Copper Corrosion in 1M HNO3: Experimental Study and DFT

2021 ◽  
pp. 1-13
Author(s):  
Ehouman Ahissan Donatien ◽  
Bamba Kafoumba ◽  
Kogbi Guy Roland ◽  
Bamba Amara ◽  
Kouakou Adjoumani Rodrigue ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Quantum Chemical ◽  
Density Functional ◽  
Energy Gap ◽  
Copper Surface ◽  
Thermodynamic Quantities ◽  
Copper Corrosion ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Lowest Unoccupied Molecular Orbital

Atenolol was examined as a copper corrosion inhibitor in 1M nitric acid solution using the mass loss technique and quantum chemical studies, based on density functional theory (DFT) at the B3LYP level with the base 6-311G (d,p). The inhibitory efficiency of the molecule increases with increasing concentration and temperature. The adsorption of the molecule on the copper surface follows the modified Langmuir model. The thermodynamic quantities of adsorption and activation were determined and discussed. The calculated quantum chemical parameters related to the inhibition efficiency are the energy of the highest occupied molecular orbital E(HOMO), the energy of the lowest unoccupied molecular orbital E(LUMO), the HOMO-LUMO energy gap, the hardness (η), softness (S), dipole moment (μ), electron affinity (A), ionization energy (I), absolute electronegativity (χ),absolute electronegativity (χ), fraction (ΔN) of electrons transferred from Atenolol to copper and electrophilicity index(ω). The local reactivity was analyzed through the condensed Fukui function and condensed softness indices to determine the nucleophilic and electrophilic attack sites. There is good agreement between the experimental and theoretical results.

scholarly journals Quantum Chemical Studies on the Inhibiting Effect of Bipyrazoles on Steel Corrosion in HCl

2010 ◽  
Vol 7 (2) ◽  
pp. 419-424 ◽  
Author(s):  
K. Laarej ◽  
M. Bouachrine ◽  
S. Radi ◽  
S. Kertit ◽  
B. Hammouti
Keyword(s):  
Molecular Orbital ◽  
Quantum Chemical ◽  
Density Functional ◽  
Steel Corrosion ◽  
Chemical Parameters ◽  
Quantum Chemical Parameters ◽  
Highest Occupied Molecular Orbital ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Lowest Unoccupied Molecular Orbital

Correlation of the efficacy of some bipyrazoles,N,N-bis(3,5-dimethyl-pyrazol-1-ylmethyl)-cyclohexylamine (Bip 1),N,N-bis(3,5-dimethylpyrazol-1-ylmethyl)-ethanolamine (Bip 2),N,N-bis(3,5-dimethylpyrazol-1-ylmethyl) allylamine (Bip 3) andN,N-bis(3-carboethoxy-5-methylpyrazol-1-ylmethyl)-cyclohexylamine (Bip 4), against the corrosion of mild steel in HCl is discussed using density functional approach B3LYP/6-31G(d) calculations. The bipyrazole inhibitors exhibited the highest inhibition efficiency. The quantum chemical parameters calculated are, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), the gap energy (ΔE), the dipole moment (μ), the softness (σ) and the total energy (TE).

Computational and Experimental Study onthe Adsorption and Inhibition Effects of 1,3-Benzothiazol-6-ol on the Corrosion ofSteel X80 in Acidic Solution

2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Iman Danaee ◽  
Paria Nikparsa ◽  
Mohammad Reza Khosravi-Nikou
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Acidic Solution ◽  
Energy Gap ◽  
Force Microscopy ◽  
Highest Occupied Molecular Orbital ◽  
Low Concentrations ◽  
Noise Data ◽  
Chemical Factors ◽  
Lowest Unoccupied Molecular Orbital

Abstract In this work, the adsorption and inhibition behavior of 1,3-benzothiazol-6-ol were investigated by computational and experimental techniques for steel X80 corrosion in acidic solution. The density functional theory was carried out and quantum chemical factors like the energy gap, energy of highest occupied molecular orbital, the energy of lowest unoccupied molecular orbital, the fraction of electron transferred, and Mulliken charges have been calculated. In addition, according to quantum calculation, S atom in 1,3-benzothiazol-6-ol indicated more tendency for electrophilic attack in adsorption. The main reason for high inhibition efficiencies in very low concentrations is the planar and simplicity of inhibitor structure which leads to increasing the efficiency of adsorption by functional group especially sulfur. Electrochemical frequency modulation and potentiodynamic polarization indicated that this material has excellent inhibiting features in very low concentrations. The influence of DC trend on the explanation of electrochemical noise data was evaluated by polynomial fitting and the optimum polynomial order m = 5 was obtained. Noise resistance and the inhibition efficiency was calculated and compared in different methods. The theory of shot noise in frequency domain was used to obtain the electrochemical event charge. The corroded surface of steel in the absence and existence of thiazole compound was studied by Atomic force microscopy.

The Geometric and Electronic Structures of Fen-1Si(n=2-7) Clusters

2010 ◽  
Vol 150-151 ◽  
pp. 984-987
Author(s):  
Shuai Qin Yu ◽  
Li Hua Dong ◽  
Yan Sheng Yin
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Energy Gap ◽  
Energy Difference ◽  
Ground State Structure ◽  
Magic Numbers ◽  
Highest Occupied Molecular Orbital ◽  
Hybridization Intensity ◽  
Lowest Unoccupied Molecular Orbital ◽  
The Stability

The geometric structures and electronic properties of Si doped Fen (n=2-7) clusters have been systematically studied at the BPW91 level in density-functional theory (DFT). Calculated results show that an Si impurity does not change the ground-state structure of small iron clusters and prefers to occupy surface site bonding with iron atoms as many as possible. The second-order energy difference and the vertical ionization potential show that n=4 and 6 are magic numbers within the size range studied, but the maximum value occurs at n=4 for the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital(LUMO). It is found that the hybridization intensity between Si and Fe atoms is relevant to the stability of clusters.

scholarly journals Density Functional Theory Study of CL-20/Nitroimidazoles Energetic Cocrystal Compounds in an External Electric Field

2021 ◽  
Author(s):  
xiaosong Xu ◽  
Renfa Zhang ◽  
Wenxin Xia ◽  
Peng Ma ◽  
Congming Ma ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Electric Field ◽  
Nitro Group ◽  
External Electric Field ◽  
Molecular Orbital ◽  
Density Functional ◽  
Energy Gap ◽  
Functional Theory ◽  
Highest Occupied Molecular Orbital ◽  
Lowest Unoccupied Molecular Orbital

Abstract The external electric field has a significant influence on the sensitivity of the energetic cocrystal materials. In order to find out the relationship between the external electric field and sensitivity of energetic cocrystal compounds 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/1,4-dinitroimidazole (CL-20/1,4-DNI), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/1-methyl-2,4-dinitro-1H-imidazole (CL-20/2,4-MDNI) and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/1-methyl-4,5-dinitro-1H-imidazole (CL-20/4,5-MDNI). In this work, density functional theory (DFT) at B3LYP-D3/6-311+G(d,p) and M062X-D3/ma-def2 TZVPP levels was employed to calculate the bond dissociation energies (BDEs) of selected N-NO2 trigger bonds, frontier molecular orbitals, electrostatic potentials (ESPs) and nitro group charges (QNO2) under different external electric field. The results show that as the positive electric field intensity increases, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy gap and BDEs become smaller, and the local positive ESPs becomes larger, so that the energetic cocrystals tends to have higher sensitivity. In addition, the linear fitting results show that the trigger bond length and nitro group charge changes are closely related to the external electric field strength.

scholarly journals Theoretical and X-ray diffraction studies of organic photovoltaic compounds

2014 ◽  
Vol 70 (a1) ◽  
pp. C996-C996
Author(s):  
Abdelkader Chouaih ◽  
Salem Yahiaoui ◽  
Nadia Benhalima ◽  
Manel Boulakoud ◽  
Rachida Rahmani ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Organic Semiconductor ◽  
Density Functional ◽  
Energy Gap ◽  
Three Dimensional ◽  
Basis Set ◽  
X Ray Diffraction ◽  
Hybrid Functional ◽  
X Ray ◽  
Lowest Unoccupied Molecular Orbital

The electronic and structural properties of thiazolic ring derivatives were studied using density functional theory (DFT) and X-ray diffraction in terms of their application as organic semiconductor materials in photovoltaic devices. The B3LYP hybrid functional in combination with Pople type 6-31G(d) basis set with a polarization function was used in order to determine the optimized geometries and the electronic properties of the ground state, while transition energies and excited state properties were obtained from DFT with B3LYP/6-31G(d) calculation. The investigation of thiazolic derivatives formed by the arrangement of several monomeric units revealed that three-dimensional (3D) conjugated architectures present the best geometric and electronic characteristics for use as an organic semiconductor material. The highest occupied molecular orbital (HOMO) . lowest unoccupied molecular orbital (LUMO) energy gap was decreased in 3D structures that extend the absorption spectrum toward longer wavelengths, revealing a feasible intramolecular charge transfer process in these systems. All calculations in this work were performed using the Gaussian 03 W software package.

Theoretical studies on lindqvist polyoxometalates [M6O19]n−(M = Mo, W, n=2; M = V, Nb, Ta, n=8) and derivatives: Electronic structures, stability and bonding

2017 ◽  
Vol 16 (06) ◽  
pp. 1750054 ◽  
Author(s):  
Xiao-Fang Su ◽  
Bo Zhu ◽  
Cai-Xia Wu ◽  
Li-Kai Yan ◽  
Zhong-Min Su
Keyword(s):  
Charge Density ◽  
Molecular Orbital ◽  
Electronic Structures ◽  
Density Functional ◽  
Geometrical Structure ◽  
Energy Gap ◽  
Lumo Energy ◽  
Functional Theory ◽  
Highest Occupied Molecular Orbital ◽  
Lowest Unoccupied Molecular Orbital

The geometrical and electronic structures of [M6O[Formula: see text]][Formula: see text] (M [Formula: see text] Mo, W, [Formula: see text]; M [Formula: see text] V, Nb, Ta, [Formula: see text]) and their derivatives were investigated by using density functional theory methods. The results indicate that the geometrical structure of [V6O[Formula: see text]][Formula: see text] is not different from other Lindqvist-type anions. The energy gap between highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) (HOMO[Formula: see text]LUMO energy gap) of [V6O[Formula: see text]][Formula: see text] is smaller than those of same charge anions, [Nb6O[Formula: see text]][Formula: see text] and [Ta6O[Formula: see text]][Formula: see text]. In addition, the charge density [Formula: see text] of [V6O[Formula: see text]][Formula: see text] is larger when compared with those of other studied clusters. The investigation on the derivatives shows that the valence of V atom (V[Formula: see text] or V[Formula: see text]) and the methoxy ligand influence the HOMO[Formula: see text]LUMO energy gap and the charge density [Formula: see text] of the studied clusters.

scholarly journals QUANTUM CHEMICAL STUDIES ON BINDING OF cis-[PtCl2(iPram)(Hpz)] TO GUANOSINE

2018 ◽  
Vol 55 (6A) ◽  
pp. 51
Author(s):  
Pham Vu Nhat
Keyword(s):  
Quantum Chemical ◽  
Density Functional ◽  
Spectroscopic Properties ◽  
Basis Sets ◽  
Purine Base ◽  
Base Site ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Correlation Consistent ◽  
Consistent Basis

Quantum chemical calculations are employed to examine the interactions of hydrolysis products of cis-[PtCl2(iPram)(Hpz)] with the purine base site of DNA using guanosine as a model reactant. Thermodynamic parameters, electronic structures, bonding characteristics and spectroscopic properties of the resulting complexes are investigated in the framework of density functional theory (B3LYP functional) along with correlation consistent basis sets. Computed results show that these interactions are dominated by electrostatic effects, namely H-bond contributions. Another remarkable finding is that the replacement of amine groups by larger ones accompanies with a moderate reaction between PtII and guanosine.

Sign in / Sign up

Export Citation Format

Share Document