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ABSTRACT Para‐phenylene‐bridged pyridinium (acceptor)–dicyanomethanide (donor)‐based zwitterions were computationally investigated and are reported here. Reichardt's metamer was found to be twisted and Brooker's metamer in near‐planar conformation. Natural bond orbital (NBO) analysis showed that mesomeric resonance is helping Brooker's metamer but found to be not helpful for Reichardt's metamer. To assess the impacts of metamerism and aromatic bridges, fundamental molecular properties like dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β), and adiabatic absorptions of these two molecules were analyzed and then directly compared with their counterpart zwitterions without any bridges (previously reported). Results of impact of metamerism: Reichardt's metamer showed around three times enhanced hyperpolarizabilities (ωB97xD: β = 1577.1 × 10−30 esu) than the Brooker's metamer (ωB97xD: β = 532.5 × 10−30 esu). Impacts of p‐phenylene bridges: Compared to their respective D–A directly connected zwitterions reported previously (in ωB97xD methodology, Reichardt's: β = 257.2 × 10−30 esu and Brooker's: β = 67.2 × 10−30 esu), respective p‐phenylene‐bridged zwitterions showed five to eight times enhanced hyperpolarizabilities. This report highlights the better efficiencies of Reichardt's metamer over Brooker's metamer and aromatically bridged over the directly connected zwitterions. Current findings may be helpful in the designing of efficient functional molecular chromophores, and aromatic bridge combined with zwitterions can be solutions to nonlinear transparency trade‐off problem. [ABSTRACT FROM AUTHOR]

K20 microwave dielectric ceramics SrLnAlO 4 (Ln = Eu, Gd, and Ho) were prepared at 1440–1520 °C. SrEuAlO 4 and SrGdAlO 4 crystallized into tetragonal K 2 NiF 4 -type structures. While SrHoAlO 4 was a mixture (SrHo 2 Al 2 O 7 , Ho 2 O 3 , and Sr 3 HoAl 2 O 7.5) due to the too-small radius of Ho3+ to bond in [HoO 9 ] dodecahedron. SrEuAlO 4 and SrGdAlO 4 exhibited near-zero τ f values of +1.7 and +4.3 ppm/°C and low ε r (19.37 and 19.14) along with contrasting Q × f values (70,030 and 5560 GHz). Compared with the modified molecular polarizability (α Corr) based on the bond valence deviation, the α obs values of SrEuAlO 4 and SrGdAlO 4 are much higher, indicating that their dielectric polarizabilities were underestimated, and this phenomenon was mainly influenced by rattling cations, which also causes their τ f with near-zero values. Due to the magnetic subsystem adversely affecting microwave dielectric losses, the worsened Q × f value of SrGdAlO 4 compared to that of SrEuAlO 4 is due to the high magnetic moment of Gd3+ (7.94 μ B). [ABSTRACT FROM AUTHOR]

We have done geometry optimization of two conformers of Lantadene series C and D. The fundamental vibrational frequencies with intensity have been done by using B3LYP/6-311G (d, p) method. The complete vibrational assignments of wavenumbers are made on the basis of potential energy distribution (PED). The nonbonding interactions in Lantadenes C and D are calculated by using the same level theory at the bond critical point (BCP). The calculated topological parameters at BCP are utilized to determine the nature and strength of interactions. We have also computed HOMO–LUMO gap and plotted frontier orbital HOMO–LUMO surfaces, molecular electrostatic potential surfaces to explain the reactive nature of Lantadenes C and D. The electronic transition spectra UV–Vis spectra of Lantadenes C and D are calculated by using TDDFT theory. The values of hyperpolarizability show a probable use of these compounds in electro-optical applications. The natural bonding orbital theory is utilized to calculate transition of electron from donor to acceptor which is very useful to describe nonbonding as well as bonding interactions. The calculated value of Log P and Log S for Lantadene C Lantadene D established its pharmaceutical behaviors. The biological activity of Lantadenes C and D is also calculated by using PASS online server for Pa > 7 0 %. The docking of Lantadene C Lantadene D is also performed by using Auto dock with predicted drug by Swiss dock online server. [ABSTRACT FROM AUTHOR]

The thermo-optic coefficients (TOCs), thermo-polarization coefficients (TPCs) and dn/dT, dα/dT of congruent lithium niobate LiNbO3 / LN (mole ratio Li/Nb = 0.946) are tested within the temperature range of 293–773 K at λ = 0.4358 µm, λ = 0.6328 µm and λ = 1.15232 µm employing the point dipole approximation. The refractive indices, no and ne, were first determined at these temperatures and wavelength ranges, by iterating the electronic polarizabilities of Nb5+ and O2+ ions. It has been found that the polarizability of Nb5+ ions drops and that of O2− ions increases when temperature rises for a particular wavelength. Both Nb5+ and O2− lose polarizability with increasing wavelength for a given temperature. TOCs for no and ne rise as the temperature rises. The TOC rises as wavelength for no and ne decreases. TPCs of O2− rise in ions and temperature causes Nb5+ ions to decrease. At a particular temperature, TPCs of O2−ions become less while Nb5+ ions grow as wavelengths rise. Generally, it is used in potential electronic polarizabilities and thermal refraction applications. [ABSTRACT FROM AUTHOR]

Plasmonic rulers (PRs) linking nanoscale distance dependence spectral shifts are important for studying cellular microenvironments and biomarker detection. The traditional PR design employs tethering metal nanoparticle pairs using synthetic and biopolymers that severely suffer from reproducibility issues, as well as lack reversibility. Here, the fabrication of novel PRs is reported through the formation of self‐assembled monolayers (SAMs) of photoswitchable molecular machines chemically tethered onto sharp‐tip gold nanostructures (Au NSs). This unique and highly sensitive PR utilizes localized surface plasmon resonance (LSPR) properties of Au NSs to spectroscopically evaluate dipole–dipole coupling between NSs and photoisomerizable spiropyran (SP)‐merocyanine (MC) conjugates in the solid‐state. It is observed that the SAM‐modified NSs are extremely sensitive to the photoisomerization of SP‐to‐MC, resulting in LSPR shifts as large as 5.6 nm for every 1.0 Å change in distance. The highly dipolar MC changes the NS‐SAM interfacial polarizability and alters the dipole–dipole coupling leading to the ultrasensitive PR is hypothesized. The hypothesis is supported theoretically by calculating dipole polarizability of an inorganic‐organic heterodimer model and experimentally by determining work function and interfacial dipole values. Taken together, this work represents the fabrication of next‐generation PRs, which hold great promise for advanced, plasmonic‐based sensors and optoelectronic device fabrication. [ABSTRACT FROM AUTHOR]

The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high‐performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry‐breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT‐1SO. The asymmetric structure of BBTT‐1SO proved beneficial for increasing multiple moment and polarizability. BBTT‐1SO‐containing polymers showed higher efficiencies for hydrogen evolution than their DBS‐containing counterparts by up to 166 %. PBBTT‐1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g−1 h−1 and an apparent quantum yield of 27.5 % at 500 nm. Transient spectroscopic studies indicated that the BBTT‐1SO‐based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT‐1SO also showed 14 % higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water‐PBBTT‐1SO polymer interactions in salt‐containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high‐performance photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

Organic materials with switchable dual circularly polarized luminescence (CPL) are highly desired because they can not only directly radiate tunable circularly polarized light themselves but also induce CPL for guests by providing a chiral environment in self‐assembled structures or serving as the hosts for energy transfer systems. However, most organic molecules only exhibit single CPL and it remains challenging to develop organic molecules with dual CPL. Herein, novel through‐space conjugated chiral foldamers are constructed by attaching two biphenyl arms to the 9,10‐positions of phenanthrene, and switchable dual CPL with opposite signs at different emission wavelengths are successfully realized in the foldamers containing high‐polarizability substitutes (cyano, methylthiol and methylsulfonyl). The combined experimental and computational results demonstrate that the intramolecular through‐space conjugation has significant contributions to stabilizing the folded conformations. Upon photoexcitation in high‐polar solvents, strong interactions between the biphenyl arms substituted with cyano, methylthio or methylsulfonyl and the polar environment induce conformation transformation for the foldamers, resulting in two transformable secondary structures of opposite chirality, accounting for the dual CPL with opposite signs. These findings highlight the important influence of the secondary structures on the chiroptical property of the foldamers and pave a new avenue towards efficient and tunable dual CPL materials. [ABSTRACT FROM AUTHOR]

Context: This work reports structure–property correlations of 27 zwitterions Reichardt's types of zwitterions. Focuses are twofold, to see the (1) impacts of metamerism with Reichardt's vs Brooker's types of zwitterions and (2) impacts of monocyclic aromatic rings as bridges. All the molecules considered here have pyridinium (common acceptor: A) and p-phenylene-dicyanomethanide (common donor: D). Fundamental molecular properties like dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β), and adiabatic absorptions were computed only for the Reichardt types and compared with the literature reported respective Brooker's types of zwitterions. As an impact of metamerism, in general 2–3 times enhanced hyperpolarizabilities (β) were observed for Reichardt's compared to Brooker's types. Exceptions were observed with some triazine bridges and furan bridge, where Brooker's types were found to be more efficient. As impacts of aromatic bridges, in general, 6–sevenfold enhanced β compared to well-known traditional bridges and enhanced β were observed compared to D-A directly connected zwitterion (benzene bridge: sixfold enhanced β). Current findings show that the aromatic bridge control with Reichardt's types of zwitterions is more efficient and thus may be employed as an effective strategy for the designing of functional molecular chromophores for various other fundamental areas. Methods: All computations were performed with Gaussian 09. Geometry optimizations and computations of fundamental properties were carried out with HF, B3LYP, CAM-B3LYP, and ωB97xD methodologies, with 6-31G(d,p) and aug-cc-pVDZ basis sets. For adiabatic excitations, computations were carried out using TDDFT and TDHF approaches. For the computations of the response properties (like the nonlinear optical responses), CPHF approach was used. [ABSTRACT FROM AUTHOR]

Progress in glass science has given rise to innovative functional glasses, unlocking significant applications for creating cutting-edge materials such as solid-state batteries, solar cells, optical reinforcement, and medical technologies. In this study, rice husk silica, Bismuth (Bi) and Tin (Sn) oxide ores were used to fabricate a novel glass series. The electrical conductivity (i.e., dielectric constant) of the glasses increased with the dopant's gravimetric levels. The novel glass series also possesses good optical non-linearity with metallisation criteria ranging from 0.35 to 0.40, which points to a novel non-linear optical material. The non-bridging oxygen content in the new glasses exceeds the bridging oxygen, indicating high polarisation. The transmission coefficient decreased with increasing dopant concentration from 0.76 to 0.75, while the reflection loss decreased from 0.37 to 0.38. For the Caesium-137 energy, GS6 has a minimum HVL of ∼5.02 cm, which is ∼20 % lower than that of commercial Pb/Ba glass. For the two energies, GS6 has the least MFP, suggesting that the addition of dopants improved the efficiency of the glass attenuation. Process capability analysis based on Caesium-137 (661.7 keV) and overall performance analysis of the fabricated glass series revealed that GS3 glass (15 wt% dopant) is the optimal material, even outperforming the commercial Pb/Ba glass. Although Cobalt-60 (1253 keV) yielded comparable outcomes, concentrations beyond 15 wt% in GS3 showed marginal enhancements in the photon attenuation parameters of the glasses. Hence, the fabricated GS3 and the circular synthesis method of the glasses are cost-effective for low-energy gamma/X-ray shielding. The percentage deviation between the experimental data for MAC and that of Monte Carlo simulations for Cs-137 and Co-60 energies are both within 10 %, which validates the methods of this paper. [ABSTRACT FROM AUTHOR]

Polyimides (PIs) are widely used materials due to their high thermal stability and potentially low dielectric constant (Dk) and dissipation factor (Df). However, Dk and Df values tend to increase at higher frequencies. Therefore, there is a significant need to reduce the Dk and Df values of PIs, which is the main purpose of this study. This research considers multiple factors, including the ring structures and conjugations on the conformation of the PI backbone. The effects of five‐membered and six‐membered PIs and the conjugated length of benzene and naphthalene structures in the repeating units on the thermomechanical and dielectric properties are systematically investigated. As a result, the PI with a six‐membered imide contributes to higher thermal stability, with a glass transition temperature higher than 350 °C, a thermal decomposition point of 529 °C, and a lower Dk of 2.7–2.8. Still, it exhibits a lower molecular weight than that of a five‐membered imide. On the other hand, PIs with esterified structures show an extremely low Df value, 0.002–0.005. This situation can be attributed to the vital correlation between the Df and the volumetric dipole moment. This study also presents the different properties arising from ring structures and conjugations. Meanwhile, the relationships between Dk and volumetric polarizability and between Df and volumetric dipole moment are confirmed. This work provides a guideline for the structure−dielectric relationship of PI at a high frequency of 10–40 GHz. [ABSTRACT FROM AUTHOR]

Previously synthesized six selected Pyridinium‐Benzimidazolate based zwitterions were investigated in this contribution. Of the selected molecules, two are TICT, two are PICT (twisted and planar intramolecular charge transfer types respectively), and the other two are PICT+TICT types. Generally, TICT vs PICT is the most widely used strategy for chromophore design by earlier researchers. In this work, impacts of PICT+TICT effects (two effects combined in one chromophore), through p‐phenylene bridges, on various fundamental properties like, dipole moments, polarizabilities, hyperpolarizabilities, adiabatic excitations were analyzed. Nonlinear optical (NLO) responses of the six molecules indicate that PICT more efficient than TICT (6‐11‐times enhanced β), and PICT+TICT more efficient than both PICT (~4 times enhanced β) and TICT (20–40 times enhanced β). Current work also shows the role of aromatic p‐phenylene bridge as an efficient communicator between the donor and acceptor, in enhancing the NLO and other response properties. This work suggests that inducing bridge aromatic control to a TICT chromophore (making it to exhibit an amalgamation of PICT and TICT effects) is an effective and efficient strategy in the designing of molecular nonlinear optical chromophores, over either PICT or TICT only. [ABSTRACT FROM AUTHOR]

To overcome the energy limitations of conventional Li‐ion batteries (LIB), renewed attention has been given to Li‐metal anodes, which provide the highest capacity and lowest anode potential. To realize Li‐metal batteries (LMBs), it is crucial to stabilize unwanted side reactions on the surface and to inhibit problematic dendrite growth, which causes short‐circuit issues. Herein, diverse pyrrolidone‐based molecular dipole additives controlled by different functional groups are introduced as trifunctional surface stabilizers. It is discovered that the Li–Li symmetric cell improves proportionally with the molar volume and corresponding polarizability values of the molecular dipoles. The highly polarizable pyrrolidone‐based molecular dipoles offer exceptional benefits, including surface flattening of the Li metal anode, controlling the growth direction of crystalline Li, and forming durable solid electrolyte interface (SEI) components. The study is based on polarizability‐controlled molecular dipoles, and offers an effective approach for designing advanced surface stabilizers to develop of high‐performance LMBs. [ABSTRACT FROM AUTHOR]

An interpretation is proposed for the dependence of the melting temperatures of an entire subclass of alkali metal halides on the chemical composition, based on an analysis of changes in different contributions to the internal energy of salts in the molten and crystalline phases with variation in the sum of the radii of their cations and anions. The expression for calculating the energy of liquid salt melts includes the contribution from charge–dipole interactions between ions, which is considered in a work based on thermodynamic perturbation theory with a basis in the form of a model of charged hard spheres. The Born–Mayer formula is used for the energy of the crystalline phase in the electrostatic part, while Debye's formula is employed to consider the contribution from vibrations. An explanation is given for the lower values of the reduced melting temperatures of lithium and sodium halides, relative to other salts. It is shown that deviations of the reduced melting temperatures of lithium and sodium halides depending on the sum of ionic radii can be explained by Coulomb and translational contributions to the energy in the molten state, along with Madelung and Born contributions in the crystalline phase. [ABSTRACT FROM AUTHOR]

Optimization of nine bis-Schiff bases derived from 5-substituted-8-aminoquinoline (I) and furan-2, 3-di-carbaldehyde (II) molecules was performed using density functional theory (DFT) in B3LYP/6-311G++ (d, p) level of theory and based on the optimized structures, structural parameters, dipole moments, as well as frontier molecular orbitals of the desired bis-Schiff bases (III) were calculated. The statistical thermodynamic functions, i.e., enthalpy changes (ΔHºr = 10.21 kcalmol−1) and Gibbs energy changes (ΔGºr = 12.62 kcalmol−1) were obtained from the theoretical harmonic frequencies (freq keyword). Each of these imines has four geometrical isomers (ZZ, EZ, ZE, and EE), and their relative stability for III-H was studied. It was found that ZZ (III-H) is the most unstable (9.20 kcalmol−1) in four isomers. To check the nonlinear optical (NLO) properties of these organic compounds the first hyperpolarizability (βtotal) and average polarizability (αave) parameters were calculated. All of these bis-Schiff bases (III) have βtotal values larger than the magnitude of the βtotal value for urea (a standard molecule) and III-NO2 is the best NLO material in studied compounds. So for III-NO2, Mulliken atomic charges analysis, frontier orbitals, and molecular electrostatic potential (MEP) surfaces have been studied. [ABSTRACT FROM AUTHOR]

Improving polarizability is an important strategy for designing high‐performance mid‐infrared (mid‐IR) nonlinear optical (NLO) materials. The substitution of equivalent or aliovalent atoms can manipulate the polarizability by adjusting the symmetry of the polyhedron. Herein, the Li+ and Cd2+ are introduced into the Cu3PS4 as the equivalent and aliovalent dopants for the Cu site. As a result, Li+ can significantly improve the bandgap (Eg) of LixCu3−xPS4 from 2.38 to 2.88 eV, leading to a higher laser‐induced damage threshold (LIDT) of 4.9 times than AgGaS2 (AGS) with a comparable second harmonic generation (SHG) response of AGS (26−45 µm). Interestingly, Cd2+ can improve the SHG response and enlarge the Eg simultaneously. As a result, Cd0.4Cu2.2PS4 has a large SHG response of 10 × AGS at 2050 nm (26−45 µm) and a LIDT of 2.6 × AGS. Theoretical calculations reveal that lattice vacancies induced by Cd2+ significantly boost polarizability compared to LixCu3−xPS4 with no vacancy, leading to a strong NLO response. [ABSTRACT FROM AUTHOR]

Improving polarizability is an important strategy for designing high‐performance mid‐infrared (mid‐IR) nonlinear optical (NLO) materials. The substitution of equivalent or aliovalent atoms can manipulate the polarizability by adjusting the symmetry of the polyhedron. Herein, the Li+ and Cd2+ are introduced into the Cu3PS4 as the equivalent and aliovalent dopants for the Cu site. As a result, Li+ can significantly improve the bandgap (Eg) of LixCu3−xPS4 from 2.38 to 2.88 eV, leading to a higher laser‐induced damage threshold (LIDT) of 4.9 times than AgGaS2 (AGS) with a comparable second harmonic generation (SHG) response of AGS (26−45 µm). Interestingly, Cd2+ can improve the SHG response and enlarge the Eg simultaneously. As a result, Cd0.4Cu2.2PS4 has a large SHG response of 10 × AGS at 2050 nm (26−45 µm) and a LIDT of 2.6 × AGS. Theoretical calculations reveal that lattice vacancies induced by Cd2+ significantly boost polarizability compared to LixCu3−xPS4 with no vacancy, leading to a strong NLO response. [ABSTRACT FROM AUTHOR]

Achieving a quick temperature increase is a burning issue for biophysical applications, like germ inactivation and tumor ablation, and for energy performances, like solar collectors and steam generators. Based on the plasmon resonance phenomenon, noble metallic nanoparticles have emerged as promising weapons due to their very high biocompatibility, optical properties, and high surface-to-volume ratio, increasing energy conversion and allowing the maximum temperature to be reached faster. This work examines the energy conversion in sandwiched glassy platforms with gold nanorods. The platforms are kept vertically in the air and illuminated by a 0.5 W near-infrared laser (808 nm). To describe this aspect theoretically, the size and conversion efficiency of the electromagnetic properties are compromised between the proposed model and the stability of the nanorods. As a research approach, our model of cross-sections and polarizability for the surface effect is proposed, coupled with classical CFD numerical calculations. The results of the proposed model, validated by a thermal camera and spectroscopy measurements, indicate that as long as the energy conversion is visible with relatively low-power lasers (ΔT = 18.5 °C), the platforms do not offer fast heat dissipation. The results indicate that, despite the flow forcing by the air inflow, the entropy generation due to heat conduction is more than three orders higher than the dynamic entropy production. Flow forcing corresponds to the value of the velocity for classical convective motions. Therefore, the delivered heat flux must be distributed via convective transport or the associated high-conductive materials. [ABSTRACT FROM AUTHOR]

A suite of measurements of refractive index n (p , T 90) is reported for gas phase ordinary water H 2 O and heavy water D 2 O. The methodology is optical refractive index gas metrology, operating at laser wavelength 633 nm and covering the range (293 < T 90 < 433) K and p < 2 kPa . A key output of the work is the determination of molar polarizabilities A R = 3.7466 (18) · [ 1 + 1.5 (6) × 10 - 6 (T / K - 303) ] cm 3 · mol - 1 for ordinary water, and A R = 3.7135 (18) · [ 1 + 4.4 (10) × 10 - 6 (T / K - 303) ] cm 3 · mol - 1 for heavy water, with the numbers in parentheses expressing standard uncertainty. For heavy water, this work appears to be only the second gas phase measurement to date. For both ordinary and heavy water, this work agrees within 0.15 % with recent ab initio theoretical results for A R , but the comparison is affected by imperfect knowledge of dispersion. For ordinary water, the close agreement between the present work and theory suggests problems at the 2 % level in the low density limit of the reference formulation for refractivity. [ABSTRACT FROM AUTHOR]

The current study reports tailoring the electronic donor structures of organic dyes to modify their optical and nonlinear optical (NLO) response properties. Five (5) tri‐phenyl amine (TPA) based Donor‐π‐Acceptor (D‐π‐A) organic dyes with the codes ICAA1, ICAA2, ICAA3, ICAA4, and ICAA5 were designed and investigated for their optical and NLO properties using quantum chemical methods. Optical and NLO properties of these dyes were studied by CAM‐B3LYP method and 6‐311G* basis set. The focus has been on the impact of adding secondary donors and shifting their substitutions at ortho (o), meta (m) and para (p) positions. Among all designed compounds, ICAA4 showed the highest amplitude of average third‐order NLO polarizability <γ>, which is calculated to be 1316 × 10−36 esu. Time‐dependent Density Functional Theory (TD‐DFT) method was used to determine how a change in the position of the donor affected the excitation energy (Eg) and NLO response properties. The findings showed that changing the position of the secondary donor results in a red shift among absorption spectra as well as the increase in their NLO responses. Complete process of intramolecular charge transfer (ICT) has been investigated in terms of different optical parameters such as frontier molecular orbitals (FMOs), molecular electrostatic potentials (MEPs), transition density matrix (TDMs), density of states (DOS), electron density difference (EDD), and natural bond orbital (NBO) analysis. Our calculations for study of ICT process indicate that p‐position of methoxy group performs better among all other positions and even it has better NLO response properties than the compound with three collective methoxy groups. The calculated Voc values of all designed molecules range from 1.09 to 1.30, all of them are positive while their ΔGinject is found to be in the range of −0.87 to −1.79 eV indicating their decent potential for photovoltaic applications. The studied optical, NLO and photovoltaic parameters illustrated that ICAA1 to ICAA5 are appropriate molecules not only for NLO applications but also for efficient photovoltaic purposes. [ABSTRACT FROM AUTHOR]

The paper considers the problem of choosing the composition, structure, and size of spherical catalyst nanoparticles for carrying out plasmon-induced polymerization reactions. The concept of reducing the activation energy of the reaction in the presence of a catalyst and, accordingly, increasing the rate of a chemical reaction during heating due to the excitation of surface plasmon resonance is presented. Using the Drude model for the dielectric function, relationships were obtained for the frequency dependences of such characteristics as the real and imaginary parts of the polarizability, heating and the rate of chemical reactions when monometallic and bimetallic nanoparticles are used as catalysts, as well as the amplification of fields in their vicinity. The concepts developed in this work take into account the classical size dependence of the effective electron relaxation rate in monometallic and bimetallic nanoparticles under the assumption of diffuse scattering of electrons. Changes in the positions of the maxima of the imaginary part of the polarizability, heating, and reaction rate are analyzed with a change in the radii of monometallic and bimetallic nanoparticles. It is shown that the maxima of the dependences under study correspond to dipole surface plasmon resonances, and their number depends on the particle morphology. Changes in the amplification of electric fields in the vicinity of nanoparticles of different morphology have been studied. It has been found that the enhancement of the fields in all considered cases is maximum on the surface of the nanoparticle and decreases with distance from it. Practical recommendations are formulated regarding the size, composition and structure of nanoparticles for plasmon catalysis, which provide the highest rates of chemical reactions. Thus, all obtained frequency dependences have one maximum for monometallic and two maxima for bimetallic nanoparticles. [ABSTRACT FROM AUTHOR]

Earlier experimental works report the synthesis of zwitterions with anionic p-dicyanomethanide (coupled to benzene and thiophene) donors. In this report, four such zwitterions (two metameric pairs) are investigated using HF, B3LYP, CAM-B3LYP, HSE06, and raB97xD methodologies. This work is focused on (1) metameric (Reichardt's and Brooker's) induced conformational selectivity (twisted vs. planar) and (2) efficiency assessments of benzene- versus thiophene-based anionic donors. These effects were found to have significant influences on many tensorial and nontensorial properties. For Reichardt's type, large twisting was observed for the benzene case and lower twisting for the thiophene case. Enhanced first hyperpolarizability were observed for Reichardt's type (257.2 x 10-30 esu) than Brooker's type (67.2 x 10-30 esu), thus indicating the former type to be more efficient (approximately fourfold enhancement) chromophore (approximately seven-time enhancement for thiophene-based systems). Similarly, between the benzene versus thiophene cases, enhanced hyperpolarizabilities were observed for the former (257.2 x 10-30 esu) than the latter type (112.0 x 10-30 esu), indicating the benzene type as more efficient (more than twofold enhancement) donor (approximately four-time enhancement for Brooker's types). The structure-property manipulations strategies investigated here can be used as valuable tools in the designing of efficient functional molecular materials for various fundamental applications. [ABSTRACT FROM AUTHOR]

Most geophysical and geochemical data are commonly acknowledged to exhibit fractal and multifractal properties, but the fractal characteristics of polarizability have received limited attention from the literature. The present study demonstrates that the polarizability data of the graphite deposits have fractal characteristics and introduces the fractal method for its quantitative analysis to indicate and predict the properties of graphite deposits. The results show that the concentration-area (C-A) method is superior to classical interpolation in anomaly extraction but inferior to the spectrum-area (S-A) method in the coverage region. Because the type of graphite ore is sedimentary-metamorphic in this area, the graphite ore-bodies can be regarded as a special stratum, which is different from most metal deposits, and the anomaly of graphite ore are shown in the background mode of the S-A method. The high values of the background mode effectively indicate the potential areas where the graphite-bearing strata occur, while observing a decrease in the power-law exponent (β) of the background mode as the width of ore-bodies increases. The validity of this conclusion was confirmed based on the vertical profiles of the predicted area, and the uncharted ore vein was thereby identified. Furthermore, it was found that the anomaly mode can serve as a grade indicator of graphite ore rather than delineating the fault. By integrating the background and anomaly modes of the S-A method, we can quantitatively predict and effectively identify high-grade targets from sedimentary deposits containing minerals in future exploration. [ABSTRACT FROM AUTHOR]

This paper presents a novel low-cost phosphate glass preparation by using the melt quenching technique. It was investigated for use in diagnostic protective applications. The range of UV-VIS wavelength is used to estimate the optical energy gap. The MAC denotes the mass attenuation coefficients of the present glass were computed at low photon energies between 15 and 200 KeV using the MIKE program. The manufactured glasses parameters viz; the mean free path, half value layer, tenth value layer, effective atomic number, effective electron density, and linear attenuation coefficient denotes as follows; MFP, HVL, TVL, Zeff, Neff and LAC were determined. Furthermore, the molar volume, oxygen molar volume, and optical packing density of fabricated glass were assessed. The third-order susceptibility (χ(3) and non-linear refractive index of the present glass were determined. From previous results, it can be concluded that the glass has unique attenuation characteristics, therefore, can be used for radiation protection at low energy 15 to 200 KeV. [ABSTRACT FROM AUTHOR]

To overcome the energy limitations of conventional Li‐ion batteries (LIB), renewed attention has been given to Li‐metal anodes, which provide the highest capacity and lowest anode potential. To realize Li‐metal batteries (LMBs), it is crucial to stabilize unwanted side reactions on the surface and to inhibit problematic dendrite growth, which causes short‐circuit issues. Herein, diverse pyrrolidone‐based molecular dipole additives controlled by different functional groups are introduced as trifunctional surface stabilizers. It is discovered that the Li–Li symmetric cell improves proportionally with the molar volume and corresponding polarizability values of the molecular dipoles. The highly polarizable pyrrolidone‐based molecular dipoles offer exceptional benefits, including surface flattening of the Li metal anode, controlling the growth direction of crystalline Li, and forming durable solid electrolyte interface (SEI) components. The study is based on polarizability‐controlled molecular dipoles, and offers an effective approach for designing advanced surface stabilizers to develop of high‐performance LMBs.

Catalan’s SPPN, a measure of solvent polarity/polarizability has been analysed in terms of molecular properties derived from computational chemistry. The results show that SPPN correlates positively with the molecular dipole moment and quadrupolar amplitude and negatively with the molecular polarizability. These correlations are shared with Kamet and Taft’s π* and Reichardt and Dimroth’s ET(30). Thus, one can associate the solvent polarity with non-specific interactions involving the permanent charges on solvent molecules. It is also noted that the opposite correlations, all three parameters increasing with increasing solvent polarity but decreasing with increasing solvent polarizability, creates an ambiguity in their use, for example, in linear free energy relationships.

Determining absolute electron impact ionization cross-sections for atoms and molecules, whether through experimental or theoretical means, poses a formidable challenge and is typically limited to a narrow selection of species. In this paper, by using measured cross-sections and polarizability data, it was obtained empirical scaling laws for total single ionization and non-dissociative single ionization cross-section maximum of neutral molecules by collisions with electrons. It is found that the total single ionization cross-sections scale linearly with the target electric static polarizability, while the non-dissociate cross-sections exhibit a saturation effect for large target polarizabilities. This saturation effect is interpreted as the increasing role of fragmentation with polarizability. [ABSTRACT FROM AUTHOR]

Catalan's SPPN, a measure of solvent polarity/polarizability has been analysed in terms of molecular properties derived from computational chemistry. The results show that SPPN correlates positively with the molecular dipole moment and quadrupolar amplitude and negatively with the molecular polarizability. These correlations are shared with Kamet and Taft's π* and Reichardt and Dimroth's ET(30). Thus, one can associate the solvent polarity with non-specific interactions involving the permanent charges on solvent molecules. It is also noted that the opposite correlations, all three parameters increasing with increasing solvent polarity but decreasing with increasing solvent polarizability, creates an ambiguity in their use, for example, in linear free energy relationships. [ABSTRACT FROM AUTHOR]

The electrical and non-linear optical characteristics of 1-dodecyl 3-methyl-imidazolium chloride (C12MIM.Cl or DDMIM.Cl) and 1-dodecyl 3-methyl-imidazolium bromide (C12MIM.Br or DDMIM.Br) ionic liquid crystals for optoelectronic devices were investigated in this study utilising B3LYP method and 6-311++G(d,p) basis set with Gaussian09 software. The majority of ionic liquid crystal research to date has been experiment-driven, with very few theoretical studies on the material's optical characteristics. Additional understanding of the behaviour of ionic liquid crystals is revealed through molecular spectroscopic research. The electronic properties (molecular energy band gap, electrostatic potential map and HOMO–LUMO orbitals) and spectroscopic (IR, UV) characteristics were assessed with the aid of a theoretical/computational model at B3LYP/6-311++G(d,p), whereas a nonlinear optical (NLO) study was carried out using the B3LYP and M06-2X methods with 6-31G(d) and 6-311++G(d,p) basis sets. Results demonstrate reasonable nonlinear optical characteristics in these molecules. [ABSTRACT FROM AUTHOR]

In this article, we have investigated an electron energy spectrum, optical absorption coefficients (OACs) and polarizability under the effect of the co-directed electric and magnetic fields in the multilayer spherical quantum antidot (MSQAD) Al0.3 Ga0.7 As/GaAs/Al0.3Ga0.7 As with off-center impurity. The calculations were done for different dot sizes within the effective mass approximation using the matrix method. The dependence of the total, linear, and nonlinear OACs on the incident photon energy is calculated considering the intraband electron quantum transitions. The donor polarizability and impurity binding energy as function of electric field intensity are obtained at different values of the magnetic field induction. [ABSTRACT FROM AUTHOR]

Globally, unconventional hydrocarbons, known for the symbiosis of their hydrocarbon source and reservoir, pose significant seismic exploration challenges due to their confined target regions, extensive burial depth, minimal acoustic impedance variation, marked heterogeneity, and strong anisotropy. Over the past decade, electromagnetic (EM) exploration has evolved markedly, improving resolution and reliability, thus becoming indispensable in unconventional hydrocarbon exploration. Focusing on China's application of the controlled source electromagnetic method (CSEM), this review examines the geological and electrical attributes of these reservoirs, notably the low resistivity, high polarization and strong electrical anisotropy of shale gas reservoirs. Despite the demonstrated positive correlation between induced polarization (IP) parameters and reservoir parameters, current methodologies emphasize the IP effect, inadvertently neglecting electrical anisotropy, which affects data precision. Moreover, single-source CSEM methodologies limit the observational components, acquisition density, and exploration area, impacting the accuracy and efficacy of data interpretation. Recently developed CSEM techniques in China, namely wide-frequency electromagnetic method (WFEM), time–frequency electromagnetic method (TFEM), long offset transient electromagnetic method (LOTEM), and wireless electromagnetic method (WEM), harness high-power pseudo-random binary sequence (PRBS) waveforms, reference observation and processing technology, hybrid inversion, and enhancing operational efficiency and adaptability despite the pressing need for multi-functional software for data acquisition. Case studies detail these methods' applications in shale gas sweet spot detection and continuous hydraulic fracturing monitoring, highlighting the immense potential of EM methods in unconventional hydrocarbon sweet spot detection and total organic content (TOC) predication. However, challenges persist in suppressing EM noise, streamlining 3D inversion processes, and improving the detection and evaluation of sweet spots. [ABSTRACT FROM AUTHOR]

This article studies the electrostatic response of a two-dimensional dielectric half-ellipse. A semianalytical method is presented for solving the polarizability of a half-ellipse as a function of its relative permittivity. The polarizability depends on the direction of incident field, and therefore, it is written as a dyadic with two perpendicular components. These are called series and parallel polarizability, and they are solved separately. The solution requires a series expansion of the potential function, and the coefficients must be obtained numerically, through an inversion of a finite matrix equation. Numerical results are presented for the polarizability components of the half-ellipse as functions of its geometry and permittivity. [ABSTRACT FROM AUTHOR]

An investigation of electro‐optical and nonlinear optical properties of pure and halogenated (−Cl, −Br) hexahexyloxytriphenylene (HAT6) molecule is presented employing a density functional theory (DFT) approach. The effect of halogenation on HAT6 molecule is studied by introducing single and double halogens (Cl, Br) in its molecular geometry. The geometries are optimized progressively to achieve stability using B3LYP method with 6‐311 basis sets. The physical properties encompassing electro‐optical, thermodynamic, and electronic properties of single molecule of HAT6 are computed using DFT method. The introduction of halogens to discotic HAT6 molecule to an augmentation in molecular polarizability, rendering halogenated HAT6 a suitable candidate for nonlinear optical devices due to its π–π conjugation and improved optical parameters. The UV‐Vis spectra indicate the predominant absorptions and changes in absorption depend on the halogenations of the HAT6 molecule. Also, the halogenation effect leads to a significant reduction in the energy bandgap directly associated with electron‐electron correlation, facilitating straightforward tuning. [ABSTRACT FROM AUTHOR]

A series of zwitterions with varying bridges, connecting N‐methyl pyridinium acceptor, with phenolate donor, are investigated using various methodologies like, HF, B3LYP, CAM‐B3LYP and ωB97xD. In this systematic study effects of various mono aromatic rings as bridges, on the response properties like, the dipole moments (μ), polarizabilities (α), hyperpolarizabilities (β) and adiabatic absorptions were analyzed using CPHF and TDDFT (or TDHF) theories. Compared to many traditional bridges, as well as without a bridge, enhanced nonlinear optical (2ND order NLO) responses were observed for these aromatically bridged zwitterions (with benzene ring as bridge ~5.3 times and ~7.9 times enhanced hyperpolarizabilities were observed compared to either the ethylene bridge or without any bridge cases, respectively). Also, many significant differences and large enhancements in response properties were observed compared to our earlier works on non‐zwitterionic system (~4.3 times enhanced hyperpolarizability—benzene as bridge case). For some bridge cases, 10‐ to 15‐fold enhanced hyperpolarizabilities were observed compared to without any bridge case. This work reports a class of non‐TICT chromophores, promoting bridge aromaticity control on structure–property correlation, as a suitable and efficient chromophore design strategy to create a wide range of function molecular chromophores. Also, unidirectional natures of response properties and large dipole moments can make these zwitterions suitable 1D‐molecular materials for various contemporary technological applications, as poled polymer‐based materials. [ABSTRACT FROM AUTHOR]

This contribution reports the structure–property correlations for few already synthesized bi‐aryl types of zwitterionic molecules. Quantum mechanical methodologies like, HF, MP2, B3LYP, CAM‐B3LYP, LC‐ωPBE, M06‐2X, and ωB97xD were used to investigate the optoelectronic properties of some interesting metameric pairs, where the molecules were bonded either through Reichardt's or Brooker's modes. Different bonding modes and inter‐ring attractive forces are assigned to investigate three distinct cases (i) metameric enforcements & preferential resonance stabilizations, (ii) inter‐ring hydrogen bonded stabilizations through hetero‐atoms in the ring, and (iii) an amalgamation of these two forces. Computations indicate unusual structural preferences (planar vs. twisted) by the metameric pairs, and thus direct reflections of these behaviors on some of the important tensorial properties like, dipole moments, polarizabilities, hyperpolarizabilities, and so forth were observed. The metameric manipulation on structure–property correlations shown by these molecules can be utilized as useful strategies for efficient chromophore design, not only in the field of nonlinear optics, but also in other areas of research connecting to advanced functional materials for technological applications. [ABSTRACT FROM AUTHOR]

The solvatochromic properties of important sulfa drug molecules sulfadiazine (SDZ), sulfamerazine (SMZ) and sulfamethazine (STZ) were investigated in solvents of different polarities, including their solvation in a binary THF-Water solvent mixture. Steady-state absorption and fluorescence methods were utilized to analyse the absorption and fluorescence spectra of these compounds, which reveals the significant spectral shifts corresponding to changes in solvent polarity. Further insights on the solvatochromic characteristics of the examined drug molecules were obtained using Lippert-Mataga, Reichardt’s, Kamlet-Taft, and Catalan’s solvent polarity approaches. The study also identified synergistic effects in the THF-Water solvent mixture. Different solvatochromic techniques were employed to calculate the excited-state dipole moment of the studied molecules. The Bilot-Kawaski approach was utilized to investigate the influence of solute polarizability on the excited state dipole moment and the change in dipole moment. [ABSTRACT FROM AUTHOR]

The optical properties of rod-like two-layer nanoparticles are studied using the notions of equivalent prolate spheroid. The calculations are presented for frequency dependencies for polarizability and the absorption and scattering cross-section of prolate spheroids, cylinders, and spherocylinders. The effect of the sizes, the shapes of the nanoparticle and the material of the core and the shell on the location of the maxima of the imaginary part of polarizability and absorption and scattering cross-sections is analysed. The recommendations regarding the shape and size ratio of the nanoparticles for obtaining the maximum value of radiation efficiency are formulated.

The molecular properties of a biphenyl benzoate based ferroelectric liquid crystal compound were estimated using DFT/6-31G method. Non Linear Optical properties of the compound have been estimated by calculating its polarizability and hyperpolarizability. Frontier molecular orbital (FMO), Molecular electrostatic potential (MEP) and Infrared (IR) spectra have been simulated. Global parameter and a few thermodynamic parameters have also been calculated. The phase sequence has been confirmed by polarizing optical microscopy. The spontaneous polarization and rotational viscosity of the compound have been measured. From results the efficacy of the compound in NLO or electro optical applications have been inferred. [ABSTRACT FROM AUTHOR]

An n (p , T 90) measurement suite is reported for the gases helium, argon, and nitrogen. The methodology is optical refractive-index gas metrology, operating at laser wavelength 633 nm and covering the temperature range (293 < T < 433) K and pressures p < 0.5 MPa . The measurement suite produces several things of thermophysical interest. First, the helium dataset deduces the effective compressibility of the apparatus with a relative standard uncertainty of 1.3 × 10 - 4 . Next, the argon dataset determines T - T 90 with a relative standard uncertainty of about 3 μ K · K - 1 . (The implementation is relative primary thermometry; T - T 90 is the difference between thermodynamic temperature and ITS-90.) Finally, the nitrogen dataset estimates the temperature dependence of polarizability within 3.5 % relative standard uncertainty. As a by-product of the nitrogen and argon measurements, values of the second density virial coefficient B ρ (T) are derived with uncertainties smaller than those of previous experiments. More broadly, the work enables conversion of a measured refractivity at known temperature to optical pressure within 3.5 μ Pa · Pa - 1 across the stated range, albeit traceable to the diameter of a piston-gage. [ABSTRACT FROM AUTHOR]

Theoretical study of the photophysical/photochemical properties of 1H‐benzimidazole and its derivatives was carried out using APFD, B3LYP, CAM‐B3LYP and PBE0 density functionals with 6‐311+G(2d,p) basis set. The effects of ethanol, 1,4‐dioxane, acetonitrile and water was investigated by means of Integral Equation Formalism of the Polarizable Continuum Model (IEPCM) in the framework of Self‐Consistent Reaction Field (SCRF). The results obtained show that S2 state of the 1H‐benzimidazole molecule is more acidic than the S0 state as the N5−H11 bond length increased to ~ 1.01 Å. At B3LYP/6‐311+G(2d,p) level of theory, the excitation energy of 1H‐bensimidazole molecule in ethanol from S0 to the S2 state was calculated to be 273 nm (4.54 eV). The electronic energy for this transition was calculated to be 0.131 a.u. and observed to occur between π→π* orbitals. Calculations with the PBE0, APFD and B3LYP functionals reproduced the experimental dipole moment in 1,4‐dioxane, with values of 4.09, 4.09 and 4.07 Debye respectively. However, the dipole moments of the 2‐ethyl‐7‐nitro‐5‐substituted‐1H‐benzimidazoles were calculated to be higher for electron donating groups (EDGs) than those bearing electron withdrawing groups (EWGs). In addition, the molecular polarizability was observed to increase with decreasing energy gap. Local excitation (LE) and charge‐transfer (CT) were observed to mediate the mechanisms of electronic excitation in 2‐ethyl‐7‐nitro‐5‐substituted‐1H‐benzimidazoles. [ABSTRACT FROM AUTHOR]

The influence solvents from different polarity and hydrogen bonding ability on electronic absorption spectrum of Methylene blue was investigated. The visible absorption spectra were recorded in eleven neat solvents in the range 400–700 nm. Methylene blue has two absorption maxima, the first band assigned to n-π* from amino groups and the second band assigned to weakly forbidden n-π* transition with charge transfer. The charge transfer band of Methylene blue showed red shift with increasing the relative permittivity of neat solvents. The red shift in wavelength(λmax) for the charge transfer band of Methylene blue was observed when proceeding from dioxane (λmax = 650 nm) into methanol (λmax = 655 nm) into cyclohexanone (λmax = 660 nm) into dimethylsulfoxide (λmax = 665 nm) as well as water (λmax = 665 nm), this shift not agree with the polarity of solvents but due to combination of several parameters. The absorption of charge transfer band in methanol and ethanol as hydrogen bonding donating solvents (HBD) showed the highest intensity than the absorption band in dimethylsulfoxide and dimethylformamide as hydrogen bonding accepting solvents (HBA) due to non-electrostatic interaction between the amino groups and solvents. The charge transfer band in neat solvents were correlated with several parameters using linear solvation energy relationships. The results showed that electrostatic interactions of the solvents play an important role in the shift of absorption maxima of Methylene blue in neat solvents. The acidity constants (pKa) of Methylene blue were estimated by using absorbance measurements in different media. The acidity constants (pKa) values of Methylene blue were affected by cosolvent, which the pKa values increasing in the order propanol < methanol < dioxane, this order not agreement with increasing the relative permittivity of the medium. [ABSTRACT FROM AUTHOR]

New conception of spin‐tautomery was developed based on the results of quantum chemical investigation of the endohedral Y@C60 complex. The embedding energies of yttrium into the fullerene cavity, dipole moments, polarizabilities, and IR spectra in the doublet and quartet spin states were calculated by the density‐functional theory quantum chemical methods. The degeneracy degree of the state of the complex is retained upon doublet–quartet excitation, since a twofold increase in the number of electron spin projections is compensated by a twofold decrease in the number of equivalent potential energy minima. The non‐conservation of spin by an endohedral complex with a heavy atom makes it possible to interpret the interconversion of doublet and quartet states as a non‐degenerate spin‐tautomery. [ABSTRACT FROM AUTHOR]

The relations for the polarizability of the metallic nanoparticles, coated with the shell of cyanine dyes, are obtained in the article. The frequency dependencies for light absorption and scattering efficiencies, the heating of the composite nanoparticle and the electric field amplification in its neighborhood are studied. It is established that all the dependencies have three maxima which correspond to the frequencies of hybrid plasmon-exciton resonance. It is shown that an increase in content of metal in the nanoparticle causes a blue shift of the maxima from the visible part of the spectrum and a red shift of the maximum from ultraviolet frequency range. The issue of application of metal-organic nanoparticles in nanomedicine, in particular for the photothermal therapy of malignant neoplasms is studied. [ABSTRACT FROM AUTHOR]

Context: To comprehend the microscopic property alterations within the ConMoS cluster (n=1–5), this study investigates its internal interactions, electronic characteristics, and orbital correlations employing density functional theory. Structural optimization and theoretical analysis of the cluster are conducted using the Gaussian09 software package, considering various spin multiplicities and employing the B3LYP/def2tzvp quantum chemical method as the computational standard. The outcomes reveal the optimization of the cluster, resulting in 21 stable configurations while continually acquiring energy from the external environment. Analysis of the interaction region indicator functions, the independent gradient model based on Hirshfeld partition, the localized orbital indicator functions, and the electron localization function reveals a trend toward chemical bonding interactions within the interatomic interaction regions. Moreover, the interatomic forces exhibit a high likelihood of engaging in covalent bonding interactions. Both Co and Mo atoms display greater electron delocalization, facilitating the exchange of electrons with the external environment. The paper discuss electron space range, hardness and softness, polarizability, dipole moment, Mulliken population analysis, density of states, HOMO-LUMO diagram, and UV-Vis spectra. Configuration 5a exhibits the broadest electron delocalization and the highest reactivity. It maintains structural stability in external conditions and displays the most polarized molecules. Metal atoms in this cluster exhibit superior mobility compared to non-metal atoms. We elucidate the electron density aggregation region within the cluster. Configuration 1a demonstrates the highest correlation with molar absorption coefficient for its peak. Analyzing the HOMO and LUMO orbital delocalization index and center-of-mass distances revealed that the front orbits of configuration 5a exhibited a broad distribution in space and the minimum center-of-mass distance. Methods: This study presents a theoretical investigation of Co-Mo-S clusters employing density functional theory (DFT). DFT is a prevalent method for exploring the electronic structure and characteristics of atoms, molecules, and solids. The paper examines cluster attributes encompassing interatomic interactions, electronic properties, and frontier orbitals. Gaussian09 software is employed for optimizing cluster structures, while the analysis is augmented using Multiwfn wave function analysis software. By harnessing these theoretical and computational tools, it aims to delve deeper into cluster properties, yielding valuable insights. [ABSTRACT FROM AUTHOR]

The theoretical investigation results of quinoxaline-1, 4-dioxide (I), and some of its derivatives (II-VII) were reported in this paper. Quantum chemical calculations were performed on seven molecules at ab initio/RHF/6–311++G (d, p) and DFT/B3LYP/6–311++G (d, p) levels of theory. Calculated optimized molecular structures, dipole moments, polarizabilities, and first order hyperpolarizabilities for all molecules were dedicated. Also, the frontier molecular orbitals (FMOs), EHOMO (the highest occupied molecular orbital energy), ELUMO (the lowest unoccupied molecular orbital energy), HOMO-LUMO energy gap (ΔE), quantum chemical parameters such as chemical potential (Pi), absolute electronegativity (χ), chemical hardness (η), global softness (S), and global electrophilicity (ω) are investigated. 1HNMR spectrum for quinoxaline-1, 4-dioxide (I) was calculated and compared with experimental data. The results of two theoretical methods have been analyzed using the Excel program in the linear regression method.

Achieving a quick temperature increase is a burning issue for biophysical applications, like germ inactivation and tumor ablation, and for energy performances, like solar collectors and steam generators. Based on the plasmon resonance phenomenon, noble metallic nanoparticles have emerged as promising weapons due to their very high biocompatibility, optical properties, and high surface-to-volume ratio, increasing energy conversion and allowing the maximum temperature to be reached faster. This work examines the energy conversion in sandwiched glassy platforms with gold nanorods. The platforms are kept vertically in the air and illuminated by a 0.5 W near-infrared laser (808 nm). To describe this aspect theoretically, the size and conversion efficiency of the electromagnetic properties are compromised between the proposed model and the stability of the nanorods. As a research approach, our model of cross-sections and polarizability for the surface effect is proposed, coupled with classical CFD numerical calculations. The results of the proposed model, validated by a thermal camera and spectroscopy measurements, indicate that as long as the energy conversion is visible with relatively low-power lasers (ΔT = 18.5 °C), the platforms do not offer fast heat dissipation. The results indicate that, despite the flow forcing by the air inflow, the entropy generation due to heat conduction is more than three orders higher than the dynamic entropy production. Flow forcing corresponds to the value of the velocity for classical convective motions. Therefore, the delivered heat flux must be distributed via convective transport or the associated high-conductive materials.

In this paper analyzes the electromagnetic radiation absorption by a composite based on bimetallic nanowires. Using the Drude-Lorentz theory it was obtained the relationship for the polarizability frequency dependences, as well as real and imaginary parts of the dielectric function of layered 1D-systems was obtained. It is shown that the structure in the form of a metal core covered with a layer of another metal leads to splitting and the appearance of two maxima in the frequency dependence of the absorption coefficient. The magnitude and position of the maxima are determined by the composition of bimetallic nanowires and the volume content of metals. The influence of the dimensionality of the systems has been established by comparing the frequency dependences of the composite absorption coefficient based on bimetallic nanowires and nanoparticles. Calculations were performed for Ag@Au and Au@Ag nanowires immersed in Teflon.