Bond Parameters Research Articles

Application of Hansen solubility parameters in the eutectic mixtures: difference between empirical and semi-empirical models

Hansen Solubility Parameters (HSPs) are widely used as a tool in solubility studies. Given the variety of existent approaches to predict these parameters, this investigation focused on estimating the HSPs of a set of Natural Deep Eutectic Systems (NADES), using empirical (EM) and semi-empirical models (SEM), and then understanding their differences/similarities. Although these theoretical models are designed and recommended mostly for simple molecules or simple solutions, they are still being used in eutectic systems studies, mainly empirical ones. Thus, a preliminary test was conducted with a set of conventional solvents, in which their experimental values of HSPs are known. Besides the confirmation of the EM as the most suitable for these kinds of regular solvents, the results found also showed a very similar behaviour to what was observed in NADES, i.e., in terms of suggesting the EM and SEM with the highest/lowest similarity. Furthermore, it was concluded that although there is a large discrepancy between the estimated values of the hydrogen bond parameter, especially for systems with a higher polar character, there is still a good similarity for the other parameters. In fact, it was observed that, when combining the semi-empirical models, it was possible to obtain a value of the hydrogen bond parameter more similar to the empirical ones.

SYNTHESIS, STRUCTURAL CHARACTERIZATION, DFT AND DOCKING STUDIES OF 4, 5- DIPHENYL-1-(2 (PYRROLIDIN-1- YL)-ETHYL-2 (P-TOLYL)-1H-IMIDAZOLE

A novel crystal compound of 4,5-Diphenyl-1-(2-(pyrrolidin-1-yl)- ethyl-2(p-tolyl)-1H-imidazole (DPEI)inventive is experimentally calculated by FT-IR and FT-Raman. The compound affirmed sole crystal XRD investigation and upgraded bond parameters were computed hypothesis (DFT) at B3LYP/6-311++G (d,p)—the enhanced acquired by DFT calculations appreciable tolerance sole gem XRD information. The HOMO-LUMO exhibit conveys conjugation deep in the particle. Molecular Electrostatic Potential (MEP) guides the most reactive site. The synthesized target molecule (DPEI) is a latent NLO material since it has 18 times higher µß0 value than the standard. The obtained glide score value (-5.987kcal/mol) indicated the survival of effective reciprocal action between the DPEI molecule and the 1X02 anticancer protein. The cytotoxicity effect of the DPEI molecule against HepG2 (liver cancer cell line) revealed that the target molecule is a better candidate for the anti-cancer activity.

Research on the Calibration Method of the Bonding Parameters of the EDEM Simulation Model for Asphalt Mixtures

To enhance the accuracy and reliability of the discrete element simulation software EDEM 2023 for pavement asphalt mixture simulation, three representative coarse aggregate particles were modeled in 3D using the SolidWorks 2018 software and imported into the EDEM 2023 software for particle filling. The Hertz–Mindlin with bonding contact model was used to construct the EDEM simulation model of asphalt mixtures, and the quadratic regression model of asphalt mixtures’ splitting tensile strength and four bonding parameters, namely, normal stiffness per unit area, shear stiffness per unit area, critical normal stress, and critical shear stress, was found by the response surface methodology. The results show that the relationship between the significance magnitude of the four bonding parameters on the splitting tensile strength of the asphalt mixture simulation model is as follows: critical normal stress > shear stiffness per unit area > normal stiffness per unit area > critical shear stress. The calibration results of the bonding parameters were used for simulation verification, and the relative error between the simulation and actual splitting tensile strength was only −2.48%. The feasibility of this bonding parameter calibration method is demonstrated, and it can lay a foundation for EDEM to simulate the performance of asphalt mixtures on pavements with high-precision simulation.

Correlation between chemical bond characteristics and microwave dielectric properties of KLa(MoO4)2 ceramics

This investigation details the synthesis process of KLa(MoO4)2 ceramic utilizing a solid-state route method, alongside an analysis of its structural characteristics and the correlation between chemical bonds and microwave dielectric properties. The KLa(MoO4)2 phase was identified to possess a Monoclinic structure (C2/c space group). Sintering the sample at 820 °C resulted in a maximum relative density of 94.6 % and impressive microwave characteristics: εr = 9.63, Q × f = 50,100 GHz, and τf = −75.7 ppm/°C. Correlations between relative density and dielectric properties were observed. Further, application of the P-V-L bond theory facilitated the analysis of chemical bond parameters and their impact on microwave dielectric properties. The dielectric properties were correlated to chemical bond iconicity, packing fraction, lattice energy and bond valences.

Structure characteristics and microwave dielectric properties of ultra-low firing Li1.6(Mn1-xZnx)2.2(MoO4)3 ceramics

New Li1.6(Mn1-xZnx)2.2Mo3O12 (0.0≤x ≤ 1.0) ceramics were synthesized using the solid phase method. XRD results show that all samples adopt a Li1.6Mn2.2Mo3O12 single-phase structure. The Rietveld refinement results reveal that the reduction in lattice parameters is primarily due to the compression of [Li/Mn/ZnO₆] polyhedra. The relationship between chemical bond parameters and microwave dielectric properties was discussed using the Phillips–Van Vechten–Levine (PVL) theory. It is observed that introducing Zn2⁺ ion leads to twisting deformation of the [MoO4] tetrahedron and changes in the chemical bond lengths. As the x value increasing, polarizability per unit volume(α/Vm), bond ionicity fi(Mo1-O(1)), lattice energy ULi/Mn/Zn(3)-O(1)1 and bond energy E(Mo1-O(1)) exhibit trends similar to εr, Q × f and τf, indicating that changes in α/Vm and chemical bond parameters in the Li1.6(Mn1-xZnx)2.2Mo3O12 ceramics are intrinsic factors affecting the microwave dielectric properties. After sintering at 620 °C, the Li1.6(Mn0.2Zn0.8)2.2Mo3O12 ceramic exhibits outstanding microwave dielectric properties with εr = 5.22, Q × f = 60106 GHz, and τf = -58 ppm/°C, as well as good chemical compatibility with both Ag and Al metal electrodes, making it a promising candidate for ultra-low temperature co-fired ceramics (ULTCC).

Crystal structure, chemical bonds, and microwave dielectric properties of NaZnPO4 ceramic

This study reports the synthesis of NaZnPO4 ceramics using the solid-state reaction method and investigates their microwave dielectric properties for the first time. XRD analysis confirmed the formation of single-phase NaZnPO4 ceramic with a monoclinic structure. Among the samples, the one sintered at 850 °C exhibited the highest relative density of 95.4% and demonstrated excellent microwave dielectric properties, including a εr of 6.4, a Q × f of 49,500 GHz, and a τf of -47.3 ppm/°C. The measured εr values closely aligned with theoretical predictions, suggesting that molecular polarization significantly influences the relative dielectric constant. Furthermore, variations in sintering temperature primarily affected εr and Q × f through changes in relative density. Utilizing the P-V-L theory, we elucidated the relationship between chemical bond parameters and microwave dielectric properties, establishing that the P-O bond plays a dominant role in the dielectric behavior of the ceramics. Additionally, Raman spectroscopy results indicated that P-O bond vibrations predominated the entire spectrum.

Cocrystal screening of benznidazole based on electronic transition, molecular reactivity, hydrogen bonding, and stability.

Screening of cocrystals of active pharmaceutical ingredients is important in the development of pharmaceutical compounds because it improves bioavailability, stability, solubility, and many other physicochemical properties. In this work, quantum chemical calculations were utilized for the computational evaluation of the cocrystal screening of benznidazole (BZN) API via hydrogen bonding with four coformers (maleic acid, malonic acid, oxalic acid, and salicylic acid), and they contain carboxylic groups. The nitrogen of the imidazole ring in benznidazole and the carboxylic group of the coformer form a hetero-synthon connected by a strong hydrogen bond. The strength of the hydrogen bonding interaction O-H…N was measured using various tools. It was found that in comparison to BZN cocrystals with malonic acid, oxalic acid, and salicylic acid, the O-H…N interaction in the BZN-maleic acid cocrystal had higher interaction energy, indicating it had stronger hydrogen bonding. The strength of the hydrogen bond O-H…N for synthons was discovered to be more beneficial than the C-H…O interaction, as confirmed by ESP analysis. The BZN-salicylic acid cocrystal was found to be more reactive and polarizable, whereas the BZN-malonic acid cocrystal was more stable. Cocrystals of benznidazole exhibited better physicochemical characteristics than API benznidazole, as indicated by electron transition properties between the most significant orbitals. The computational evaluation for the screening of benznidazole cocrystals was performed in Gaussian 16 software using density functional theory (DFT) with the hybrid functional B3LYP and the basis set 6-311 + + G(d,p). The UV-Vis absorption spectrum in solvent water was analyzed using the TD-DFT/6-311 + + G(d,p) method to determine the influence of the solvent in cocrystals using a polarizable continuum model. The strength of the hydrogen bonding interactions O-H…N in each of those mentioned cocrystals was used to screen the cocrystals using tools such as thermodynamic probability, ESP analysis, QTAIM analysis, and NBO analysis. The pairing energy of interaction was measured by determining H-bond donor ( ) and H-bond acceptor ) parameters for hydrogen bonds from maxima and minima on the ESP surface. GaussView 06 software was used to create, visualize, and plot the optimized structure of the cocrystal and HOMO-LUMO orbitals. The AIMALL (10.05.04) software package generated the molecular graph for intra- and intermolecular interactions. The RDG-scatter plot, MEP map, and ELF plot were rendered from Multiwfn 8.0 and VMD 1.9.1 software.

Rational design, synthesis, computational studies and biological evaluation of new diazepanone derivatives: Crystal structure of 2,7-bis(4-chlorophenyl)-1,3-dimethyl-1,4-diazepan-5-one

Structural and biological evaluation of newly designed and synthesized diazepanone derivatives (3a-c) with modified functionalities is reported in this paper, as liponucleoside class of antibiotics possessing 1,4-diazepanone as core moiety are under investigation since last decade to improvise their drug action. FT-IR, HR-ESI-MS, 1H NMR and 13C NMR spectral studies are used for the structural characterization of synthesized compounds (3a-c). 1H NMR spectral data reveal that the diazepanone ring exhibits chair conformation in solution state. The solid state geometry for compound 3a acquired by SC-XRD study also in favour of chair conformation of the diazepanone ring with equatorial orientation of all the substituents. Comparison of experimental bond parameters with theoretical results attained by DFT studies using B3LYP/6–311G++ (d,p) basis set are in good agreement. Molecular electrostatic potential surface (MEPS) and HOMO-LUMO energies are used to elucidate the topology and physicochemical parameters of 3a. Nature of crystal packing is ascertained by Hirshfeld surface and its delineated 2D-Fingerprint plot in addition with the SC-XRD evidences. Antibacterial evaluation of (3a-c) against tested bacterial strains reveals that the compounds have remarkable antibacterial potencies compared to tested standard drug. Among the compounds 3a-c, the compound 3c with fluoro-substitution on the phenyl ring shows highest activity.

Unlocking the potential of borophene nanoribbons for efficient hydrogen storage

This research explores the structural, electronic, optical, and hydrogen storage properties of borophene nanoribbons (BNRs) with armchair (ANR-B-H) and zigzag (ZNR B-H) edges. Computational simulations optimized these structures, revealing that 7ZNR-B-H has a superior binding energy. Chemical modifications, such as fluorine passivation and functionalization, influenced bond parameters and quantum properties. Bilayer BNRs showed increased stability and enhanced electrical conductivity. Our study demonstrated promising hydrogen storage capabilities, with passivated and functionalized BNRs achieving suitable adsorption energies and a significant gravimetric storage capacity of 20.32 wt%, exceeding DOE standards. NH2 functionalization notably improved adsorption energy, enhancing potential for efficient hydrogen storage. Changes in absorption spectra post-H2 adsorption further highlight BNRs’ potential for hydrogen storage applications. These findings provide valuable insights into BNRs, paving the way for their use in electronic devices and hydrogen storage systems.

Field-Induced Quantum Criticality in Two-Coupled Two-Leg Heisenberg Ladders

We use the bond mean field theory, which is based on the Jordan–Wigner fermionization, to investigate the quantum critical behavior of a system composed of two-coupled Heisenberg Spin-[Formula: see text] two-leg ladders in the presence of an applied magnetic field. By examining the dependence of the ground state on the magnetic field for different coupling constants, we investigate the field-induced quantum criticality. The magnetization exhibits distinct plateaus: a zero magnetization plateau for fields below a threshold value of the field [Formula: see text] and a saturation plateau for fields exceeding a second critical value [Formula: see text]. The spin bond parameters are calculated and found to show a critical behavior at [Formula: see text].

Enhancing detection of thermal runaway gases: Exploiting doping and vacancy effects in GeS quantum dots

This study investigates chemical modifications on Germanium Sulfide (GeS) quantum dots (QDs) for selective detection of thermal runaway gases (TRGs). We examine how doping with oxygen, phosphorus, silicon, and introducing sulfur vacancies at edge and surface regions affect the structural, electronic, and optical properties of GeS-QDs and their derivatives. Our findings reveal significant changes in bond parameters, formation energy, electronic band gap, and light absorption behavior. Oxygen doping enhances stability, while other dopants and sulfur vacancies increase reactivity towards TRGs (H2, CO, CH4, C2H4). All materials show favorable adsorption for these gases, with C2H4 displaying the strongest binding affinity. Adsorption minimally affects core electronic structure (HOMO) but shifts surface electronic states (LUMO). Sulfur vacancies reduce the energy gap, enhancing conductivity and facilitating TRGs detection. These results suggest that GeS-QDs can be effectively tuned for selective TRG detection by manipulating their chemical composition and surface characteristics.

Exploring the graphitization transformation mechanism of deposited carbon in molten salt electrolysis: A novel insight from molecular structure models

Molten salt electrolysis graphitization is a novel method for the electrochemical graphitization, offering significant technological advantages. Researchers have shown keen interest in preparing graphite materials through molten salt strategies. However, there is still a lack of comprehensive research methodologies at the molecular scale for the removal of heteroatoms and rearrangement of carbon atoms in different amorphous carbon conversion systems. To address the above issue, the deposited carbon (DC, a coking byproduct) was converted into graphitized material (electrolysis products, EP) through the electrochemical method in this study. By processing Transmission Electron Microscope images with Python programming, aromatic skeleton structure information was quantitatively extracted. The evolution of the structure of DC was studied using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Based on information about elemental content, aromatic skeletal structure, and heteroatom functional groups, average chemical structure models were constructed for DC and EP, and relevant chemical bond parameters were statistically analyzed. Then, the influence of the electric field on the structural transformation of amorphous carbon in molten salts was investigated. The research results show that the electric field significantly affects the graphitization transformation process of amorphous carbon in molten salts, enhancing the interaction between calcium ions and DC molecules, increasing the diffusion coefficient of particles in the system, and promoting the formation of more sp2-hybridized carbon atoms, thus forming a more compact aromatic ring network. This study provides a new research method and molecular/atomic-level insights for a deeper understanding of the mechanism of graphitization transformation of amorphous carbon.

Synthesis and anticancer activity of Pd(II) and Pt(II) complexes of dodecyl based dithiocarbamate ligands: Insight into the C-H∙∙∙Pt interaction using X-ray structure, DFT, Hirshfeld surface and AIM analysis

Four new homoleptic complexes bis(N-dodecyl-N-benzyl)dithiocarbamato-S,S’)M(II) (where M=palladium (1), platinum (3)) and bis(N-dodecyl-N-(2-hydroxybenzyl)dithiocarbamato-S,S’)M(II) (where M=palladium (2), platinum (4)) were synthesized and characterized using elemental analysis, FTIR and NMR spectra. The crystal structures of 1 and 4 were solved by single crystal X-ray diffraction technique. Single crystal X-ray analysis of the two of the complexes (1 and 4) revealed the presence of a distorted square planar coordination geometry (S4) about the metal centre. Complex 4 revealed two intermolecular anagostic C-H∙∙∙Pt interactions which were characterized through a comprehensive set analysis using single crystal X-ray diffraction (experimental) and DFT, Hirshfeld surface analysis and AIM (theoretical) analysis. The electronic behavior, MEP surfaces, FMO and DOS studies of the complexes 1 and 4 were investigated employing DFT. A strong correlation has been found between both experimental and theoretical bond parameters. MTT assay was used to study the antitumor activities of 1–4 against MCF7 cancer cells. The results reveal that all complexes have fine anticancer activities.

Plasticity and strength of an equiatomic and a non-equiatomic HfNbTaTiZr high entropy alloy during uniaxial loading : a molecular dynamics simulation study

Abstract Understanding plasticity and strength of high entropy alloys of HfNbTaTiZr is extremely significant in building nuclear reactors, gas turbines, aerospace devices etc. Here we study an equiatomic (Hf0.20-Nb0.20-Ta0.20-Ti0.2-Zr0.20) and a non-equiatomic (Hf0.35-Nb0.20-Ta0.15-Ti0.15-Zr0.15) mixture of two alloys under uniaxial tensile loading from molecular dynamics simulations. Modified Embedded atom potential is used to model both these bcc alloys and all simulations are performed at 300 K with three different tensile strain rates–0.0002, 0.0005 and 0.001 ps−1. Radial distribution functions, bond-orientational parameters and OVITO are used to analyse the MD trajectories. At 0.001 ps−1 strain, both these alloys deform similarly, but differences are observed at 0.0005 and 0.0002 ps−1 strains. At these rates, both alloys deform elastically till 3%, thereafter they deform plastically till 15%–20% strain. Yield strengths are comparable in the elastic limit but in the plastic limit non-equiatomic alloy have higher strength. In equiatomic alloy, bcc phase transforms to fcc whereas in non-equiatomic alloy bcc phase transforms to both fcc and hcp. Formation of hcp atoms (50%) decrease the plasticity of the non-equiatomic alloy but increases its strength. We also observe that in both these alloys and at all strain rates, bcc atoms transform to fcc/hcp atoms through an intermediate amorphous like state. Local coordination and orientation of all atoms change similarly in equiatomic mixture. But in non-equiatomic mixture local orientation in Hf, Ti and Zr changes differently compared to Nb and Ta.

Low-loss and low-temperature sintering of SrNb2V2O11 with a large positive τf value as an effective temperature compensator

Novel SrNb2V2O11 microwave dielectric was synthesized and proposed as a temperature compensator for Low-temperature cofired ceramics (LTCC)/Ultra-low-temperature cofired ceramics (ULTCC) applications. The X-ray diffractometer (XRD) patterns matched well with the SrNb2V2O11 phase, exhibiting a monoclinic structure and Cc space group over the entire experiment. The presence of the Nb-rich second phase at 850 °C was attributed to the melting of the samples. The microwave dielectric properties were highly correlated with the chemical bond parameters, which were intensively investigated using the P-V-L theory. The specimen sintered at 820 °C reveals dielectric properties, combining an εr of 74.5, Q × f of 13,000 GHz, and τf of 517 ppm/°C. The large positive τf can make the ceramic an effective temperature compensator for LTCC applications. Moreover, the medium-high εr value can also act as a practical material for dielectric resonators used in the base stations, where a stable environment and limited temperature changes are crucial.

Experimental and analytical investigations on debonding response of embedded through-section ribbed GFRP bar-to-concrete joints at elevated temperatures

Embedded Through-Section (ETS) technique has gained a great deal of increasing interest in the shear strengthening of existing reinforced concrete members, which is based on using fibre-reinforced polymer (FRP) bars installed through predrilled holes into concrete via adhesive. One of the key issues associated with the bonding of ETS FRP bars to concrete is the debonding of FRP bar-to-concrete interfaces which leads to premature and brittle failure of strengthened members, particularly under elevated temperatures. However, little research has been conducted on the influence of elevated temperatures on the bond behavior between ETS FRP bars and concrete. This paper presents experimental and analytical evaluations of the bond response of ETS-ribbed glass FRP (GFRP) bar-to-concrete joints subjected to elevated temperatures. A total of 90 pullout specimens were tested to quantify the influences of the temperature, bar diameter, and concrete strength on the failure mode, load response and bond strength. An analytical model to reproduce the full-range debonding process of ETS-GFRP bar-to-concrete interfaces was presented, which allowed simultaneously considering both long and short embedded lengths, interfacial friction, and snap-back behavior. The load-slip response, stress field, and peak load were solved analytically, resulting in a closed-form solution for the critical length for snap-back and a non-closed-form solution for the effective embedment length. After an inverse analysis procedure was proposed for determining the bond parameters, the accuracy of the analytical solution was verified through comparisons with the self-conducted test results and existing experimental data. A new temperature-dependent bond strength model was also developed. The findings revealed a remarkable decline in the bond strength of up to 92.3 % as the temperature increased from 20 °C to 160 °C, with about 60–70 % of this degradation occurring close to the glass transition temperature (Tg) of the adhesive. At temperatures well above Tg, the bond strength decreased with the bar diameter and displayed insignificant improvement with higher concrete strength. The results also demonstrated that the proposed analytical approach and bond strength model can predict the bond response of ETS ribbed GFRP bars embedded in concrete with reasonable accuracy.

A comprehensive investigation on one-pot synthesis of imidazole derivatives: quantum computational analysis, molecular docking, molecular dynamics simulations and antiviral activity against SARS-CoV-2

New derivatives of 4-(2-(2-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-4,5-diphenyl-1H-imidazol-1-yl)ethyl)morpholine (DDIM) have been successfully synthesised and characterised using spectral methods such as FT-IR, 1H NMR, and 13C NMR. Density functional theory (DFT) with the B3LYP/6-311G (d, p) level of theory was used to determine optimised bond parameters and single crystal XRD investigations confirmed the structure of DDIM. The results of single crystal XRD measurements aligned well with the optimised geometrical parameters from DFT calculations. Frontier molecular orbital computations provided insights into the molecule's stability, chemical reactivity and charge transfer. Atomic charges were determined using mulliken population analysis. The molecular electrostatic potential (MEP) mapped to electron density surfaces identified potential reactive sites. This molecule shows promise as a potential NLO material due to its high μβ0 value. Binding affinities were determined via molecular docking against the COVID-19 major protease (Mpro: 6WCF/6Y84/6LU7). A 100 ns molecular dynamics simulation under in silico physiological conditions confirmed the stability of the complex structure formed with the COVID-19 protein, revealing a stable conformation and binding pattern in an imidazole derivative environment. Additionally, in-silico analysis predicted favourable to moderate anti-viral activity and anticipated the compound's absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles.

Research on the molecular structure, solvent effects, quantum computing, topology, and biological aspects of 4-phenylcoumarin-7-yl-methacrylate as an anticancer agent

The objective of this research is to conduct both experimental and theoretical analyses on the synthesis and characterization of a new coumarin derivative known as 4-phenylcoumarin-7-yl-methacrylate (PCMA). To accomplish this, several methods including 1H-NMR, FT-IR, and UV-visible spectroscopy were employed, and atomic charges and bond parameters were calculated using the DFT-B3LYP/6-311G++(d,p) basis set. Additionally, topological properties such as Electron Localized Function, Localized Orbital Locator and Non-Covalent interactions (RDG-NCI) were thoroughly examined. The TD-DFT approach was used to calculate the UV-Vis absorption technique in various solvent media, and the Light Harvesting Efficiency was also investigated. An analysis of Frontier Molecular Orbitals (FMO), Molecular Electrostatic Potential (MEP), and Average Local Ionization Energy (ALIE) simulations were conducted to identify the optimal sites for both electrophilic and nucleophilic attacks. Nonlinear Optical (NLO) behavior was also examined by determining the dipole moment (μ), the linear polarizability (α), first hyperpolarizability (β) and second hyperpolarizability (γ) through the use of the same basis set. To better understand molecular stability and interactions, Natural Bond Orbital (NBO) analysis was performed, providing insights into hyperconjugative interactions, charge delocalization, and electron density (ED) among the molecular components. Electron-hole and TDM analysis were also conducted to investigate the various types of electron-excited states. This research will additionally explore the drug-likeness and docking potential of PCMA, with the goal of determining its suitability as a potential candidate for cancer treatment. This comprehensive study offers valuable insights into the structural, electronic, and biological properties of 4-phenylcoumarin-7-yl-methacrylate (PCMA).

TOPO-decanoic acid based DES – Structural insights using DFT, physico-chemical investigations and extraction efficiency of DES diluted with chloroform

Deep eutectic solvents (DESs) are recently regarded as evolving candidates in the field of separation science in order to achieve sustainability. In the present work, hydrophobic TOPO-Decanoic acid DES has been synthesized and scrutinized by FTIR and 1HNMR studies. The structures of TOPO (Tri-octyl phosphine oxide), decanoic acid, chloroform, DES and DES + chloroform have been optimized employing B3LYP functional using DFT-D3 of Grimme’s method. The HOMO-LUMO (Eg) energy gap, bond lengths, mulliken charges,dipole moment and interaction energy has been evaluated using DFT. The geometry optimization provides the bond parameters which explain about the existence of non-bonded interactions. DES and DES + chloroform show more reactiveness as compared to its constituents evident from the chemical potential value. Physico-chemical properties such as density, volumetric (V), dielectric constant (ε), refractive index (nD) and ultrasonic velocity (U) of the hydrophobic TOPO-Decanoic acid DES diluted with polar cosolvent chloroform have been determined over a wide range of mole fraction of DES at 298.15 K. The excess properties such as VE, εE, nDE and UE have been calculated to predict the type of inter-molecular interaction existing within the components of the DES diluted chloroform mixture. Different mixing rules have been used to estimate properties such as dielectric permittivity, refractive index and ultrasonic velocity. Various acoustic parameters such as Z, βs, and (Lf)mix of binary mixtures are evaluated to predict about the presence of inter molecular interactions within the mixture components. The prepared hydrophobic eutectic mixture in chloroform has been further used for extraction of Y (III) and Eu (III). The solvent extraction of Eu (III) showed better performance as compared to that of Y (III).

Effects of structural changes of PPO and PEO of nonionic surfactants on oil–water interface properties: A molecular dynamics simulation study

The rapid progress of chemical flooding in recent years has imposed increasingly higher demands on the interface properties of surfactants. In this study, through analysis of interface properties, we investigated the influence of chain length and position of PO and EO chains on the surface activity of surfactants. It was observed that when the chain length was 10, both PO and EO chains exhibited the lowest interfacial tension. Principal component analysis was employed to reduce dimensionality for Rg (radius of gyration), tilt angle, and hydrogen bond parameters. Ultimately, it was found that Rg-PO, Rg-EO, and H-bond exerted significant influence on interfacial tension with decreasing weights successively. The correlation between tilt angle and its impact on interfacial tension was lower compared to these three factors mentioned above. Therefore, when designing surfactant structures, it is crucial to reasonably match the lengths of PO and EO chains.