Total Dipole Moment Research Articles

Synthesis, Characterization, DFT Study and Antifungal Activities of Some Novel 2-(Phenyldiazenyl)phenol Based Azo Dyes.

In recent decades, there has been an increased interest in azo compounds with special optical and biological properties. In this work, we report the preparation of novel azo-compounds with two and three -N=N- double bonds, using the classical method of synthesis, diazotization and coupling. The compounds were characterized by 1H-NMR, 13C-NMR, FTIR, UV-VIS and fluorescence spectra. DFT calculations were employed for determining the optical parameters, polarizability α, the total static dipole moment μtot, the quadrupole moment Q and the mean first polarizability βtot. All azo derivatives show strong fluorescence emission in solutions. The antioxidant and antifungal activities were determined and the influence of the number of azo bonds was discussed. The synthesized compounds exhibit remarkable efficiency in the growth reduction of standard and clinical isolated Candida strains, suggesting future applications as novel antifungal.

Molecular geometry, spectroscopic and NLO studies of 1-(chloromethyl)-4-fluorobenzene – A DFT study

The vibrational spectra of 1-(chloromethyl)-4-fluorobenzene have been studied in the 4000 - 400 cm -1 and 3500 - 50 cm -1 range, by FTIR and FT-Raman, respectively. In this work, structural analysis and vibrational frequencies are performed utilizing the GAUSSIAN 09W program with DFT/B3LYP strategy with basis set 6-311++G (d, p). Least differences are noted between the measured and scaled wavenumbers. The molecular vibrational assignments are confirmed by the PED (potential energy distribution) percentage. Frontier molecular orbital, natural bond orbital and Mullikan charge examinations are employed to explain the reason for intra and intermolecular charge exchange of the molecule. Reactive sites and chemical shifts are investigated by molecular electrostatic potential map and nuclear magnetic resonance analysis. Besides, the polarizability, the first hyperpolarizability, and total dipole moment of the molecule have been computed for describing its NLO activity.

Effective field theory of dipolar braiding statistics in two dimensions

A rank-2 toric code (R2TC) Hamiltonian in two dimensions can be constructed as a Higgsed descendant of rank-2 U(1) lattice gauge theory. As noted by the authors recently, [Y.-T. Oh, J. Kim, E.-G. Moon, and J. H. Han, Phys. Rev. B {\bf 105}, 045128] the quasiparticles in that model shows unusual braiding statistics that depends on the initial locations of the particles which participate in the braiding. We show that this new kind of statistical phase captures the total dipole moment of quasiparticles encompassed in the braiding, in contrast to the conventional anyonic braiding seeing the total charge. An Aharonov-Bohm interpretation of such {\it dipolar braiding statistics} is made in terms of emergent, rank-1 vector potentials that are built out of the underlying rank-2 gauge fields. Pertinent field theories of the quasiparticle dynamics in the R2TC are developed, and the accompanying conservation laws derived. A {\it dipolar BF theory} of the rank-2 gauge fields is constructed and shown to correctly capture the dipolar braiding statistics, in contrast to the conventional BF theory capturing the monopolar braiding statistics of anyons in the rank-1 toric code.

Ammonium-based ionic liquids: synthesis, characterization, computational approach, molecular docking study and phytotoxicity assessment

Ionic liquids, without any doubt, have emerged as a focus of interest for general chemistry due to a few exceptional and environmentally friendly properties. In this report we synthesized ammonium based novel ionic liquids via Bronsted proton doner method using an identical cation as N-Methyl-diethanolamine along with distinctive anions as 2-Chlorobenzoic Acid and 2-Methylbenzoic Acid and characterized by FT-IR and 1H-NMR spectroscopy. Theoretical simulation was carried out by using Gaussian-09 software for predicting molecular properties as total energy, electrostatic energy, dipole moment, ionic length, electrostatic potential, thermochemistry and energies for HOMO and LUMO by generating optimized structures of the compounds. The crystal structure of the human serum albumin (PDB ID:1AO6) was used to study the interaction of HSA with the ILs and their binding affinities. The final compounds that studied here could bind near the Asp108, Arg145, Tyr148 residues of the HSA. Phytotoxicity evaluation work is executed for monocotyledonous seeds (Oryza Sativa) in six distinct concentrations (0, 25, 50, 100, 200, 400 mmol/L) and lowest and highest inhibitory impact on germination percentage and root length is determined which were found 100% and 1.50 cm in 25 mmol/L and 0% and 1.48 cm in 400 mmol/L respectively with ±SD. In this research, experimental, theoretical properties and the in vitro toxicity level of the synthesized ILs were observed.

Adsorption of the Xanthan Gum Polymer and Sodium Dodecylbenzenesulfonate Surfactant in Sandstone Reservoirs: Experimental and Density Function Theory Studies.

Chemical flooding using a polymer and/or surfactant has been widely applied in oilfields worldwide for enhanced oil recovery. Chemical adsorption in reservoirs has a significant effect on the rock permeability and wettability and hence can affect the overall oil production. In this work, two chemicals, namely, the xanthan gum (XG) biopolymer and sodium dodecylbenzenesulfonate (SDBS) anionic surfactant, were used individually as displacement fluids. The amount of chemical adsorption on the rock surface and the residual resistance factor (permeability reduction) were calculated throughout the flooding experiments using an unconsolidated sandstone (SS) pack model. The effects of the injected chemicals’ concentration and reservoir salinity on adsorption capacity have been examined. Additionally, the effect of the addition of nanosilica particles (NSPs) to the injected fluid on the rock adsorption was also investigated. The results showed that the amount of XG and SDBS adsorption on the rock surface increased, albeit to a different extent, by increasing the chemical concentration at the applied salinities (0, 3.5, 5, and 10%) of the displacement fluids. Also, the permeability reduction increased with the increase in XG and SDBS concentrations; however, permeability reduction due to SDBS flooding was lower than that of XG in SS. The use of NSPs as a coinjectant to the XG and SDBS displacement fluids increased the adsorption on the SS rock. A plausible mechanism for the adsorption of the XG/NSP and SDBS/NSP blends on the SS surface was proposed. A density function theory calculation was employed to establish a relation between the adsorptivity of NSPs on SDBS and XG and the total energy and dipole moment of the molecules.

Synthesis and spectroscopic characterization of nicotinaldehyde based derivatives: SC-XRD, linear and non-linear optical studies

In this study, new arylated derivatives of pyridine named as 6-(4-tertbutylphenyl)-nicotinaldehyde (TBPNA) and 6-(4-hydroxyphenyl)-nicotinaldehyde (HPNA) were synthesized by Suzuki Miyaura CC coupling approach. The structures of newly synthesized compounds were authenticated by spectroscopic techniques like FT-IR, UV-Vis, and 1H-NMR. Furthermore, the structural features of TBPNA and HPNA were explored by using the single-crystal X-ray diffraction technique (SC-XRD) showing monoclinic crystal structure and P21/c space group for both compounds. For a comprehensive study of the compounds, a computational quantum chemical study is also performed by using the density functional theory (DFT). The said compounds were optimized using the B3LYP method and a 6-311++G(d, p) basis set. The comparison of theoretical (DFT) and experimental (SC-XRD) data on structural parameters displayed good agreement. Frontier molecular orbital (FMO), natural bond orbital (NBO), the molecular electrostatic potential (MEP), and time-dependent density functional theory (TD-DFT) were also performed at the B3LYP/6-311++G(d,p) level of theory to get complete insights into electronic communications, intramolecular charge transfer (ICT) process, electronic transition and oscillation strength. The optoelectronic and non-linear optical (NLO) responses of the synthesized compounds were determined by computing the total dipole moment (μtot), average polarizability ⟨α⟩, and the first hyperpolarizability (βtot) at different functional(s) such as HF, M06, M062X, CAM-B3LYP, LC-BLYP, and B3LYP, paired with the 6-311++G(d,p) basis set. The B3LYP method exhibited the highest values of ⟨α⟩ and (βtot) for HPNA and TBPNA, which were found to be many times higher than the value of urea (⟨α⟩ = 34.055 a.u., βtot =90.527 a.u.), used as a standard NLO material.

Geometric and Electronic Investigations of 2,7-bis((3-(pyridin-2-yl)-1H-pyrazol-1-yl) methyl) naphthalene Using Computational Chemistry

Understanding geometric and electronic characterizations of organic molecules that working as flexible ligands; may helpful to predict their chemical behavior either in solution or solid state when reacted with metal ions. We have investigated bis-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)) ligands using computational chemistry. Disubstitutions in position 2,7-naphthyl based ligand; as linker between bis(3-(pyridin-2-yl)-1H-pyrazol-1-yl)) units is our molecule of investigation. HyperChem (V.8) software, semi-empirical, AM1 were used as methods of calculations. Some thermo-physical properties have been calculated such as total energy, dipole moment, binding energy and heat of formation. The calculated total energy was recorded at118141.72-2 kcal/mol. The molecule is slightly polar as the dipole moment observed at 0.895D. The energy gap (Egap) between HOMO and LUMO; as one of the most important parameter for molecular stability recorded at 8.29 eV. Moreover, ionization potential (I), electronic affinity (A), global hardness (η), electronegativity (χ), electronic chemical potential (μ), electrophilicity (ω) and chemical softness (Ѕ) were calculated. As HOMO and LUMO energy is responsible for molecular reactivity. So, the calculated parameters of molecule may helpful to understanding its chemical behavior. Geometrically, comparison between the single X-ray crystallography and calculated data such as; bond angles and bond lengths were done. The calculated data approximately agreed with the single X-ray crystallography reported data[1].

Emergent tracer dynamics in constrained quantum systems

We show how the tracer motion of tagged, distinguishable particles can effectively describe transport in various homogeneous quantum many-body systems with constraints. We consider systems of spinful particles on a one-dimensional lattice subjected to constrained spin interactions, such that some or even all multipole moments of the effective spin pattern formed by the particles are conserved. On the one hand, when all moments - and thus the entire spin pattern - are conserved, dynamical spin correlations reduce to tracer motion identically, generically yielding a subdiffusive dynamical exponent $z=4$. This provides a common framework to understand the dynamics of several constrained lattice models, including models with XNOR or $tJ_z$ - constraints. We consider random unitary circuit dynamics with such a conserved spin pattern and use the tracer picture to obtain exact expressions for their late-time dynamical correlations. Our results can also be extended to integrable quantum many-body systems that feature a conserved spin pattern but whose dynamics is insensitive to the pattern, which includes for example the folded XXZ spin chain. On the other hand, when only a finite number of moments of the pattern are conserved, the dynamics is described by a convolution of the internal hydrodynamics of the spin pattern with a tracer distribution function. As a consequence, we find that the tracer universality is robust in generic systems if at least the quadrupole moment of the pattern remains conserved. In cases where only total magnetization and dipole moment of the pattern are constant, we uncover an intriguing coexistence of two processes with equal dynamical exponent but different scaling functions, which we relate to phase coexistence at a first order transition.

Study on spectral properties and active sites of glucose and fructose based on density functional theory

• Based on density functional theory and time-dependent density functional theory, we systematically studied the infrared spectra, ultraviolet spectra, electron hole, active sites and total transition dipole moments of glucose and fructose molecules • The optical rotation properties of glucose and fructose are explained in detail. • The theoretical study on the molecular structure and properties of glucose and fructose is of great significance for drug research and development, the preparation of biofuels and the protection of related metals. Glucose and fructose are closely related to people's life and production. Based on density functional theory, the B3LYP/6-311++G(d, p) and B3LYP/6-311 + G(d, p) levels of theory are adopted to optimize the structure and calculate the frequency of glucose and fructose molecules by adding B3LYP-D3(BJ) dispersion correction in this paper. The first 50 excited states of glucose and fructose molecules are calculated in SMD solvent model by using time-dependent density functional theory and B3LYP / def2-TZVP level of theory. It is verified that the selected method and basis set are reasonable by comparing the theoretical spectrum with the experimental spectrum. It is found that the plane structure of glucose molecule is more distorted than that of fructose molecule. The stretching vibration of C O bond of fructose is more intense than that of glucose. The absorption peak of fructose at 209.70 nm is characterized by n → σ* transition and is in the tail absorption band, other absorption peaks are all in the far ultraviolet absorption band, and it shows the transition characteristics of σ → σ*. According to the electron-hole analysis, the excitation of the 27th, 34th, 36th and 46th excited states belongs to local excitation, the excitation of the 29th excited state belongs to Rydberg excitation, and the other excited states belong to charge transfer excitation. The optical rotation mechanism of sugar molecules is explained by the direction of the transition dipole moment. O16 of glucose and O24 of fructose were electrophilic site respectively. The active product is 5-hydroxyethyl furfural (5-HMF) by oxidation of 5-hydroxymoms. This study could provide a theoretical basis for drug development, biofuel preparation and metal protection.

Design, Synthesis, DFT, TD-DFT/PCM Calculations, and Molecular Docking Studies on the Anti-COVID-19, and Anti-SARS Activities of Some New Bis-Thiazoles and Bis-Thiadiazole

A novel synthesis of bis(thiazoles) and bis(thiadiazole), each connected to a thienothiophene moiety, is described. The DFT calculations support the favored synthesis of one of the anticipated bis(thiazole) regioisomers. The B3LYP/6-311G** level of theory was used to optimize quantum mechanical calculations of geometrical characteristics and energy of new compounds under study. The electronic absorption of the new compounds in ethanol solvent was handled and finished using time-dependent-density functional theory (TD-DFT) at the B3LYP/6-31G(d,p) level with the addition of the polarizable continuum solvation technique TD-DFT/PCM. The permissible singlet transitions are identified, and their involvements in the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) are described. Natural bond orbital (NBO) analysis was used to investigate hyper conjugative partnerships, molecular stability, and bond strength. Mean polarizability, total static dipole moment, anisotropy of polarizability, and mean first-order hyperpolarizability have all been computed. The results reveal that the compounds are promising contenders for non-linear optical materials. The molecular docking mechanism between ligands 8a–8c and COVID-19/5epw or SARS/5wrg receptors was done to explore the binding modes of these compounds at the active sites. Molecular docking results have shown that the compounds 8a–8c can be considered as a potential agent against COVID-19/5epw and SARS/5wrg receptors.

Density Functional Theory Study of the Structural, Electronic, Non-Linear Optical and Thermodynamic Properties of Poly (3-Hexylthiophene-2, 5 - Diyl) in Gas Phase and in Some Solvents

Poly(3-hexylthiophene-2,5-diyl) (P3HT) and its derivatives are polymer based materials with π conjugation framework. P3HT is useful photoelectric material and can be used in organic semiconductor devices such as PLED, OLED, Nonlinear optical devices and solar cells. In this work, a theoretical study of P3HT in the gas phase and in some solvents (methanol, thiophene, chloroform, toluene, and acetone) were investigated and reported based on Density Functional Theory (DFT) as implemented in Gaussian 09 package using B3LYP/6-31++G (d, p) basis set. Structural properties such as bond lengths and bond angles as well as the HUMO, LUMO, energy gap, global chemical index, thermodynamic properties, NLO and DOS of the P3HT molecule in order to determine the reactivity and stability of the molecule were obtained. The results obtained showed that the solvents have effects on the structural, electronic and non-linear-optical properties of the molecule. The optimized bond length revealed that the molecule has a stronger bond in methanol with smallest bond length of about 1.0840Å (C28-H35) than in gas phase and the rest of the solvents. It was observed that the molecule is more stable in methanol with HOMO-LUMO energy gap and chemical hardness of 3.8338eV and 1.9169eV respectively. This indicates that the energy gap and chemical hardness of P3HT molecule increase with the increase in polarity and dielectric constants of the solvents. The energy gap obtained is compared with the one in literature \((3.10 \mathrm{eV})\). This indicates that the reported energy-gap leads by about \(0.7 \mathrm{eV}\). The calculations of thermodynamic properties indicate that P3HT molecule has the highest value of specific heat capacity \((\mathrm{CV})\), that is \(152.307 \mathrm{Cv}(\mathrm{Kcal} / \mathrm{Mol})\) in methanol, toluene has the highest value of entropy as \(266.960\) (Kcal/Mol), and thiophene has the highest value of zero-point vibrational energy (ZPVE) as \(455.37486 \mathrm{Kcal} / \mathrm{Mol}\). The NLO properties show that methanol has the highest value of total dipole moment ( \(\mu_{\text {tat }}\) ) as \(1.01764\) a u while acetone has the highest value of first order hyperpolarizability ( ( tot) as \(4.4447 \times 10^{-30}\) esu than the rest of the solvents. The values obtained for the first order hyperpolarizability for P3HT in acetone is about 12 times than that of the urea molecule, \(\left(0.3728 \times 10^{-30} \mathrm{esu}\right)\) which is commonly used for the comparison of NLO properties The results of the \(I R\) spectra show that the studied molecule was stable in both the gas phase and in solvents since no imaginary frequency was observed. It was also observed that the most intense frequency was found to be \(3024.9421 \mathrm{~cm}^{-1}\) at an intensity of \(140.2464 \mathrm{~km} / \mathrm{mol}\) in methanol and \(3088.6908\) \(\mathrm{cm}^{-1} at intensity of 77.6119 \mathrm{~km} / \mathrm{mol}\) in gas phase. The theoretical values of the open circuit voltage were found to be \(1.635 \mathrm{eV}, 1.614 \mathrm{eV}, 1.605 \mathrm{eV}, 1.576 \mathrm{eV}, 1514 \mathrm{eV}\), and \(1.445 \mathrm{eV}\) for methanol, toluene, acetone, chloroform, thiophene and the gas phase respectively. These changes in the properties of the molecule are observed due to the differences in the dielectric constants of the solvents. The results show that careful selection of the solvents can enhance the properties of the molecule for Organic solar cells (OSC)s applications.

Dipolar Bose-Hubbard model

We study a simple model of interacting bosons on a d-dimensional cubic lattice whose dynamics conserves both total boson number and total boson dipole moment. This model provides a simple framework in which several remarkable consequences of dipole conservation can be explored. As a function of chemical potential and hopping strength, the model can be tuned between gapped Mott insulating phases and various types of gapless condensates. The condensed phase realized at large hopping strengths, which we dub a Bose-Einstein insulator, is particularly interesting: despite having a Bose condensate, it is insulating, and despite being an insulator, it is compressible.

Modeling the electronic properties for CNT interacted with ZnO, CuO, and Co3O4

Because of the wide applications of carbon nanotubes (CNTs) and magic properties of metal oxides, Hartree–Fock quantum mechanical calculations at HF/STO-3G were applied to study the electronic properties of CNTs and their interaction with ZnO, CuO, and Co3O4. Calculations were conducted to calculate HOMO/LUMO bandgap energy ∆E, molecular electrostatic potential (MESP), and total dipole moment (TDM) for CNTs, CNT-Zn-O, CNT-Cu-O, CNT-Co-O, and CNT-O-Zn, CNT-O-Cu, CNT-O-Co following the two mechanisms of interaction as adsorbed and complex state. The calculations show that the interaction of CNTs with metal oxides increases its reactivity where MESP indicated to more distribution charges and an increase in the TDM value after the interaction of CNTs with metal oxides. Where the interaction of CNT-Co-O as adsorbed state has the highest TDM with the lowest bandgap ∆E which confirms that CNT-Co3O4 can be used in sensing devices.

Spotlight on Charge-Transfer Excitons in Crystalline Textured n-Alkyl Anilino Squaraine Thin Films

Prototypical n-alkyl terminated anilino squaraines for photovoltaic applications show characteristic double-hump absorption features peaking in the green and deep-red spectral range. These signatures result from coupling of an intramolecular Frenkel exciton and an intermolecular charge transfer exciton. Crystalline, textured thin films suitable for polarized spectro-microscopy have been obtained for compounds with n-hexyl (nHSQ) and n-octyl (nOSQ) terminal alkyl chains. The here released triclinic crystal structure of nOSQ is similar to the known nHSQ crystal structure. Consequently, crystallites from both compounds show equal pronounced linear dichroism with two distinct polarization directions. The difference in polarization angle between the two absorbance maxima cannot be derived by spatial considerations from the crystal structure alone but requires theoretical modeling. Using an essential state model, the observed polarization behavior was discovered to depend on the relative contributions of the intramolecular Frenkel exciton and the intermolecular charge transfer exciton to the total transition dipole moment. For both nHSQ and nOSQ, the contribution of the charge transfer exciton to the total transition dipole moment was found to be small compared to the intramolecular Frenkel exciton. Therefore, the net transition dipole moment is largely determined by the intramolecular component resulting in a relatively small mutual difference between the polarization angles. Ultimately, the molecular alignment within the micro-textured crystallites can be deduced and, with that, the excited state transitions can be spotted.

DFT, hirshfeld and molecular docking studies of a hybrid compound - 2,4-Diamino-6-methyl-1,3,5-triazin-1-ium hydrogen oxalate as a promising anti -breast cancer agent

The six-membered heterocyclic ring - 1,3,5-triazine and its derivatives have garnered a lot of attention because they're good bioactive herbicides, cancer agents, and other things. One such triazine derivative, 2,4-diamino-6-methyl-1,3,5-triazin-1-ium hydrogen oxalate (DMTHO), was produced in this work, and the structure was optimised using density functional theory's B3LYP functional and the basis set 6–31++G (d,p). Additionally, the chemical underwent in-depth research using molecular docking analysis, Hirshfeld, and density functional theory. The electron densities distribution in the atoms is provided by natural orbital analysis, which also characterises the chemical bonding and reaction behaviour of the compound. The calculated HOMO and LUMO energies indicate that charge transfer occurs inside the molecule. Chemical reactivity traits including HOMO-LUMO energy gaps, softness, total energy, chemical hardness, electronic chemical potential, and electrophilicity of bioactive substances have all been subjected to analytical investigation. Total dipole moment (μ) and first-order hyperpolarizability (β) measurements for the investigated chemical indicate that DMTHO may exhibit microscopic nonlinear optical (NLO) behaviour with nonzero values. A quantitative description about intermolecular interactions in the produced crystal is provided by the Hirshfeld surface analysis. Further docking studies of the compound have been performed and the results reveals that the compound inhibit the breast cancer related protein - casein kinase (CK2) – and the possibility of developing as a potential anti breast cancer lead.

Co(II), Cu(II) and Zn(II) complexes of tridentate ONO donor Schiff base ligand: A DFT studies

A series of Cu(II), Co(II), and Zn(II), mononuclear Schiff base complexes were studied and characterized by DFT calculations. The ligand was derived from the experiment of condensing 5-acetyl-4-hydroxy-2H-1,3-thiazine-2,6(3H)-dione with o-phenylenediamine. The Schiff base ligand has coordination sites on phenolic oxygen, azomethine nitrogen, and amino group nitrogen, where it behaves as a monobasic tridentate. All studied structure was constructed based on the ration 1:1 (metal: ligand) stoichiometry. Except for the Cu(II) complex, which exhibited a square planar arrangement, the metal complexes exhibited octahedral geometry. The Orca quantum program's Density Function Theory (DFT) level was used to optimize the structure and several structural parameters of the ligand and its metal complexes, including total energy, HOMO, LUMO, and dipole moment. Correlations were established between the calculated and experimental data.

Computational Evidence for the Crucial Role of Dipole Cross-Correlations in Polar Glass-Forming Liquids.

In this Letter, we analyze the dipole-dipole correlations obtained from the molecular dynamics simulations for strongly and weakly polar model liquids. As a result, we find that the cross-correlations' contribution to the system's total dipole moment correlation function, which is directly measured in the dielectric spectroscopy experiment, is negligible for weakly polar liquids. In contrast, the cross-correlations' term dominates over the self-correlations' term for the examined strongly polar liquid. Consequently, our studies strongly support the interpretation of the dielectric spectra nature of glass-forming liquids recently proposed by Pabst etal.

Plasmon-induced excitation energy transfer in silver nanoparticle dimers: A real-time TDDFTB investigation.

Using real-time quantum dynamics calculations, we perform theoretical investigations of light-induced interactions and electronic excitation transfer in a silver nanoparticle dimer. Real-time time-dependent density functional tight-binding (RT-TDDFTB) calculations provide details of the quantum dynamical processes at an electronic/atomistic level with attosecond resolution. The computational efficiency of RT-TDDFTB allows us to examine electronic dynamics up to picosecond time scales. With time scales varying over six orders of magnitude, we provide insight into interactions between the nanoparticle and laser and between nanoparticles. Our results show that the coupling between nanoparticle monomers is dependent on the separation distance between the nanoparticles in the dimer. As the interparticle distance is varied, the dipole-dipole interactions and electronic excitation transfer mechanisms are markedly different. At large distances (from 50 to 20 Å), the energy transfer from NP1 to NP2 becomes more efficient as the interparticle distance decreases. The total dipole moment of the Ag14 nanoparticle dimer increases linearly at an interparticle distance of 20 Å and reaches its maximum after 1.2ps. The electronic excitation transfer is also the most efficient at 20 Å. At short distances, back-transfer effects reduce the ability of the dimer and NP1 to accept energy from the incident electric field. We attribute the distance-dependent features of the nanoparticle dimer to the beating between the laser acting on NP1 and the back transfer from NP2 to NP1.

High energy storage density and efficiency achieved in dielectric films functionalized with strong electronegative asymmetric halogen-phenyl groups

Capacitor dielectric films exhibiting high energy storage density and efficiency within a wide operating temperature range are crucial for advancing electrical and electronic devices. The low energy storage density and working temperature as well as the high manufacturing costs of the state-of-the-art BOPP films limit their use as an energy storage unit for developing smart grids or the internet of things, while most of the polymer-based dielectric films reported currently are facing the issues of the rapid efficiency deterioration with the increasing of temperature. In this work, the high energy storage density and efficiency are achieved in the low-cost flexible epoxy films innovatively modified by trifluoro-phenyl group functionalization. Introducing strongly electronegative fluorinated phenyl groups greatly improves the energy storage density due to the increase of the total molecular dipole moment of the polymer film. Meanwhile, achieving the high energy storage efficiency is accomplished via gradually increasing the charge trapping site density of epoxy resins functionalized with different densities of fluorinated phenyl groups, which can be demonstrated through both thermally stimulated current (TSC) spectroscopy and the first-principles calculations results. Finally, it is experimentally demonstrated that deeper charge traps can be obtained in slightly crosslinked trifluoro-phenyl functionalized epoxy films, resulting in an energy storage density of 3.31 J/cm3 and a high energy storage efficiency of 95% at 100 °C.

Structure Characterization, Spectroscopic investigation and Nonlinear Optical Study using Density Functional Theory of (E)-1-(4-Chlorophenyl)-3-(4-methylphenyl) prop-2-en-1-one

The structural confirmation of the (E)-1-(4-Chlorophenyl)-3-(4-methylphenyl)prop-2-en-1-one compound is done by experimental techniques. Experimental techniques FTIR, proton NMR, UV-Visible, performed for the compound. The experimentally obtained results are compared with theoretically (density functional theory) obtained results. The decomposition and melting point of the compound is obtained by TGA and DTA. Density functional theory is performed for the (E)-1-(4-Chlorophenyl)-3-(4-methylphenyl)prop-2-en-1-one compound B3LYP/6-311G++(d,p) basis set. Time dependent density functional theory calculated for three different methods B3LYP, Hartree-Fock and CAMB3LYP also employed for the MLCC at 6-311G++(d,p) basis set. The MLCC compound is having the total dipole moment 4.45 D. The static (ω=0.0) mean polarizability 17.40 x10-24 esu, anisotropic polarizability 23.37 x10-24esu, first hyperpolarizability 11.84 x10-30 esu, second hyperpolarizability 11.88x10-36 esu. Dynamic mean polarizability (ω=0.0569, ω= 0.04282) 17.84 x 10-24esu, 17.65x10-24esu. Dynamic anisotropic polarizability (ω=0.0569, ω= 0.04282) 24.26 x 10-24esu, 23.86 x10-24esu. Dynamic first hyperpolarizability (ω=0.0569, ω= 0.04282) 18.60 x 10-30 esu, 15.06 x10-30 esu. Dynamic second hyperpolarizability (ω=0.0569, ω= 0.04282) 35.37x10-36 esu, 20.0x10-36 esu.