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The thermally bistable behavior of spin-crossover solids opens up prospects for their widespread use as information technology materials, sensors, or micro-refrigerators. In this paper, we build upon a mean-field model of spin-crossover transition in elastic Morse lattice. The phase transition caused by the short-range elastic intermolecular interaction is discussed using an Ising-like fictitious-spin formulation and mean-field theory. [ABSTRACT FROM AUTHOR]

Three Imines (H2L1-H2L3) were designed, synthesized, and examined the molecular docking with SARS-CoV-2 Mpro (PDB ID: 6LU7 & 7LKD). The molecular docking results reveals that the imines (H2L1-H2L3) with 6LU7 protein of SARS-CoV-2 virus exhibited the binding affinity (ΔG) of −6.0, −6.4, and −6.8 kcal/mol with good inhibition constant (Ki) of 4.113, 4.237, and 4.239 µM, respectively. The docking results of the imines (H2L1-H2L3) with 7LKD also resulted binding affinity (ΔG) of −7.3, −7.8, and −7.5 kcal/mol with good inhibition constant (Ki) of 4.459, 4.897, and 5.638 µM, respectively. The molecular docking analysis predicted that the imines (H2L1-H2L3) may be used as anti-SARS-CoV-2 virus. [ABSTRACT FROM AUTHOR]

A new class of λ-shaped azo materials with a cinnamate linkage group has been designed, synthesized, and well-characterized. Further, the liquid crystalline property has been studied by using POM and DSC analysis. Out of six derivatives, five compounds displayed liquid crystalline properties. The liquid crystalline property is observed in an enantiotropic manner. The structure–property relationship is further studied for the understanding of the exhibition of liquid crystalline properties. The results showed that their liquid crystalline phase behavior was closely related to the number of mesogenic units, rigidity, and flexibility of the molecular systems. [ABSTRACT FROM AUTHOR]

Molecular asymmetric imprinting polymerization in the cholesteric liquid crystal was carried out. An L-isoleucine derivative with fluorine was synthesized for a chiral inducer to induce the cholesteric liquid crystal from the nematic liquid crystal. A substance with multiple asymmetric centers can be obtained conveniently to use amino acid as chiral substance. The L-isoleucine derivative induced helical structure for 4-cyano-4'-hexylbiphenyl (6CB). Electrochemical preparation of π-conjugated polymers was carried out in the cholesteric liquid crystal. Fingerprint texture derived from the cholesteric liquid crystal was transcribed to the polymers. UV-vis and circular dichroism (CD) spectra of oxidized (doped) for and reduced (dedoped) form of the polymer were measured. Electrochemical polymerization in the helical liquid crystal produced the molecular aggregation imprinted chiral polymers, which have liquid crystal-like aggregation form, chirality with no stereogenic center via formation of polymer atropisomer, and electrochemical driven change in optical activity, as a form of electro-optically coloration active polymers. Finally, the polarons and bipolarons are in the form of chiral structure. These charge carriers in the polymers can be determined as chiral charge carrier "chiralions". [ABSTRACT FROM AUTHOR]

A new triazoline-quinazolinone compound, 1-cyclopropyl-3-(3-((1-(2- methoxyphenyl)-5-oxo-[1, 2, 4]triazolo[4,3-a]quinazoline-4(5H)-yl)methyl)phenylurea, was attained by nine steps and selected the method of inverse synthetic analysis. Meanwhile, the structure of the title compound was not only certified by MS, 1H NMR, FT-IR, and 13C NMR spectroscopy, but the compound's single crystal was measured by X-ray diffraction. The optimized molecular crystal structure was ulteriorly determined using density functional theory (DFT), and it was compared with the value of X-ray diffraction. Furthermore, through more deeply studies by means of the molecular electrostatic potential and frontier molecular orbitals (FMOs) of compound 1, more physicochemical properties were investigated. [ABSTRACT FROM AUTHOR]

Spectral properties of polymer macromolecules in the optical energy range and relation of these properties to the chemical structure and energy levels system of polymers were examined. The nature of optical centers of the macromolecules with π-electron systems localized on separate groups (so-called chromophores) was analyzed. It was stressed that such vitally important biopolymers as DNA and RNA belong to this type of polymers. It was shown that in synthetic and biological macromolecules with pendant aromatic groups, the triplet excitons meet and annihilate with the very high probability due to large lifetime and one-dimensional motion. The presented results prove that efficiency of triplet-triplet annihilation processes (at the used excitation power) is higher than efficiencies of other electronic processes. Consideration of this fact in the kinetic equation for triplet excitons in macromolecule leads to inverse square root dependence of phosphorescence intensity on the macromolecule length. At the same time, for three-dimensional molecular crystals of stilbene and para-terphenyl, the intensity of the delayed fluorescence is less dependent on the size of the granules compared to the dependence of the delayed fluorescence intensity on the length for one-dimensional macromolecules. [ABSTRACT FROM AUTHOR]

In this study, the compound 3-(4-(2,4-dimorpholinopyrido[2,3-d]pyrimidin-6-yl)phenyl)-1,1-diethylurea was prepared. The synthesis of the compound was confirmed using 1H NMR, 13C NMR, HRMS and FT-IR spectroscopies. The crystal structure of the title compound was optimized using by density functional theory (DFT) calculations, and the molecular structure of the crystal was compared with theoretical calculations. The results show that the molecular structure optimized by DFT is essentially identical to the crystal structure determined by X-ray single-crystal diffraction. Additionally, the optimal structure and frontier orbital energy were calculated using DFT. [ABSTRACT FROM AUTHOR]

The paper discusses mechanisms of molecular motion in lamellar chain molecular crystals of the stearic acid. Thermal calorimetry, dielectric and IR-spectroscopy methods indicate a phase transition from the orthorhombic crystal phase into the orthorhombic rotator phase in the vicinity of Тrot = 50 °С. This rotator phase allows for the excitation of the topological solitons, which reorient the aliphatic chain by 180° and translate it by one link. These topological solitons form at the terminal methyl groups and, upon propagating along the chain, are reflected from the dimeric ring until their energy is high enough to reorient the dimer. Dissociation of the dimeric rings of the stearic acid takes place later in the melt. [ABSTRACT FROM AUTHOR]

T. N. Govindaiah, Nagappa & H. R. Sreepad (2013) Twisted Grain Boundary Phase in Binary Mixture of Liquid Crystals, Molecular Crystals and Liquid Crystals, 574:1, 1-8. T. N. Govindaiah, H. R. Sreepad & Nagappa (2015) Formation of Lyotropic Micellar Nematic Phase in Binary Mixture of Liquid Crystals, Molecular Crystals and Liquid Crystals, 608:1, 166-173. T. N. Govindaiah, H. R. Sreepad, B. K. Kempegowda & Nagappa (2013) Induced Reentrant Smectic-A Phase in Binary Mixtures of Liquid Crystals, Molecular Crystals and Liquid Crystals, 587:1, 54-59. [Extracted from the article]

The observation of second harmonic generation (SHG) signals, which is forbidden in centrosymmetric crystals, should necessitate clarification of their causes. The authors of a recent paper (Sivaraman et al Molecular crystals & Liquid crystals 656 (2017) 153-168) report to have grown a so-called crystal of diglycine zinc dipicrate which, in fact, is tetraaquabis(glycine)zinc(II) dipicrate dihydrate. This compound despite being centrosymmetric, was reported to exhibit a strong second harmonic response viz. 1.07 times of potassium dihydrogen phosphate. Based on a reinvestigation, we prove that the observation of SHG is due to dehydration of the crystal under laser irradiation. [ABSTRACT FROM AUTHOR]

Built on electron beam shifting effect, the picoscope with resolution of 10 picometers demonstrates fascinating ability to directly visualize the density of electron clouds molecules together with chemical bonds. It results in the appearance of long-awaited visual molecular technologies. Densitometry of electron density is used to show the structure of crystalline graphite with visualization of σ-bonds formed by overlaping the sp2 chemical bonds of carbon atoms, and a system of weak π-bonds that connects the layers of graphite. The article also presents new superdense two-layered diamond-like carbon allotrope, which is proposed to designate rudenite. In the rudenite, each carbon atom forms four strong sp3 chemical bonds as in the structure of diamond, but since the layers are pressed at a distance of 100 picometers, it should have a density of 1.3 times greater than that of diamond. [ABSTRACT FROM AUTHOR]

In recent years, the rekindled interest in B/N ring systems has led to a plethora of novel compounds with varying substitution patterns. Diaminodiboranes are the starting compounds for the preparation of many boron compounds such as diborane derivatives, used for many addition and insertion reactions into multiple bonds in the literature, however there are few air-stable diborane(4) derivatives. In this study, to synthesize new air-stable B,B'-diaryl and bis(dimethylamino)-B,B'-diarylaminodiboranes(4), the bulky amines were selected. These derivatives were prepared through the reaction of lithium anilide derivatives and 1,2-dichlorodiboranes. The structures of the compounds were characterized by using nuclear magnetic resonance (NMR) spectroscopy. The crystal and molecular structures of 3ae, 3af, 3bb, 3be, 3ce, 3cd and 3cf were determined using the single-crystal X-ray diffraction technique. X-ray diffraction studies have showed that the diarylamino group in the solid state is nearly orthogonal to the plane due to the boron-bound bulky groups. [ABSTRACT FROM AUTHOR]

A new complex of diaquabis(5-methoxyindole-2-carboxylato)bis(3-picoline)nickel(II) (Ni(5-MeOI2CA)2(3-pic)2(H2O)2), was synthesized for the first time and characterized by elemental analysis, FT-IR and electronic spectroscopy (UV-Vis) and single-crystal X-ray diffraction (XRD) techniques. The thermal degradation of the Ni(II) complex was investigated using thermogravimetric and differential thermal analyses techniques in oxygen atmosphere. The molecular structure of the complex was determined by single crystal X-ray diffraction technique. Hirshfeld surface analysis (HSA) investigated the packing modes and intermolecular interactions in molecular crystals, as they provide a visual picture of intermolecular interactions. In addition, all computational studies at B3LYP/6-311++G(d,p) were carried out for theoretical characterization of Ni(II) complex. The optimized geometry results, which were well represented the X-ray data, were shown that the chosen of DFT/B3LYP/6-311++G(d,p) was a successful choice for title compound. After a successful optimization, FMOs, chemical activity, non-linear optical properties (NLO), molecular electrostatic potential (MEP), Mulliken population (MPA), natural population analyses (NPA), Fukui function analysis (FFA) and natural bond orbital analysis (NBO), which could not obtained by experimental ways, were calculated and investigated. The computed of net charges and chemical activity studies which helped to identifying the electrophilic/nucleophilic nature. [ABSTRACT FROM AUTHOR]

Polymorphic transitions are typical for molecular crystals of long chain aliphatic compounds. In the present work we studied the possibility of polymorphic transitions via the mechanism of topological solitons. The solitons correspond to stretching/compression of aliphatic chain by a half of the period, accompanied by 180° turn in branched molecules. Triacyglycerides (TAG) were chosen as an object of study; temperature dependencies of the specific heat capacity at constant pressure, complex dielectric permittivity, spectral (IR) and structural (powder XRD) properties of TAGs were characterized performed at −170 ÷ 70°C. Following model was proposed to explain the experimental results. Thermal transformations of TAGs started from initiation of topological solitons on the methyl groups. The solitons passed along the alkyl chains and reoriented the ester groups, resulted in thermal dipole-relaxation polarization defrost observed as a relaxation process in the range (−80÷0)°C. Reaching the stoichiometric obstruction (branching), the solitons reflect from it. When the temperature increases up to 60°C, melting of TAG polycrystals takes place. [ABSTRACT FROM AUTHOR]

The new compound [Li(NO3)(phen)]n (phen: 1,10-phenanthroline) has been synthesized and characterized by elemental analysis, and single crystal X-ray diffraction. The Li+ ion is five coordinated occupied distorted TBP (trigonal bipyramidal) geometry. The Li+ ions are bridged by nitrate anions into 1D polymeric chain. The nitrate anions are coordinated to Li+ ions through chelating and bridging bidentate mode of binding. There are cooperative noncovalent interactions like strong or weak H-bonding, weak π···π and C-H···π interactions are involved to form 2D network. Thermal properties of this complex have been completely described by thermo gravimetric analysis (TGA). Both molecular and crystal structures of this compound were compared and discussed the intermolecular interactions by using Hirshfeld surface analysis and 2D-fingerprint plots. The optimized molecular geometry by DFT calculations agrees closely with obtained from the crystallographic study. Hirshfeld surface analysis of compound (I) indicates that H···H, π···π and C-H···π contacts can account for 30.9, 15.0 and 7.4% respectively of the total Hirshfeld surface area. [ABSTRACT FROM AUTHOR]

In this study, we analyze the influence of image quality for reflected image in the immersive display system composed of two liquid-crystal display (LCD) panels. The evaluation system is set up with curved LCDs with a high curvature ratio of 1500R. Further, the image quality is evaluated at each viewing position. While one panel (A) was fixed, the other panel (B) was measured from the center to 60° along the curved surface. The brightness and color of panel B were measured under the influence of panel A using black and white. The contrast ratio of panel B is 3560:1, but the self-influenced contrast ratio (SICR) considering the influence of panel A was reduced to 483:1. Further, the color index was changed to compare the standard white condition due to light leakage by curvature and reflection from the other panel. [ABSTRACT FROM AUTHOR]

Although polyurethane (PU)- and polysiloxane-based coating agents find wide applications in electronics and automotive industries (e.g., for sealing), their full potential can be realized only based on a deep understanding of property-determining factors. To contribute to this understanding, we synthesized PU resins from polycarbonate diol, poly(tetramethylene glycol), and 4,4-diphenylmethane diisocyanate. The abrasion resistance, modulus, and tensile strength of PU films increased with increasing hard segment content whereas the elongation at break of these films concomitantly decreased. PU-based coating agents were prepared by adding PE wax and other modifiers and their friction coefficients were investigated. A friction coefficient of coating agent was strongly affected by particle size and content of PE waxes. [ABSTRACT FROM AUTHOR]

In this article, a BF2-containg dye was configured and routinely characterized by 1H NMR and MS technology. This BF-cored dye shows intensive emission in chloro-carbon solvents, for example dichloromethane, with the emission peak 475 and 515 nm. The emission profiles almost the mirror image of the absorption of profile. The highly emissive character may ascribe to the coordinate lock, which limited the free rotation of benzene ring and nonradiation transition. Therefore, the dye exhibits highly emissive character. Even if the molecular framework is small, a larger Stoke's shift (170 nm) was observed. Additionally, the emission in film shifts 5 nm more than that in solution. In solid state, the emission maximum reached to 525 nm. In all the case, the emission colors were demonstrated by International Commission on Illumination (CIE) chromaticity system. [ABSTRACT FROM AUTHOR]

To simply prepare hyperbranched polystyrene with dendritic structure for optical and electronic applications, the copper-mediated self-condensing atom transfer radical polymerization of 4-(2-bromopropionyl)oxy styrene has been attempted. Given the unequal reactivity of two propagating species owing to different substituents which stabilize radicals, the influence of polymerization conditions on the structure of dendritic polystyrene were investigated. Higher polymerization temperature leaded to the lower functionality of Br in the branched polystyrene due to HBr elimination. As the catalyst to monomer ratio increased, the degree of branching of the prepared polystyrene was enhanced by increasing the reaction chance of the less stabilized propagating site. [ABSTRACT FROM AUTHOR]

M-DAC and P-DAC have been successfully synthesized and characterized. The ultraviolet-visible (UV-Vis) absorption of M-DAC and P-DAC showed in the range of 373 nm to 394 nm and exhibited maximum photoluminescence (PL) emissions at 466 and 481 nm in the film state. PL wavelength of P-DAC is red-shifted by 15 nm than that of M-DAC. This is because carbazole is substituted for para position and the conjugation length is increased. M-DAC and P-DAC OLED devices exhibited current efficiency of 3.09 and 2.80 cd/A and C.I.E(x,y) values of (0.17, 0.27) and (0.18,0.33). [ABSTRACT FROM AUTHOR]

HT

Nonlinear optical properties of 24 derivatives of [2.2]paracyclophane (pCp) have been analyzed. The set of the compounds studied include such classes as β-diketones, formyl-metoxy and formyl-hydroxy derivatives of pCp, pCp-Cr(CO)3, imines including Schiff bases. All molecules studied exhibit second harmonic generation ability, the efficiency of which was measured by the powder technique. In order to elucidate the role of intramolecular charge transfer due to transannular interaction in pCp the DFT calculations of the number of benzene analogues have been performed as well. For the first time the diastereomeric approach for the design of NLO materials was proposed and successfully utilized. [ABSTRACT FROM PUBLISHER]

The structural characterization of the orientation and elongation under shear flow in Lyotropic Chromonic Liquid Crystals (LCLCs) molecules, Sunset Yellow FCF (SSY), was performed by in situ rheological small/wide angle X-ray scattering (Rheo-SAXS/WAXS). The X-ray measurement results clearly demonstrated that the stacked aggregates were oriented and elongated to the shear direction under shear flow. Further shear rate increase caused the enhancement in the orientation and elongation with the inter-aggregate distance constant, and then the structural change decreased implying the onset of the orientation saturation at high shear rates. [ABSTRACT FROM AUTHOR]

The material (LC#11) we are reporting in this communication is a chiral fluorinated organosiloxane liquid crystal which has a long chain hydrocarbon head and ending with a straight trisiloxane terminus. Polarized optical microscopic studies revealed that the material exhibits SC, SAphases along with a co-existent biphasic region. The material responds to electric field; at low temperature the response is slow. Tilt angle measurements as a function of temperature are carried out using optical extinction method. Low frequency dielectric studies are carried out using Wayne Kerr precision impedance analyzer. [ABSTRACT FROM AUTHOR]

A report on the dielectric response of the liquid crystal compounds - heptyl oxy benzylidene butyl aniline and heptyl oxy benzylidene hexyl aniline – in various smectic and nematic phases under an applied biasing dc electric field is presented. It is found that the orientation of the molecule about the applied dc field is governed by the associated dipole, the structural arrangement of the molecules in different smectic or nematic phase and the ionic motion. Comparative study on pure and silver nanoparticles doped compounds reveal the presence of nanoparticles in the system affecting the local molecular arrangement supporting our earlier findings. [ABSTRACT FROM AUTHOR]

Solid phase catalyst-free Biginelli synthesis of novel 5-carbethoxy-4-(3-bromo-4-hydroxy-5-methoxyphenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-one (C15H17BrN2O5) and 5-carbethoxy-4-(3-bromo-4-hydroxy-5-methoxyphenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-thione (C15H17BrN2O4S) has been carried out under microwave irradiation at 400W. The structures of both compounds were confirmed by1H NMR,13C NMR, Mass, FT-IR, Elemental analysis, and single crystal X-ray diffraction method. The single crystals of both compounds were obtained by crystallization in 0.35 × 0.30 × 0.25 mm dimension for (C15H17BrN2O5) and 0.35 × 0.32 × 0.30 mm dimension for (C15H17BrN2O4S). Both compounds, (C15H17BrN2O5) and (C15H17BrN2O4S) crystallizes in the monoclinic P21/c space group and shows four and two intermolecular hydrogen bonds, respectively. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the dynamic proprieties of one-dimensional system of a classical Brownian particle immersed in a symmetric periodic Remoissenet-Peyrard potential using the Fokker Planck equation. This equation is solved by the Continued fraction expansion method (CFEM). Our results presented for different physical situations, indicated that the dynamical properties are very sensitive to the structure of the Remoissenet-Peyrard potential. Further, we have shown how translational and oscillator motion show up in the dynamic conductivity. Possible applications of this model lie in the field of solid electrolytes and molecular crystals. [ABSTRACT FROM AUTHOR]

The novel 4-(4,5-dimethoxy-2-nitrophenyl)-2,6-dimethyl-3,5-dicarbethoxy-1,4-dihydropyridine was synthesized through multicomponent one pot Hantzsch ester synthesis using 4,5-dimethoxy-2-nitrobenzaldehyde, ethyl 3-oxobutanoate, and ammonium carbonate under microwave irradiation and subsequently characterized by several spectroscopic techniques, i.e., ESI mass, IR,1H, and13C NMR along with single crystal X-ray diffraction method. The single crystal of 4-(4,5-dimethoxy-2-nitrophenyl)-2,6-dimethyl-3,5-dicarbethoxy-1,4-dihydropyridine (C21H26N2O8) was developed in 0.35 × 0.30 × 0.25 mm dimension in methanol. The crystal structure parades only intermolecular hydrogen bonding of the N(2)-H(2A) … O(2) type and the boat conformation of the dihydropyridine ring. [ABSTRACT FROM PUBLISHER]

The effect of polarization on the energy exchange of charge states in molecular media is studied for the case when no external electric field exists. Measurements of the light yield of organic molecular crystals excited by ionizing radiations are used to verify theoretical hypotheses. This allows us to carry out experiments for a wide range of the initial density of charge states. The polarization process initiates the primary recombination of hot carriers those are generated in the particle track. This reduces the radioluminescence (RL) energy yield of organic molecular crystals with increasing the specific energy loss of an ionizing particle. [ABSTRACT FROM AUTHOR]

The reaction of Cu(AC)2·H2O with 4-diethylamino-2-hydrogen-benzaldehyde (Hdahb) in methanol and water under solvothermal conditions leads to the formation of a novel dinuclear complex [Cu2(dahb)4] (1) (C44H56Cu2N4O8,Mr = 896.03,Dcalcd= 1.404 g cm−3). The compound belongs to the monoclinic system space groupP21/c, and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It consists of dinuclear unit, which is bridged byμ2-phenolato oxygen. The {Cu2IIO2} core displays dominant antiferromagnetic interactions from the nature of the binding modes throughμ2-O. [Supplemental materials are available for this article. Go to the publisher's online edition of Molecular Crystals and Liquid Crystals to view the free supplemental file.] [ABSTRACT FROM AUTHOR]

This paper investigates the changes in the optical and discharge characteristics during the panel-aging process in ac plasma display panel as a parameter of the operating frequency. The resulting changes in the optical and discharge characteristics, including the firing voltage, dynamic voltage margin, three-dimensional IR emission, and SEM image, are then compared for the three different operating frequencies (10, 25, and 50 kHz) during the panel-aging process. Our experimental results confirm that the 50 kHz operating frequency is very effective in obtaining the uniform surface morphology of the MgO thin film during the panel-aging process. [ABSTRACT FROM AUTHOR]

In this paper, the voltage level of the negative falling ramp in the reset waveform is lower, the accumulated wall charges during the ramp-up period are more erased between A-Y electrodes, thus, reducing the number of wall charges prior to address discharge. In particular, the measured Vtclosed-curves and the weak and strong discharge characteristics corresponding IR emission profiles show that fewer wall charges prior to an address discharge induce a decrease in the statistical time lag during the address period. The discharge transient contours of simultaneous discharges are changed by the wall voltage states after reset discharge, thereby influencing the statistical discharge time lag of the address discharge for the stable drive, thereby resulting in stable and fast addressing. [ABSTRACT FROM AUTHOR]

PDP often generates worm-like patterns on a displayed image because it employs an error diffusion method to maintain the quality of the input image by using limited number of gray-levels, which is quite essential for reducing dynamic false contours of PDP. To reduce worm-like patterns of PDP, an adaptive three-dimensional error diffusion method based on interrelation of neighboring frames is proposed. The interrelation of frames is estimated from the difference of adjacent frames, and the amount of quantization error for the spatial and temporal direction is adaptively changed depending on the magnitude of the frame difference. [ABSTRACT FROM AUTHOR]

The stacked CuGa/In metallic precursor thin films were fabricated and annealed at low temperature of 200°C before the selenization for fabricating Cu(In,Ga)Se2photovoltaic absorber. The pre-annealing of Cu-In-Ga precursor was found to reduce Cu9Ga4phase and increase the formation of Cu16(In,Ga)9phase, which may be preferable for the subsequent selenization in terms of homogenizing Ga across the absorber thickness. However, the replacement of In with Ga in the ternary phase produced large amount of free-In, which gave rise to blistered area as shunt paths after the selenization. The performance of solar cell fabricated using the pre-annealed precursor was heavily deteriorated compared to the not-annealed precursor. [ABSTRACT FROM AUTHOR]

The vibration in AC-PDPs was investigated to understand the relationship between electric and mechanical oscillations. The vibration peaks from AC-PDPs were observed at 4900, 9750, 14650, and 19550 Hz. These peaks were corresponded to the frequency components of applied power. The vibration intensity at different peaks was linearly increased with rising applied voltage regardless of discharge, and this implied the effects of discharge on vibrations were very small. From these results, the origin of vibrations in AC-PDPs was mainly the electric field due to displacement current. [ABSTRACT FROM AUTHOR]

The edge sealing process of vacuum glazing panel manufacture is one that requires high reliability in order to maintain a vacuum state between two sheets of glass. In this study, a method of melting and sealing two sheets of glass using the hydrogen mixed gas torch during edge sealing was conducted. During melting and sealing, the deflection effect of the edge part is affected by process parameters such as flow rate of hydrogen mixed gas, moving speed of torch, and distance between the torch and the glass, among others. In order to analyze the correlative relationship of the shape prediction and the sealing shape of the edge part according to the process parameters, data was obtained by conducting sealing experiments and setting shape parameters for the lower melting part. A mathematical experiment equation that can predict the shape of the lower edge part according to the process parameters was developed by conducting nonlinear multiple regression analysis based on the data obtained for the shape parameters. In addition, sensitivity analysis according to the changes in the process parameters was carried out and the effects of the process parameters on the edge shape parameters were analyzed by using the developed mathematical equation. [ABSTRACT FROM AUTHOR]

We report a new efficient exciton blocking material, tris(2,4,6-trimethyl-3-(pyridin-3-l)phenyl) (3TPYMB), for organic solar cell applications. The introduction of 3TPYMB as an exciton blocking layer instead of well known BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) results in the significant improvement of short circuit current (Jsc) and open circuit voltage (Voc) in the boron subphthalocyanine (SubPC)/C60based organic solar cell devices. As the results, the power conversion efficiency is enhanced by 11.8%. Such improvement with this new exciton blocking layer is mainly attributed to the good electron transportation by deep penetration of Al cathode metal to 3TPYMB layer. [ABSTRACT FROM AUTHOR]

Cu(In,Ga)Se2(CIGS) films were deposited by the three-stage co-evaporation process and the effect of the second stage substrate temperature on device performance were evaluated. With increasing the substrate temperature, the preferred orientation of CIGS was found to be changed from (112) to (220), however, the Ga double grading became weaker and nearly flat for the (220) textured CIGS grown at 570°C. Despite of (220) preferred orientation, the conversion efficiency decreased mainly due to the poor fill factor and open circuit voltage. It is suggested that increasing the growth temperature in order to get (220) preferred CIGS may destroy the advantage of double-graded Ga profile. [ABSTRACT FROM AUTHOR]

Solar cell modules mainly consist of EVA film and a metal grid. The EVA film is used as waterproof and UV-resistant, which makes it an ideal adhesive film for solar modules installed outdoors. As well, standard crystalline solar cells are generally fabricated with the front grid pattern of silver paste contact. Metal grid cannot help accompanying with shading losses caused by the presence of metal on the top surface of the solar cell, which prevent light from entering the solar cell. The shading losses are determined by the transparency of the top surface, which, for a planar top surface, is defined as the fraction of the top surface covered by metal. In order to fabricate highly efficient solar cell devices, the shading losses should be minimized. In this article, a theoretical estimation has been made to construct a morphologically modified configuration of EVA film so as to minimize the shading losses. According to our numerical calculations and optical simulations, by adopting only slightly modifying the EVA film, the transparency of solar cell modules can be significantly increased by as much as 4%. [ABSTRACT FROM AUTHOR]

The deposition rate of polysilicon and the temperature and concentration profiles of the reactant gases in a monosilane Siemens reactor were compared for rod diameters of 10–120 mm using the computational fluid dynamics method. It was found that the power consumption primarily depends on the Si rod diameter and the Si deposition rate. The relationship between the power consumption and the Si deposition rate at different Si rod diameters was established from the accumulated experimental data of a pilot-scale four-rod reactor, and it is incorporated into the MonoSim-S software package. [ABSTRACT FROM AUTHOR]

In 2004, therefore, the name of the symposium was changed from LCMD to ADMD to include these advanced display devices, and the publication of the proceedings of ADMD was started as a special issue of Molecular Crystals and Liquid Crystals. Nine plenary lectures, 24 invited lectures, and 95 poster papers were presented and there were more than 200 participants. The 23rd International Symposium on Advanced Display Materials and Devices (ADMD 2019) organized by South China University of Technology and held at Dongfang Hotel, Guangzhou, China, on 23-25 July, 2019. [Extracted from the article]

We report calculated2H nuclear quadrupole coupling constants and asymmetry parameter in deuterated crystalline oxalic acid dihydrated polymorphs within a full-potential linear combination of Gaussian-type orbitals employing both Density Functional Theory and Hartree-Fock approximation. The Becke's hybrid exchange B3 and the Lee, Yang and Parr correlation functionals were employed. Their dependence with basis set, interelectronic correlation, structural changes and crystal field environment are reported. [ABSTRACT FROM PUBLISHER]

A novel three-component one-pot synthesis of 4-(4,5-dimethoxy-2-nitrophenyl)-2,6-dimethyl-3,5-dicarbmethoxy-1,4-dihydropyridine from methyl 3-oxobutanoate, ammonium carbonate, and 4,5-dimethoxy-2-nitrobenzaldehyde has been carried out by typical Hantzsch synthesis. The single crystal was obtained by crystallization from methanol in 0.30 × 0.20 × 0.20 mm dimensional of 4-(4,5-dimethoxy-2-nitrophenyl)-2,6-dimethyl-3,5-dicarbmethoxy-1,4-dihydropyridine (C19H22N2O8), which was investigated by X-ray diffraction. The compound crystallizes in the monoclinic P21/c space group with unit cell dimensions a = 14.4830(3) Å, b = 8.66000(10) Å, c = 15.1036(3) Å, α = 90°, β = 90.0870(10)°, γ = 90°.1H NMR (hydrogen-1 nuclear magnetic resonance), mass, and IR (infrared) spectroscopic methods of the compound are also described. [ABSTRACT FROM PUBLISHER]

One fluorinated terphenyl compound was studied by polarizing microscopy, x-ray diffraction and dielectric spectroscopy. It exhibits the nematic phase over a range of 107.80. The average intermolecular distance was observed to be more than in systems without any lateral fluorine substitution. Apparent molecular length was found to be more than the molecular model length, suggesting presence of antiparallel molecular associations. Optimized geometry, obtained by molecular modeling, yielded a dipole moment of 6.68 D. The observed principal dielectric constants are consistent with respective components of dipole moments and show quite a high value of dielectric anisotropy. The threshold voltage and the splay elastic constant have also been determined. Flip-flop mode dielectric relaxation frequency is found to increase with temperature, and the activation energy for the process is found to be 35.53 kJ mol–1. [ABSTRACT FROM AUTHOR]

Asymmetry of pair potential plays a crucial role in the formation of mesophases in molecular systems. Variation of such asymmetry is closely related to the constituents of the molecules as well as their positions. To investigate the asymmetry as well as its effect on molecular behavior, a few polar biphenyl and non-polar 2,5 disubstituted pyridine derivatives have been chosen. The intermolecular interaction energy between a pair of molecules has been calculated with the help of a standard method as prescribed by Claverie (Claverie, P. (1978). Elaborations of approximate formulas for interactions between large molecules: Applications in organic chemistry. In: B. Pullman (Eds.), Inter Molecular Interactions from Diatomic to Biopolymers, J. Wiley & Sons Ltd.: Hoboken, NJ, 217–226.). Molecular geometry of all the selected systems was fully optimized without any constraint, and the net atomic charge and the dipole moment on each atomic center was calculated using the Gaussian03 program with density functional B3LYP method using 6-31G** as the basis set. The dispersion and the short range repulsion energy terms have been calculated using semiempirical Kitaigorodskii's “6-exp” formula. An attempt has been made to explain the phase sequences on the basis of the ratios of various interaction energy terms. Supplemental materials are available for this article. Go to the publisher's online edition of Molecular Crystals and Liquid Crystals to view the free supplemental file. [ABSTRACT FROM AUTHOR]

The field-induced molecular reorientation of liquid crystals is usually described by the Frank-Oseen equation with several simplifying assumptions. Among them the 'classical' theory ignores thermal fluctuations in the liquid crystal structure. As a consequence, the static Frank-Oseen equation may give inconsistent results in some details of the reorientation process. This work is aimed to include formally the orientational fluctuations in the field-induced reorientation process in nematics. The simplified approach presented here is a 'zero-order' approximation of the problem, nevertheless even in this form it allows for correct physical interpretation of the process for fields up to the threshold. [ABSTRACT FROM AUTHOR]

We consider a nonlinear system formed by a thin nematic slab immersed in vacuum, submitted to the action of a high-intensity normally-incident plane electromagnetic wave. We solve simultaneously, by using a numerical scheme, the director's orientational configuration and Maxwell's equations for this system using homeotropic soft boundary conditions. For a given field intensity, we find multiple equilibrium director's configurations. In addition, we study the reflectance versus the wavelength and the field intensity. [ABSTRACT FROM AUTHOR]

Two key parameters for the performance of an organic photovoltaic cell are the exciton diffusion length and the charge carrier mobility. Considering these parameters, columnar liquid crystals, with strong pi-orbital overlap between neighbouring cores, are promising materials. We describe our strategy towards the synthesis of both donor- and acceptor-type materials exhibiting a hexagonal columnar mesophase at the operating temperature range of the cell, including room temperature. We present the alignment behaviour of these materials when submitted to a thermal annealing, and, in particular, an approach to obtain thin open films with homeotropic orientation. [ABSTRACT FROM AUTHOR]

In this paper, we employ an express and high-throughput method fabricating micro- and nano-grooves for liquid crystal (LC) molecules alignment. Splitting the polymer film triggers the crack front vibrating back and forth between the two substrates. The propagating wave front brings out self-assembled polymer grooves extending over a large area. The period of the crack induced self-assembled grooves is tunable which consists with the theoretical prediction. This crack-induced grooving (CIG) method can avoid the drawbacks caused by traditional rubbing and provide anchoring energy comparable to that using polyimide rubbing. This novel CIG method offers an appealing alternative to existing technologies for LCs alignment. [ABSTRACT FROM AUTHOR]

We discuss the prerequisites for the formation of the structure with a period of six layers in antiferroelectric liquid crystals. We find that such a structure can appear in the region where the incommensurate helical pitch in the [image omitted] phase approaches six layers, if biquadratic coupling favoring uniplanar tilts in neighboring layers is already significant and if electrostatic dipolar interactions favor parallel ordering of dipoles in neighboring layers. [ABSTRACT FROM AUTHOR]