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Compared with antiferroelectric (AFE) orthorhombic R phases, AFE orthorhombic P phases in NaNbO3 (NN) ceramics have been rarely investigated, particularly in the field of energy-storage capacitors. The main bottleneck is closely related to the contradiction between difficultly-achieved stable relaxor AFE P phase and easily induced P-R phase transition during modifying chemical compositions. Herein, we report a novel lead-free AFE ceramic of (1-x)NN-x(Bi0.5K0.5)ZrO3 ((1-x)NN-xBKZ) with a pure AFE P phase structure, which exhibits excellent energy-storage characteristics, such as an ultrahigh recoverable energy density (Wrec) ∼4.4 J/cm3 at x = 0.11, a large powder density PD ∼104 MW/cm3 and a fast discharge rate t0.9 ∼45 ns. The analysis of polarization-field response, Raman spectrum and transmission electron microscopy demonstrates that the giant amplification of Wrec by ≥177% should be mainly ascribed to the simultaneously and effectively enhanced AFE P-phase stability and its relaxor characteristics, resulting in a diffused reversible electric field-induced AFE P-ferroelectric phase transition with concurrently increased driving electric fields. Different from most (1-x)NN-xABO3 systems, it was found that the reduced polarizability of B-site cations dominates the enhanced AFE P-phase stability in (1-x)NN-xBKZ ceramics, but the almost unchanged tolerance factor tends to cause the AFE R phase to be induced at a relatively high x value.

Ce2[Zr1-x(Zn1/3Nb2/3)x]3(MoO4)9 (CZ1-x(ZN)xM) (x = 0.02–0.08) compounds were successfully prepared to scientifically examine the effect of (Zn1/3Nb2/3)4+ doping on phase composition, microstructures, and properties. The XRD results showed that all compounds formed a pure phase with the space group of R-3c. SEM results indicated that all compounds were compact at 675 °C, and the lattice parameters and average grain size decreased with doping. Performance analysis illustrated that er was closely related to the polarizability, and Q∙f was affected by the lattice energy of the Mo–O bond. The τf was maintained at an excellent level. Far-infrared analysis indicated that the major dielectric contribution to CZ1-x(ZN)xM ceramics was related to the absorption of phonon oscillation. The optimum properties (er = 10.72, Q∙f = 59,381 GHz, τf = −11.48 ppm/°C) were obtained when x = 0.04.

Hypothesis The presence of nanoparticles at oil-water interface influences the interaction forces between Pickering emulsions. When charged nanoparticles are at the oil-water interface of an electrostatically stabilized emulsion, in addition to the screened Coulombic interaction, electric dipolar force also influences the total inter-droplet force profiles. An in-depth understanding of the effects of such electric dipolar forces is essential for designing colloidally stable Pickering nanoemulsions for various applications. Experiments Inter-droplet forces between γ-Al2O3 nanoparticle stabilized oil-in-water nanoemulsion, containing superparamagnetic nanoparticles (magnetically polarizable) in the oil phase, are measured using the magnetic-chaining technique at different pH and salt concentrations. The role of mono-, di- and tri-valent salts on the inter-droplet force profiles are assessed. Findings Force measurement studies reveal a lowering of inter-droplet spacing, within the linear chains, for higher salt concentrations due to an increased screening. Strong interfacial attachment of the charged nanoparticles results in the formation of an asymmetric charge cloud leading to an electric dipolar interaction. Incorporating the contributions of electric dipolar and screened Coulombic interactions, the theoretically estimated total repulsive force magnitudes are in good agreement with the experimental data. The obtained results offer better insights into the nature of colloidal force between charged particle stabilized nanoemulsions.

Density functional theory (DFT) has become a powerful tool in the investigation of the molecular structure and vibrational spectrum of the compound. Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of the title compound were recorded experimental and theoretical study has been done by quantum computational calculations of DFT using Gaussian software package. The structural, vibrational and electronic properties of the title compound were presented using the B3LYP method with 6-311++G(d,p) basis set. The geometry of the title compound was optimized. The experimental vibrational spectra were compared with the calculated spectra and each wave number was assigned on the basis of potential energy distribution (PED). Molecular electrostatic potential for the title compound was calculated to predict the reactive sites for electrophilic and nucleophilic attack. Energy band gap of 3.62 eV was calculated from HOMO-LUMO energies and the charge transfer within the molecules was confirmed. The linear polarizability (α) and the first order hyperpolarizability (β) values of the investigated molecule have been calculated and the title compound exhibits NLO property. The biological activity has been confirmed theoretically for the treatment of lung cancer.

In the present research, structural representation, phase transition, and dielectric characteristics of Ta5+ ionic substituted Co0.5Ti0.5(Nb1-xTax)O4 (x = 0–1) ceramics were thoroughly investigated. Combined with the changes of diffraction peaks in the X-ray diffraction spectra, such as (002) and (101) crystalline planes near 20°, and the evolutionary trend of the strongest peak in the Raman spectra, a phase transition from rutile to trirutile structure at x = 0.6 was confirmed, suggesting the emergence of structural evolution. Thus, the structural evolution showed a significant impact on the dielectric characteristics, as evidenced by the weakening of the dielectric polarizability with the increasing amount of Ta5+ ion, which led to a reduction in the dielectric constant; the dielectric loss is also closely related to the packing fraction (PF) arising from the structural changes. Additionally, infrared and THz time-domain spectroscopy revealed that the dielectric losses in the microwave band were originated from the oscillatory absorption of structural phonons and supported that the effects of structural evolution on the intrinsic dielectric properties due to the introduction of Ta5+ ion.

Theoretical and experimental investigations on the molecular structure of 2-amino-5-chloro-3-nitropyridine (2A5Cl3NP) are presented. The molecular equilibrium geometry of the title molecule is fully optimized. Quantum chemical calculations of the HOMO-LUMO energies, energy gap (ΔE), electron negativity (χ), and chemical potential (μ), global hardness (ƞ), and global softness (S) are calculated for the title molecule. The title compound has a low softness value (0.2770) and the calculated value of electrophilicity index (7.7250) describes the biological activity. The stability and charge delocalization of the title molecule are studied by Natural Bond Orbital Analysis (NBO), Non-Linear Optical (NLO) behaviour in terms of first order hyperpolarizability, dipole moment, anisotropy of polarizability are accounted. The computed values of dipole moment (μ) for 2A5Cl3NP molecule is 3.0173 Debye, polarizability (α) is 1.6017 × 10–23esu, hyperpolarizability (β) is 5.08173 × 10–30esu. The high β value and non-zero value of μ indicate that the title compound might be a good candidate for NLO material. The strength of the interaction between electron donors and electron acceptors is measured by the magnitude of energy of hyper conjugative interactions E (2). The second-order Fock matrix is calculated to study the donor–acceptor interactions in NBO analysis.

Optically transparent L-Proline Adipate (LPA) single crystal has synthesis by slow evaporation solution growth technique (SEST) method at ambient condition. The crystallinity of LPA crystal was examined by powder XRD analysis, which crystallizes in the monoclinic system. The various functional groups were identified by FTIR spectra and it compares with a simulated spectrum of LPA by using DFT/B3LYP 6–311++G(d,p) set. The Photoluminence spectrum (PL) was used to determine the optical properties of LPA. The Vickers microhardness measurements reveal the crystal possesses soft category of mechanical strength. The determined HOMO-LUMO value shows the crystal is chemically active and charge transfer occurs within the molecule. The linear polarizability (α) and 1st order hyperpolarizability (β) values of LPA have been investigated.

Organic nonlinear optical single crystal of L-Isoleucine D-Valine (LIDV) with dimensions 3 X 3 X 4 mm3 was successfully grown by the slow evaporation solution growth technique (SEST). The structural analysis of the grown crystals has been analyzed by Powder X-ray diffraction which revealed that grown (LIDV) crystal belongs to monoclinic crystal system with P21 space group. The structure of LIDV is optimized using Density Functional Theory (DFT) method. The vibrational band assignments were performed at B3LYP/6-31G + (d, p) theory level. The theoretical IR frequencies are found to be in good agreement with the experimental IR frequencies. Nonlinear optical (NLO) behavior of LIDV is examined by the theoretically predicted values of first hyper polarizability. The cut-off wavelength and the optical band gap value of the grown crystal is found using Optical studies. The SHG efficiency of the grown material is found to be 2.5 times the reference material.

In this study, a sequence of side chain liquids dependent on polysiloxane crystals was investigated. In this study, the molecular weight of polymers is being investigated in a systematic manner, using one molecule's weight with added ratios of five. The backbone is made up of units with low polarizability, and the optical signal is particularly responsive to the former but not to the latter of the LF GeO2 nanoparticles. As a result of the matrix construction for a polymer with liquid crystals with a side chain, the polymer evaporates, unless changes in chain orientation are fully coupled via the mesogenic side chains. The condition of orientational order in these polymers is assessed using infrared spectroscopy, which is combined with the threshold voltage result to validate the hypothesis and investigate the effect of Germania nanoparticles on the orientational order parameter. (S), Switching voltage and reaction times. Produce electro-optic cells of varying thicknesses and investigate the effect on optical response times.

Substitution of Ga3+ by [Zn0.5Ti0.5]3+ in MgGa2O4 improved the comprehensive properties of the resultant spinel. A continuous solid solution with a spinel structure was formed in Mg(Zn0.5Ti0.5)2xGa(2−2x)O4 (0 ≤ x ≤ 1); here, Zn2+ occupied the tetrahedral 8a site while Ti4+ occupied the octahedral 16d site, resulting in a decrease in the degree of inversion λ from 0.86 to 0. The optimal sintering temperature decreased from 1460 °C to 1220 °C, and the dielectric constant (er) increased from 8.8 to 14.9; these changes could be ascribed to the greater polarizability of [Zn0.5Ti0.5]3+ relative to that of Ga3+. The temperature coefficient of resonant frequency (τf) of the material remarkably increased from −64.1 ppm/°C to −16.8 ppm/°C, which may be attributed to the increase in dielectric polarizability/molecular volume, bond energy, and bond valence in B-sites. The high-quality factor (Q × f) slightly decreased from 89,253 GHz to 73,432 GHz with decreasing λ and packing fraction. Optimal microwave dielectric properties were obtained from the sample with x = 1 and sample sintered at 1220 °C; in this case, er = 14.9, Q × f = 73,432 GHz, and τf = −16.8 ppm/°C.

The τf of Y3Ga5O12 ceramics was adjusted by Ca2+/Ti4+ co-doping for Y3+ at A-site and Ga3+ at C-site to form CaxY3-xTixGa5-xO12 (0 ≤ x ≤ 2.0) ceramics by the solid-state reaction. When 0 ≤ x ≤ 1.7, all the samples remained as single garnet-structured with Ia-3d space group. The er increased from 10.4 ± 0.1 to 15.9 ± 0.1, and τf optimized from −54.7 ± 1.0 to −8.3 ± 1.0 ppm/℃, attributing to the increase in polarizability per volume and “rattling” effect. Meanwhile, the Q × f slightly decreased from 98,200 ± 500 GHz to 65,300 ± 500 GHz due to the decrease in packing fraction. As x increased to 2.0, the properties dramatically deteriorated owing to the second phase CaTiO3. Optimal properties were obtained at x = 1.7, with er = 15.9 ± 0.1, Q × f = 65,300 ± 500 GHz and τf = −8.3 ± 1.0 ppm/℃.

Summary Piezoelectricity in ferroelectric polymers originates from the electrostrictive effect coupled with a remanent polarization. However, its structural origin remains controversial, and it is not clear how modifying the electrostriction can further improve piezoelectricity for polymers. Here, we report that electrostriction can be significantly enhanced in poled poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] random copolymers containing extended-chain primary crystals and relaxor-like secondary crystals in the oriented amorphous fraction (SCOAF). As a result of the high polarizability of dipoles and ferroelectric nanodomains in the SCOAF, the inverse piezoelectric coefficient d31 reaches as high as 77 ± 5 pm/V for the P(VDF-TrFE) 55/45 copolymer at 55°C. This finding not only extends our understanding of piezoelectricity in polymers but also provides guidance for further enhancing the piezoelectricity of ferroelectric polymers in the future.

B-site deficient eight-layer hexagonal perovskites possess in general high quality factors and large positive temperature coefficients of resonant frequency (τf). Recently we successfully lowered τf of shifted perovskite Ba8CoNb6O24 down to near zero through one-third Ta5+ substitution but raised the cost of the materials. In this work, Ba8CoNb6O24 was doped with cheaper elements Sb5+ on Nb5+ sites using conventional solid-state reactions, and near-zero τf of 0.66(2) ppm/°C, modest er of 27.99(3), Q × f of 1.016(6) × 104 GHz, and significantly reduced cost of the ceramics were achieved on the composition Ba8CoNb5.4Sb0.6O24. The lower polarizability of Sb5+ than Nb5+ results in smaller er and therefore τf values. About 15 % Sb5+ substitution for Nb5+ in Ba8CoNb6-xSbxO24 dramatically transforms the shifted structure to twinned structure, in contrast with 50 % Ta5+ substitution in the Ta5+ case. This is ascribed to reduced SOJT effects and ionic size of d10 Sb5+ compared with d° Nb5+ and Ta5+.

KxNa0.5-xBi4.46Ce0·04Ti4O15+y (x = 0, 0.04, 0.08, 0.12, 0.16, 0.20) ceramics were synthesized by solid state reaction. The microstructure and electrical properties of the solid solutions were characterized. It is found that the doping of appropriate amount of K improved the degree of lattice distortion of the material, and the characteristic parameter b/a of lattice distortion obtained the maximum value through structural refinement at x = 0.12. A defect dipole pair ( K B i ″ − V o • • ) is formed by adjusting the defects of the material. The polarizability of defects is 4.88 × 10-37F·m2. The formation of defect dipole pairs that deflect towards the direction of spontaneous polarization reduces the difficulty of polarization and improves the piezoelectric properties. Finally, the optimal piezoelectric coefficient (d33) of NBCT-xK ceramics is 23 pC/N, and the residual polarizability (2Pr) is 4.14 μC/cm2. The values of residual polarization rate (2Pr), piezoelectric coefficient (d33) and b/a show the same trend, which will gradually decrease when their value increases to a certain extent. The dielectric loss of all samples below 200 °C are lower than 0.01, and the dielectric constant is relatively flat below 400 °C. Moreover, the Curie temperature (Tc) of KxNa0.5-xBi4.46Ce0·04Ti4O15+ybased ceramics is increased to 686.0 °C, which will enable the ceramics to be used in oilfield logging, aerospace and military fields in high temperature environment.

In this present exploration, chitosan doped with different lanthanide oxides such as CeO2, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Dy2O3 and Ho2O3 has been prepared and its optical and thermodynamical properties were studied as a function of the ion size of the lanthanide element and its atomic masses. From the refractive index measurement, the space-filling factor and polarizability have been obtained. The propagation of ultrasonic waves like ultrasonic velocity and its derived quantities such as relaxation strength (rs), adiabatic bulk modulus (Ks), acoustic impedance (Z) and adiabatic compressibility (β) have been obtained for different Chitosan-Lanthanide oxides (Ch-LnO). FTIR studies confirm the formation of different Ch-LnO. The variation of all the said properties with ion size is opposite to that of atomic mass due to lanthanide contraction. The results are presented and discussed in a detailed manner.

The development of accurate force fields of energetic molecules (EM) to predict their crystal structures has been aggressively pursued in the EM research community. In this study, a non-empirical polarizable force field for energetic molecules is derived from the quantum-mechanical (QM) calculation results to well describe intermolecular interactions. We named this force field as the energetic molecule specific polarizable force field (EMS-PFF). It includes anisotropic atomic multipoles to describe the electrostatic interactions, atomic polarizability to consider the electron polarization, and standard MM2-type Buckingham dispersion-repulsion van der Waals interactions. Different from the traditional force fields by fitting some observed properties, EMS-PFF is parameterized only from the QM calculation results of energetic molecule at the MP2/6-311g(d,p) level. The QM-derived EMS-PFF is applied to optimize the 174 conversional CHNO energetic molecular crystals listed in the paper published in J. Phys. Chem. B 2004 108, 17730-17739. Our results demonstrate that EMS-PFF can better reproduce the experimental crystalline structures compared with the rigid optimization by the traditional isotropic charge-based Dreiding and COMPASS force fields. We believe that the non-empirical EMS-PFF can not only well predict the crystalline structures of the conversational CHNO energetic molecules, but also predict the crystal structures of other new high-nitrogen or full-nitrogen energetic materials.

A system of bio-silica borotellurite glasses was fabricated based on the chemical formula [(TeO2)0.7 (B2O3)0.3]1-x (SiO2)x with x = 0.1, 0.2, 0.3, and 0.4 using the melt-quenching technique using silica (98.548% SiO2, from rice husk), TeO2 (Alfar Aeser, 99.9%) and B2O3 (Alfar Aeser, 99.9%). Measurements and characterizations such as density and molar volume measurements, XRD analysis, FTIR, and UV–Vis spectroscopes were performed on the studied glasses. The objective was to determine the glasses’ applicability in optoelectronics, non-linear optics, and laser technologies through polarizability, linear electric susceptibility, and optical basicity study. Apart from confirming the amorphous nature of the glasses, the XRD analysis identified the presence of a crystalline phase of tellurium oxide (α-TeO2) formed. The FTIR spectral study revealed the presence of TeO3, BO3, and SiO4 structural units in the studied glasses. The refractive index (2.3026 – 2.2651), molar polarizability (8.0696 – 9.4334 A3), oxide ion polarizability (3.2970 – 3.6202 A3), electronic polarizability (0.2296 – 0.2335 A3), dielectric constant (5.1307 – 5.3019), optical basicity (0.6719 – 0.7998), metallization criterion (0.410853 – 0.420714) and electric susceptibility (0.3286 – 0.3422 esu) of the glasses were presented. With the high refractive index and favourable electronic/oxide ion polarizability as well as good electric susceptibility, the glasses have shown great potential for optical fibre and laser applications. Metallization criterion value falls in the range of glasses with great potentials for non-linear optical application. The dielectric value suggests the glasses represent wideband semiconducting glasses believed to be good for application in microelectronic substrates fabrication.

The influences that Cu substitution has on the microwave dielectric properties of Li2Mg0.6Zn0.4SiO4 ceramics that were prepared via solid-state reaction were investigated using microstructure analysis, Raman spectroscopy, and chemical bond characteristics. The relative permittivity increased with an increase in the relative density, and the highest Q × f value was obtained with the most compact and uniform microstructure. Cu substitution reduced the sintering temperature and caused the molecular polarizability and bond ionicity to continuously increase, this resulted in the er value increasing linearly. Also, the stability and degree of order of the structure first increased and then decreased. Furthermore, Cu substitution improved the temperature stability of the samples. Specifically, Li2Mg0.56Cu0.04Zn0.4SiO4 that was sintered at 925 °C exhibited satisfactory properties (er = 5.628, Q × f = 58,742 GHz and τ f = −59 ppm/oC), and these make the ceramics promising for use in microwave applications.

Single crystals of L-threonine doped zinc tris thiourea sulphate, a semi-organic nonlinear optical material was successfully grown by the slow evaporation technique. The crystalline nature and structural parameters of L-threonine doped ZTS crystal have been confirmed by single-crystal XRD analysis. The substantial enhancement in mechanical strength of ZTS crystal due to the incorporation of L-threonine has been carried out with Vicker’s microhardness analysis. The second harmonic generation (SHG) efficiency of the crystal has been confirmed by standard Kurtz-Perry powder analysis. Further, the electrical properties, such as plasma energy, Penn energy, Fermi energy, and electronic polarizability of the grown crystals have been theoretically calculated and compared with the classical Clausius–Mosotti equation.

Polypyridyl coordinating ligands are common in metal complexes used in medicinal inorganic chemistry. These ligands possess intrinsic cytotoxicity, but detailed data on this phenomenon is sparse, and cytotoxicity values vary widely and are often irreproducible. In order to provide new insights into the biological effects of bipyridyl type ligands and structurally related metal-binding systems, reports of free ligand cytotoxicity were reviewed. The cytotoxicity of 25 derivatives of 2,2′-bipyridine and 1,10-phenanthroline demonstrates that there is no correlation between IC(50) values and ligand properties such as pKa, log D, polarizability volume, and electron density, as indicated by NMR shifts. As a result of these observations, as well as the various reported mechanisms of action of polypyridyl ligands, we offer the hypothesis that biological effects are governed by the availability of and affinity for specific metal ions within the experimental model.

The study of polarizability, optical basicity, and electric susceptibility carried out on the new and very rare set of bismuth - tellurite glasses doped with Ho3+ ions were fabricated by the conventional melt quenching process. The non-crystalline nature was confirmed by X-ray diffractometer measurements. Physical properties such as rare earth ion concentration, interionic distance, polaron radius, and average tellurium - tellurium separation were investigated by appropriate formulae. By UV absorption spectra, optical properties of Ho3+ ions doped glasses were found in the wavelength limit from 400 to 700 nm. The optical properties like optical dielectric constant, electronic polarizability, metallization criterion, electronegativity, optical basicity, and electric susceptibility were measured with appropriate mathematical relations. The impact of Ho3+ ions on nonlinearity in optical parameters discloses bismuth tellurite glass as a new applicant for holmium doped fiber amplifier applications.

A series of borobismuthate glasses doped with MnO with 0, 0.2, 0.4, 0.6, 0.8 and 1 mol% were prepared by melt quenching technique. X-Ray Diffraction (XRD) studies confirms the amorphous nature of samples. The parameters density, molar volume, molar refraction and oxygen packing density (OPD) were calculated and it is observed that density decreases and molar volume increases with increase in MnO component due to formation of Non Bridging Oxygens (NBO). Optical absorption studies were done for glass samples and it shows that optical bandgap energy (Eopt) and metallization criterion (M) decreases with increase in MnO component indicates that these glasses can behave as amorphous semiconductors. Apart from this the optical parameters such as linear refractive index (n), coefficient of absorption (α), coefficient of extinction (K), optical conductivity (σop), optical polarizability (αo) and optical basicity (Λth) have also been evaluated for all samples and studied as a function of wavelength.

The calculations of spectroscopic characteristics, non-linear optical properties, HOMO-LUMO energy band gap, molecular electrostatic potential surface, chemical reactivity descriptors and thermodynamic parameters of Isodihydrocadambine-4-Oxide using density functional theory as well as its protein-ligand interactions using molecular docking approach have been discussed in the present study. The theoretical 1H and 13C NMR chemical shifts have been found in good conformity with the corresponding experimental values. The maximum peak in IR spectrum has been calculated to be occurred at 1048 cm−1 vibrational frequency. The UV–visible absorption peak has been observed to be occurred at 712 nm resulting from electronic transitions HOMO + 1 → LUMO + 6, HOMO + 1 → LUMO + 8. The calculated value of dipole moment of the title compound is found to be 3.14 Debye which is 2.29 times greater than that of urea. The first order hyper polarizability has been calculated to be 6405.41 × 10−33esu which is 18.66 times greater than that of Urea indicates that it is non-linear optically active. The HOMO- LUMO energy band gap has been calculated to be practically small ≈0.12 a.u. and MESP surface to be suited for the recognition of receptor molecule required for the drug activity. The zero-point energy of this molecule has been obtained to be 387.75Kcal/Mol. The binding with 1HSG, 1GCN, 2NMO and 3I40 protein receptors of this bio molecule has been obtained through the virtual screening to project the title molecule to be multifunctional natural drug agent. It is, therefore, concluded that the said bioactive natural molecule may be explored as a multifunctional material for variety of applications and the present study may form a theoretical basis for the study of biologically active naturally occurring macromolecules.

Nonlinear and linear optical traits of vanadio–tellurite glasses in the form 50TeO2-(50-x)V2O5-xK2O (where x = 0–20 mol% (abbreviated as TVK glasses) were investigated. Besides, gamma ray shielding parameters were assessed utilizing the FLUKA simulation code. Results revealed that the molar refraction (Rmolar) varied from 31.122 to 26.400 (cm3/mol), while molar polarizability (αmolar) varied from 12.350 × 10−24 to 10.476 × 10−24 cm3. The static dielectric constant (estatic) was within 10.298–6.789. The optical electronegativity (χ*) varied from 0.319 to 0.626 for TVK glasses. The nonlinear refractive index (nOptical) diminished from 5.996 × 10−10 to 1.109 × 10−10 (esu), while the nonlinear optical susceptibility (χ3) diminished from 5.107 × 10−11 to 0.767 × 10−11 (esu) with the V2O5/K2O substitution in the glasses. Gamma ray attenuation coefficients such as μ and μ/ρ were calculated for six different photon energies in the range of 0.284–1.275 MeV. Both μ and μ/ρ were used to evaluate the transmission factors (HVL and MFP) and the effective atomic number (Zeff). The Zeff parameter was useful to give a full understanding of the gamma ray shielding performance of the TVK glasses under V2O5/K2O substitution. Finally, the parameters of gamma ray shielding were compared with ordinary and commercial shielding materials.

Optimized molecular geometry, occupied maximum molecular orbital energy, mulliken atomic charges, unoccupied lowest molecular orbital energy, molecular electrostatic potential, dipole moment, first-order hyperpolarizability and polarizability of 3-bromo-2-methoxy benzonitrile is projected using 6–311++G(d, p) basis set of density functional theory (DFT) calculations. The spectrum of Fourier Transform Infrared (FTIR) as well as FT-Raman were explored and validated with the observed results. Hyperpolarizability of first order determined with the quantum chemical calculations illustrate the preferred compound as effective agent in the nonlinear optics for future applications. DFT was researching thermodynamic properties like enthalpy, entropy and Gibb’s free energy.

Cordierite ceramic is one kind of important electronic materials for radio frequency circuit. In this work, Mg2-x (Li0.5Ga0.5)xAl4Si5O18 (0 ≤ x ≤ 0.1) ceramics with pure cordierite phase, were successfully synthesized via the traditional solid state reaction method. The dependence of microwave dielectric properties on the crystal structure was analyzed in detail by the complex chemical bond theory (P–V-L theory) and classical dielectric polarizability theory. The dielectric constant (er) was mainly related to the density, bond ionicity and ionic polarizability of Mg2-x (Li0.5Ga0.5)xAl4Si5O18 ceramics. The quality factor (Q × f) was in relationship to the lattice energy, atomic packing fraction and centrosymmetry of [Si4Al2O18] hexagonal ring in cordierite crystal structure. The temperature coefficient of resonant frequency (τf) value was dominated by the bond energy and distortions of [MgO6] octahedron. The maximum values of Q × f = 50,560 GHz and er = 4.72 were obtained for undoped Mg2Al4Si5O18 and Mg1.98Li0.01Ga0.01Al4Si5O18, respectively.

The influences of Sr2+ doping on microwave dielectric properties of Ca1-xSrxMgSi2O6 (x = 0–0.06) ceramics were researched in the work. The intrinsic mechanism responsible for the dielectric properties was explored by the P–V-L theory and Raman spectra. X-ray diffraction revealed that Ca1-xSrxMgSi2O6 solid solutions were formed when x = 0.02–0.06. The er continually increased with an increasing x value, which was related to the average bond ionicity and dielectric polarizability. The change of Qf was due to the variation in Si–O bond. The τf was affected by the Ca/Sr–O bond energy. Furthermore, the Ca0·96Sr0·04MgSi2O6 ceramic sintered at 1320 °C possessed optimum dielectric properties (er = 8.17, Qf = 85858 GHz, and τf = −41.25 ppm/°C).

The mechanical features, linear and non-linear optical properties and the radiation (beta/gamma) shielding competences of (90-x)TeO2–5CaO–5Na2O-xZnO: x = 5–20 mol% glasses were studied. Results revealed that the molar polarizability (αMol.) decreased from 6.215 × 10−24 to 6.009 × 10−24 cm3 and the molar refraction (RMol.) changed from 15.664 to 15.143 (cm3 mol−1) as the ZnO content increased from 5 to 20 mol%. The criterion of metallization (MCri.) was observed in the range of 0.419 to 0.384. The factor of optical transmission (TOpt.) decreased from 0.814 to 0.788. The dielectric constant (eSta.) varied from 3.763 to 4.202. The electro-negativity (χ*) decreased from 0.943 to 0.792. The non-linear optical susceptibility (χ3) changed from 3.984 × 10−13 to 7.185 × 10−13 esu. The non-linear refractive index varied from 0.739 × 10−11 to 1.320 × 10−11 esu. The radiation shielding properties of the chosen glasses (TCN-Z05, TCN-Z10, TCN-Z15, and TCN-Z20) were tested in terms of gamma radiation (photons up to 1.275 MeV) and beta radiation (electrons up to 0.723 MeV). The gamma shielding investigations were performed by using FLUKA and XCOM platforms. The beta shielding study was carried out via ESTAR program by estimating TSP for all the chosen glasses. From the view of practical application, it is found that the HVL and MFP values of the chosen glasses are evidently lower than those of ordinary concrete and RS-253-G18 commercial glass, while they are higher than those of RS-360 glass at low energies.

The Mg1-xNa2xWO4 (0 ≤ x ≤ 0.14) microwave dielectric ceramics were prepared through traditional solid-state reaction and sintered at 875−925 °C for 4 h. Compared with pure MgWO4 ceramic, the samples with substituting Na+ for Mg2+ could be sintered at a lower temperature, the quality factor values and the densification of microstructure were obviously improved. Raman spectroscopy proved that the relative permittivity was related to the multiple phases and molecular polarizability. In addition, the distortion of [MgO6] octahedron also changed, resulting in resonance frequency temperature coefficient varied nonlinearly from x = 0 to 0.14. Considering the applications of low temperature co-fired ceramics technology, the Mg1-xNa2xWO4 (x = 0.06) ceramic sintered at 875 °C had the best performance. Not only did it have excellent microwave dielectric properties of e r = 10.474, Q × f = 45,868 GHz, and τ f = −69 ppm /oC, but also presented great chemical compatibility with the commonly used Ag electrode.

The influence of Ag2O on the linear and nonlinear optical parameters of ternary silver vanadio-tellurite glasses, with a chemical formula of 40TeO2-(60-y)V2O5-yAg2O where y = 0–50 mol% in increments of 10 mol%, was investigated. The effect of Ag2O on the gamma-ray shielding properties of the investigated glasses was evaluated utilizing the recently released Phy-X/PSD program. The results revealed that the linear optical refractive index varied between 2.47 and 2.66 for the studied glasses. The molar polarizability (αmolar) decreased from 14.125 × 10−24 to 9.634 × 10−24 cm3, while the molar refractivity (Rmolar) varied from 35.596 to 24.279 (cm3/mol) as the Ag2O concentration increased from 0 to 40 mol%. The metallization criterion (Mcriterion) varied from 0.246 to 0.280, while the optical transmission factor (Toptical) increased from 0.656 to 0.694. The static dielectric constant (estatic) changed from 6.624 to 7.128, while optical electronegativity (χ*) increased from 0.580 to 0.731. The nonlinear optical susceptibility (χ3) varied from 6.923 × 10−12 to 9.637 × 10−12 esu, while the non-linear refractive index changed from 0.722 × 10−10 to 1.360 × 10−10 esu. The T40V60A0 glass sample (with no Ag2O) has the lowest μ/ρ and can shield 50.3% of the photons at an energy of 0.284 MeV, while T40V10A50 has the highest μ/ρ and can shield 78.5% of a beam of photons with the same energy. The MFP at 0.284 MeV has the following values: 2.145, 1.811, 1.470, 1.308, 1.130 and 0.975 cm for T40V60A0, T40V50A10, T40V40A20, T40V30A30, T40V20A40 and T40V10A50 glasses respectively. Altogether, the results demonstrated that the greater the Ag2O content in the glasses, the lower the TF, and thus the more effective the radiation shield. The investigated glasses have a great possibility of being applied in several optical applications.

We demonstrate the preparation of NaY(WO4)2 phosphor particles with 1 mol% Ho3+ and various Yb3+ and Li+ via solid-state reaction. The X-ray diffraction and infrared absorption spectrum results show that Yb3+ and Li+ would shrink the crystal lattice owning to their much smaller ionic radius. However, the W–O bond has been altered by Li+ due to its stronger polarizability, and thus enlarges the crystal lattice parameters when Li+ concentration is relatively high. According to the scanning electron microscope images, the mean size of Li+ doped samples distribute from 1.75 μm to 2.58 μm. The up-conversion properties are studied under 980 nm laser diode excitation. All samples demonstrate two typical emission peaks located around 544 nm and 660 nm, which are corresponding to the 5S2/5F4→5I8 and 5F5→5I8 transitions in Ho3+. Pump power law coefficients infer that both 544 nm and 660 nm emissions involves two-photon processes. Additionally, doping of Li+ would significantly increase the green and red emissions intensities, with maximum enhancement of 3.65-fold and 7.51-fold, respectively. From Judd-Ofelt theory, the increasing intensity at 544 nm might attribute to the tailoring of local symmetry around Ho3+, thus enlarging Ω2 value. For the 660 nm emission, some promoted non-radiative relaxation processes could account for its great enhancement. The prolonged fluorescence decay lifetimes would make their great enhancement well comprehended. The notable enhancement in red emission would move the color-coordinates from green region to yellow-green regions, thus making it a novel candidate for multi-color materials to be further investigated.

Structural features of the glass family xLi2O- yMgO (4.8 Bi2O3 47.6 P2O5) obtained by melt quenching technique were studied taking into account the density, FTIR and UV–vis spectra and also the electrical response observed by impedance spectroscopy. In this work it becomes clarified how the alkaline earth oxides stabilize the glassy matrix and also, the fundamental importance of determining the optimal proportion in order to obtain a flabby easily polarizable matrix to enhance the electrical behavior due to a boosted cation mobility. It is evidenced that when the glass composition becomes complex it is needed to take into account a larger number of structural parameters to understand, to predict or to design the resulting physical properties.

Based on the quantum chemical descriptors and the activities for isoprene polymerization of 12 neodymium carboxylates obtained by authors' earlier work, statistical analysis of data was made and a QSAR model correlating the quantum chemical descriptors and the activity was built with the partial least square (PLS) approach. The model is: A = 51,602 eHOMO + 6 σ + 12,546, which indicates that the catalytic activity A is positively correlated with the HOMO energy eHOMO and the ligand polarizability σ, with the contribution of σ being larger, eHOMO smaller. The model's coefficient of determination r2 = 0.96 and that of cross validation q2 = 0.94, both being close to 1, which means that its quality is well and its predictive power is strong. Analysis of the modeling process and the resulted QSAR model, together with the interpretation of the model's mechanism, also shows that the model obtained from this study is valid and reliable. According to the QSAR model, the mechanism of catalyst activity can be interpreted as that neodymium carboxylates with higher HOMO energy and larger ligand polarizability are easier to react with the co-catalysts so as to produce more active and stable centers of catalyst, resulting in a higher activity.

Core-shell structured magnetic Fe3O4@glutathione composite nanoparticles were synthesized and examined using diverse methods including Fourier-transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray analysis, transmission electron microscope, thermogravimetric analysis, and vibrating sample magnetometer analysis. In addition, the nonlinear optical measurements were performed by both open and closed aperture z-scan methods using an aqueous colloidal solution of the fabricated nanoparticles. The colloidal system exhibited a positive nonlinear refractive index because of the self-focusing effect arising from optical re-orientation. Although optical re-orientation is a rare phenomenon in nanocolloids, high polarizability of the enveloping organic ligands caused optical re-orientation of the composite nanoparticles in the electrical field direction of the incident beam. Finally, the effect of external voltage on the nonlinear optical index was further investigated.

Structure with the asymmetric environment of cation has a large effect on the polarization mechanism and dielectric response. In this study d0 cation, Ti4+ is introduced into asymmetric α-TeO2 to prepare TixTe(1-x)O2 (x = 0 to 0.25) by conventional solid-state method. In all the samples, it is found that the dielectric response increases relative to the parent α-TeO2. Sample with x = 0.25 forms cubic TiTe3O8 phase and shows maximum dielectric permittivity of 77. The remaining samples show biphasic nature comprising cubic (TiTe3O8) and tetragonal (α-TeO2) phase and their dielectric behaviour follows the Lichtenecker logarithmic mixing rule of composites. Structural analysis reveals that the cubic TiTe3O8 phase consists of TeO4 and TeO6 framework structure with locally strained TeO4 units compared to α-TeO2 and the Raman study complements this observation. The local strain enhances the dipolar polarizability of TeO4 unit; additionally, ionic polarizability of TiO6 unit also contributes to high dielectric permittivity in TiTe3O8.

xCaTiO3-(0.8-x)SrTiO3-0.2BiFeO3 (x = 0, 0.3, 0.5, 0.7) ternary solid solution ceramics were prepared by a conventional high temperature sintering method. The structural and electrical properties of these ceramics were studied comprehensively. 0.3CaTiO3-0.5SrTiO3-0.2BiFeO3 ceramics show large dielectric permittivity and small variation over a broad temperature range, making it a potential candidate for high-temperature electronic applications. The origin of the large dielectric permittivity is discussed based on the contributions of both A-site and B-site cations on the polarizability of the system. The multiple cations induced local structural heterogeneity and/or random field is proposed as the reason for the thermal stability of dielectric permittivity.

Electronic polarization has an important impact on the site energies of charge carriers that play a key role in determining the charge transport in organic semiconductors. Dipolar molecules have strong intermolecular interactions and widespread applications in organic optoelectronics. However, compared with nonpolar organic semiconductors, electronic polarization for dipolar systems has been rarely studied. Here, taking 1,2,3,4-tetrafluoro-6,7-dimethylnaphthalene as representative, we have calculated the electronic polarization energies of dipolar organic molecular crystals by means of a polarizable force-field method. Surprisingly, our results point to that the polarization energies for this dipolar system are similar to those of nonpolar systems. In addition, the π-π stack contributes only about 30%∼40% to the total polarization energy, thus the polarization effects along the three dimensions should be treated equally even for the one-dimensional stacking crystals.

Surface-enhanced Raman spectroscopy (SERS) has single molecule level bio-chemical detection capabilities. Single layer graphene on SERS substrates shows modest enhancement factor (EF) (∼10) primarily from chemical enhancement (CE) mechanism. Improvement in EF will have significant impact on applications of graphene in optoelectronics. This limitation is caused by poor interaction of visible light at near infrared frequencies with graphene monolayers. We report an assembly of single-layer graphene (SLG) on a three-dimensional (3D) Au@Ag, core-shell structure that enhances light-matter interactions and modulates light absorption in graphene due to formation of graphene ripples. We demonstrate a SERS EF of ∼1,000 using 633 nm excitation laser with the designed SLG/SERS substrate. The Raman scattering cross-section of R6G molecule was found to be enhanced by a factor of ∼102–103, and limit of detection obtained was 100 pM using the SERS substrate. The enhancement is primarily due to increase in polarizability and anisotropy from rippled graphene substrate. The finite-difference-time-domain electromagnetic simulation showed enhancement of local electromagnetic field leading to enhanced excitation of the molecule. Density functional theory based quantum mechanical simulation studies showed the charge transfer from graphene-to-R6G molecule, leading to enhanced emission of Raman scattering.

In this study, we have evaluated the optoelectronic and piezoelectric properties of doped PVDF. The electronic structures and the linear and non-linear optical properties of ZrO2-doped PVDF were calculated by adopting the LDA approximations for the exchange-correlation potential in the DFT method integrated in Gaussian 09. Optoelectronic parameters and ground state molecular geometry were calculated using B3LYP functional and LanL2DZ as the basis. We chose the calculation with the B3LYP functional because it is a relatively inexpensive and it is precise method to predict molecular structures, energies and frequencies. In this work, some optical parameters and constants such as refractive index, electrical susceptibility, dipole moment, average polarizability and hyperpolarizability, phase velocity have been calculated. Dielectric constants, ionization potentials, electronic affinities, electronegativities, hardness and flexibility were also calculated. Finally, the piezoelectric properties such as the piezoelectric coefficient and the pyroelectric coefficient are evaluated. The calculated electronic structures show that virgin PVDF, hybrid molecules PVDF/2ZrO2 and PVDF/3ZrO2 have an Egap less than 3 eV. On the other hand, the hybrid PVDF/ZrO2 molecule is a good dielectric and therefore a good piezoelectric nanocomposite because its Egap is 5.89 eV greater than 3 eV. Finally, the results show that the hybrid molecules PVDF-2ZrO2 could have potential applications not only as piezoelectric materials but also as semiconductor components, nonlinear optical materials and possible building materials for molecular electronics and photonic devices.

The electronic structure, spectroscopic (IR, Raman, NMR) and NLOs properties of Rubescin D have been evaluated. Good agreement with experimental results were found for 3JH-H coupling constant, IR intensity, 1H NMR, and 13C NMR. The IR and Raman vibrational frequencies were interpreted. The global reactivity descriptors were calculated. Hyperpolarizability, polarizability, dipole moment and energy gap values permit us to conclude that Rubescin D, has good linear and nonlinear optical applications and can be used as insulator in many electronics devices. During polarization of Rubescin D, the charge is transfer between the x and y direction.

In this work, the DFT method (B3LYP) with the base 6-31+G** was used to study the influence of doping on the molecule 2-cyano-3- [4- (diphenylamino) phenyl] acrylic. To do this, the dipole moment (μ), the polarizability (α0), the anisotropy of the polarizability (Δα), the hyperpolarizability (β0), the gap HOMO-LOMO (HL gap), the dielectric constant (e), the electric susceptibility (χ), the refractive index (η) and the thermodynamic properties of the different molecules have been calculated. The polarizability, the first hyperpolarizability and the HL gap enable us to conclude that the doping with titanium dioxide leads to new interesting molecules for applications in the design of new nonlinear and optoelectronic materials.

A semi-relativistic approach is employed to calculate elastic differential, integral, and momentum transfer cross sections as well as total (elastic plus inelastic) cross sections for the scattering of electrons from silver, platinum, and gold atoms in the energy range 0.1–100 eV. The projectile-target interaction is composed of real (i.e. the sum of static, exchange, and polarization) and imaginary (i.e. absorption) potential. The total optical potential is then used in the solution of the Dirac equation for the scattered electrons. The characteristic features [Ramsauer-Townsend (RT) minimum and shape resonance] which are required for the fundamental understanding of the dynamic processes at the atomic level, are identified in the low energy region. The value of the RT minimum has been correlated with the scattering length to the dipole polarizability of the target atom. The calculated cross sections are compared with available theoretical calculations and experimental measurements in this energy region.

Organic light emitting diodes (OLEDs) have attracted electronics industry due to their lightweight, compactness, faster switching, flexibility etc. The N,N,N’,N’-tetraphenyl-1,4-phenylenediamine (TPA) is employed as a hole transporting material in OLEDs. Herein, we analyze molecular structure of CH3-functionalized TPA and compare their properties with TPA using Density Functional Theory (DFT) method. We have substituted CH3 in two diagonally placed phenyl ring systems at para- and meta- positions; and calculated dipole moment, mean polarizability, frontier orbitals energy and energy gap to compare their molecular properties. Our findings suggest that CH3 substituted at para-position of TPA may be better hole-transporting material for OLEDs.

The nonlinear optical (NLO) properties of the Indole-7-carboxyldehyde (I7C) have been investigated by computational and experimental (UV-VIS, Raman) data analysis. Mulliken charge analysis, molecular electrostatic potential, and UV-VIS absorption and vibrational Raman studies have been used to analyze the intra-molecular charge transfer occurrence in the probe system. Observed high value of dipole moment, linear polarizability and first order hyperpolarizability values suggest that the indole derivative may indeed have possibility to show good NLO behaviour.

DFT calculations of spectroscopic characteristics, NLO properties, HOMO-LUMO energy band gap, MESP surface, chemical reactivity, thermo-chemical parameters and molecular docking studies on the title molecule have been reported in this paper. The IR active vibrations, (proton, C13) NMR chemical shifts and UV–visible absorption peak have been observed to be in good conformity with the corresponding values measured experimentally. The small HOMO- LUMO energy band gap favors the high value of first order hyper polarizability which may be exploited for nonlinear optical applications of this molecule. It binds with 1HSG, 2NMO, 1GCN and 3I40 protein receptors which reveal its drug activity.

The study of HIV-1 and HIV-2 protease inhibition of amprenavir is of immense therapeutic interest, owing to its application in the design of drugs, for the treatment of AIDS. Since, the inhibition is dependent on the molecular structural features, the DFT aided FT-IR, 13C NMR and FT-Raman spectral and structural analysis have been carried out, to arrive at the structure activity correlation. The negative mesomeric effect (–M effect) induced by the sulphonamide group and the consequent electron flow through APS (aminophenyl sulphonamide) ring has been explored using DFT and QTAIM based spectral analysis. The charge redistribution in the ring and the changes in bond strength arising due to this electron flow, have been investigated using experimental and theoretical methods. The relative strength of resonance of oxygen and nitrogen lone pair with the carbonyl group, due to ‘competing resonance’, have been exploited, using relative change in IR stretching frequencies and bond lengths of C-N and C-O. The role of π-anion interaction, favored by the electron deficiency of APS ring due to –M effect and the cooperativity of bonding has been examined using ESP mapping, quadrupole moment and the polarizability perpendicular to the ring. The stable binding pose of amprenavir in the binding site of HIV-1 and HIV-2 and amprenavir-residue interaction, obtained from docking, have been confirmed respectively using RMSD and simulation interaction diagram, procured from molecular dynamics simulation.

The current work is to spotlight the key structure-property features of a novel thiourea complex bis(thiourea) silver(I) nitrate (BTSN) for future applications in nonlinear optical devices through dual approach involving experimental and theoretical techniques. The synthesis and growth of good quality single crystals of a relatively new material BTSN have been done. The crystal structure, quantitative and qualitative, vibrational, optical and dielectric analysis of the grown single crystals was carried out. The optical transparency of the grown crystals is found to be more than 80% confirms its colorless nature and applications in optoelectronic devices. Further, the state-of-art computational methods have been applied to obtain the ground state molecular geometry at B3LYP/6-31G∗, MP2/6-31G∗ and M06/6-31G∗ levels of theory. Various key electro-optical properties (complementary to experimental results) such as IR, Raman, and polarizabilities have been determined at the same levels of theory. The static and dynamic polarizability and first hyperpolarizability both were calculated to comprehend the potential applications of BTSN in nonlinear optics. In addition to the above, numerous novel molecular level insights have been achieved in the form of total and partial density of states, HOMO-LUMO gap and molecular electrostatic potential map. The calculated values of static and frequency dependent dynamic first hyperpolarizability are found to be 8.46 × 10−30 and 2.30 × 10−30 esu which are about 23 times and 13 times greater than those of prototype urea molecule, respectively, calculated at the same B3LYP/6-31G∗ level of theory. From the analyzed results it is clear that the titled compound possesses excellent electro-optic properties that make it a decent contestant for photonic devices. Keywords: Crystal growth, Optical properties, Nonlinear optical material, Density functional theory

1-Aryl-3-(4-bromophenyl)-4,4-dichloro-1,2-diazabuta-1,3- dienes were synthesized via copper-catalyzed reaction of 4-bromobenzaldehyde arylhydrazones with CCl4. X-ray diffraction analysis revealed non-covalent Cl···Br interactions in the crystalline state and formation of 3D supramolecular framework; DFT calculations and topological analysis of the electron density distribution within the framework of Bader's theory (QTAIM method) confirmed these observations. Theoretical calculations showed that highly polarizable dichlorodiazadiene unit is capable of acting as a relatively strong halogen bond donor.

The conformational isomerism and orbital interactions of N-(2-bromo-2-phenylethenyl)-N,N-bis(trimethylsilyl)amine and N-(2-bromo-2-trimethylsilylethenyl)-N,N-bis(trimethylsilyl) amine were examined using NMR technique and quantum-chemical calculations. The IR criterion characterizing σ→σ* hyperconjugation is considered, and the linear dependence of σC–H→σ*C–X (X = F, Cl, Br) interaction energy on the polarizability of X is discussed.

The trends of stability and polarizability have been computationally deduced for the sets of oxygen-containing fullerene derivatives C60O, C60O2 and C60O3 (2, 11 and 68 isomers, respectively).