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Schiff base (HL) N1,N3-bis(4-(methylthio)benzylidene)-5-nitrobenzene-1,3-dihydrazide (HL) has been prepared from condensation of 4-(methyl thio)benzaldehyde with 5-nitrobenzene-1,3-dihydrazide. Binucleated mixed ligand complexes of nickel(II) ([Ni2(L)(dmphen)2]Cl2, [Ni2(L)(phen)2]Cl2) and cobalt(II) ([Co2(HL)(dmphen)2]Cl2, [Co2(HL)(phen)2]Cl2) complexes have been synthesized from Schiff base (HL) and 1,10-phenanthroline/2,9-dimethyl-1,10-phenanthroline. The synthesized compounds have been characterized by elemental analysis, 1H-NMR, 13C-NMR, FT-IR, UV-Visible, magnetic moment, SEM, powder X-ray diffraction and molar conductivity measurements. Further, the Schiff base and its metal complexes have been investigated for fluorescence activity and molecular docking studies. In addition, Schiff base and its metal complexes were screened for antimicrobial activity against bacteria: Escherichia coli, Bacillus subtilis and fungi: Sclerotium rolfsii and Macrophomina phaseolina. KEY WORDS: Growth inhibitors, Ternary complex, Tuberculosis, Fluorescence activity, Crystal system Bull. Chem. Soc. Ethiop. 2021, 35(3), 499-511. DOI: https://dx.doi.org/10.4314/bcse.v35i3.3

Highly transparent nonlinear Thiourea cadmium hydrogen borate (TCHB) single crystal grown by slow evaporation method is investigated for optoelectronic applications. Single crystal XRD provides details about the lattice structure. FTIR vibrational spectroscopic study identifies the functionals that make up the crystal system. Elemental composition is determined from the EDAX spectrum. UV spectral analysis is performed to determine the transparency range, absorption edge limit, and band gap value at which the crystal can be run. The linear behavior of TCHB is analysed by studying the optical constants from the transmittance values. TG/DTA analysis is done to find out the thermal stability. Vickers microhardness test classifies TCHB as a soft material and elasticity, brittleness and other mechanical properties are assessed from the hardness value. Second harmonic optical study affirms frequency doubling of Nd:YAG laser. Third order measurements, such as, nonlinear absorption co-efficient (β), nonlinear refraction (n2) and third order susceptibility (χ3) are calculated by the Z scan technique.

Despite dihalogenation of terminals is an effective strategy to achieve efficient nonfullerene acceptors (NFAs)-based organic solar cells (OSCs), hetero-dihalogenated terminals are quite difficult to obtain. Here, we firstly synthesized two new hetero-dihalogenated terminals (FCl-IC and FBr-IC) with a pair of fluorine/chlorine or fluorine/bromine at one terminal and three NFAs (Y-BO-FCl, Y-BO-FBr, and Y-BO-ClBr) with three hetero-dihalogenated terminals (FCl-IC, FBr-IC, and ClBr-IC) in a general process for OSCs, respectively. Y-BO-FCl neat film presents slightly lower energy level in comparison with those of Y-BO-FBr and Y-BO-ClBr. We, for the first time, obtained the single crystals of hetero-dihalogenated NFAs. From Y-BO-ClBr single crystal to fluorinated acceptor single crystals, the crystal systems and the intermolecular packing motifs have been significantly improved. The crystallographic and theoretical analysis indicate that Y-BO-FCl exhibits the most planar molecular geometry, the smallest intermolecular packing distance and the largest π−π electronic coupling among these acceptors. Moreover, PM6:Y-BO-FCl blend films present more order face-on orientation crystallinity, more suitable fiber-like phase separation, higher and more balanced charge mobility, weaker charge recombination in comparison with those of PM6:Y-BO-FBr and PM6:Y-BO-ClBr. As a result, up to remarkable PCE of 17.52% with enhanced FF of ca. 78% was achieved in binary Y-BO-FCl:PM6 devices compared to that of PM6:Y-BO-FBr (16.47%) and PM6:Y-BO-ClBr (13.61%), which is the highest efficiency for the hetero-halogenated NFAs-based OSCs. Our investigations demonstrate that fluorine/chlorine hetero-dihalogenated terminal is a new and effective synergistic strategy to induce significant difference in single crystallography and achieve high-performance hetero-halogenated NFAs-based OSCs.

Good quality single crystal of p-fluorobenzyl ammonium dihydrogen phosphate [PFBADP], a compound has been successfully grown from aqueous solution by slow evaporation solution growth method. The crystal system and lattice parameters are confirmed by the single crystal X-Ray diffraction analysis. An optical absorption study on the sample shows that the material is well suitable for optical applications. The functional groups of the compound are confirmed qualitatively by FT-IR spectral analysis. The photoluminescence studies indicate that the grown crystals have a green fluorescence emission. Dielectric studies have been carried out for the grown crystal and the results were discussed in detail.

Using a suitable gauge transformation matrix, we present a N -fold Darboux transformation for a Vakhnenko lattice system. This transformation preserves the form of Lax pair of the Vakhnenko lattice system. Applying the obtained Darboux transformation, we arrive at an exact solution of the Vakhnenko lattice system.

A method is introduced to determine lattice parameters using machine learning. Analysis is presented of the impact of experimental conditions on machine learning prediction, and possibilities for automated unit-cell solution are explored., A key step in the analysis of powder X-ray diffraction (PXRD) data is the accurate determination of unit-cell lattice parameters. This step often requires significant human intervention and is a bottleneck that hinders efforts towards automated analysis. This work develops a series of one-dimensional convolutional neural networks (1D-CNNs) trained to provide lattice parameter estimates for each crystal system. A mean absolute percentage error of approximately 10% is achieved for each crystal system, which corresponds to a 100- to 1000-fold reduction in lattice parameter search space volume. The models learn from nearly one million crystal structures contained within the Inorganic Crystal Structure Database and the Cambridge Structural Database and, due to the nature of these two complimentary databases, the models generalize well across chemistries. A key component of this work is a systematic analysis of the effect of different realistic experimental non-idealities on model performance. It is found that the addition of impurity phases, baseline noise and peak broadening present the greatest challenges to learning, while zero-offset error and random intensity modulations have little effect. However, appropriate data modification schemes can be used to bolster model performance and yield reasonable predictions, even for data which simulate realistic experimental non-idealities. In order to obtain accurate results, a new approach is introduced which uses the initial machine learning estimates with existing iterative whole-pattern refinement schemes to tackle automated unit-cell solution.

This Letter describes strong coupling of densely packed molecular emitters in metal-organic frameworks (MOFs) and plasmonic nanoparticle (NP) lattices. Porphyrin-derived ligands with small transition dipole moments in an ordered MOF film were grown on Ag NP arrays. Angle-resolved optical measurements of the MOF-NP lattice system showed the formation of a polariton that is lower in energy and does not cross the uncoupled MOF Q1 band. Modeling predicted the upper polariton energy and a calculated Rabi splitting of 110 meV. The coupling strength was systematically controlled by detuning the plasmon energy by changing the refractive index of the solvents infiltrating the MOF pores. Through transient absorption spectroscopy, we found that the lower polariton decays quickly at shorter time scales (

For the first time, double gadolinium tellurites of the composition GdMIITeO4.5 (MII — Sr, Ba) were synthesized by the solid-phase method. The solid-phase synthesis of samples was carried out from decrepitated gadolinium (III) and tellurium (IV) oxides, strontium, and barium carbonates according to the standard ceramic technology. The synthesis was carried out in the temperature range of 800-1100 °C. The samples obtained were confirmed by X-ray phase analysis. X-ray phase analysis was carried out on an Empyrean instrument in the XRDML Pananalitical format. The intensity of the diffraction maxima was estimated on a 100-point scale. X-ray diffraction patterns indexing of the powder of gadolinium tellurites — alkaline earth metals studied were carried out by the homology method. The reliability and correctness of the results of indexing the X-ray diffraction patterns are confirmed by the good agreement between the experimental and calculated values of the interplanar distances (d) and the agreement between the values of the X-ray and pycnometric densities. It was found that compounds GdSrTeO4.5 and GdBaTeO4.5 crystallize in the monoclinic system and have the unit cell parameters, namely GdSrTeO4.5 — a = 12.7610, b = 10.4289, c = 8.6235 Å, V° = 1141.83 Å3, β = 95.77°, Z = 5, ρrent. = 3.22, ρpikn. = (3.10±0.09) g/cm3; GdBaTeO4.5 — a = 15.7272, b = 15.8351, c = 7.1393 Å, V° = 1769.72 Å3, β = 95.53°, Z = 8, ρrent = 3.71, ρpick = (3.61±0.10) g/cm3. Using the Landiya method, the standard heat capacities of the compounds were estimated from the calculated values of the standard entropies, and the temperature dependences of the heat capacities of the gadolinium tellurites synthesized were determined in the temperature range of 298–850 K.

The single crystals of diethyl-2-(3-oxoiso-1,3-dihydrobenzofuran-1-ylidene) malonate (D23DYM) were grown successfully and efficiently by the standard slow evaporation method. The lattice cell parameters by XRD analysis also confirmed that the crystal system is Triclinic with the space group of Pī. The FTIR spectrum portrays the presence of major and active functional groups in D23DYM. The thermal studies explained the two major weight losses between 107 and 153 °C and 153 and 800 °C for D23DYM have been observed. It is very clear that the hardness profile of D23DYM increases with increase in load which confirms reverse indentation size effect (RISE), and the work-hardening coefficient 'n' was observed as 2.936. The negative photoconductive nature as the predominant property and the dielectric constant and dielectric loss are perfectly and accurately measured and properly reported. The structural properties by theoretical manner confirm the elucidation as well as the confirmation for XRD data and the computational way of identifying the lattice bond length and bond angles using software. Diabetes mellitus is the commonly occurring disease associated with lifestyle and feeding behavior of D23DYM—organic crystals are tested by the use of molecular docking. The binding affinity values for the standard inhibitor A74DME and investigational compound D23DYM were − 8.1 kJ/mole and − 8.3 kJ/mole, respectively, and in future may get proceeded for in vivo animal analysis as well as anti-cancer work as the benzofuran is present in the crystal and is better diabetic- and cancer-opposing agent.

Potassium hydrogen phthalate picrate (KHPP) was harvested by solution growth method at room temperature. The KHPP crystal system was identified monoclinic with the cell parameters, a = 5.08 A, b = 14.33 A, and c = 9.62 A by the single-crystal XRD study. The PXRD study ensures the KHPP crystal as in good crystalline nature. The FTIR spectrum confirms the various modes of functional groups available in the prepared KHPP sample. The linear optical study in UV–Vis–NIR region reveals that the sample possesses optical window between 282 and 1100 nm wavelength with band-gap energy 4.83 eV. The thermogravimetric and differential thermal analysis shows that the grown crystal has thermally stable upto 199.90 °C. The hard nature of the KHPP crystal was identified by the Vickers hardness study. The nonlinear optical study shows that the SHG efficiency is 1.72 times grater than that of KDP. This result indicated the suitability of the sample for nonlinear optical (NLO) applications.

Crystal structure, physicochemical and intermolecular charge-transfer-enhanced third order nonlinear optical properties of a new metal-organic cocrystal $$\{[\hbox {NiCl}_2(\hbox {C}_4\hbox {H}_{11}\hbox {N}_2)_2(\hbox {OH}_2)_2](\hbox {Cl})_2 (\hbox {OH}_2)_2\hbox {n}\}$$ (PNi) is reported. An intermediate piperazinium chloride created during the pH optimization reacts with the metal centre (Ni), forming mono-substituted piperazine metal-organic cocrystal. The PNi adopts octahedral coordination geometry with triclinic ( $$P\overline{1}$$ ) crystal system at its single crystalline phase. The crystal packing stabilization via $$\hbox {O}-\hbox {H}\cdots \hbox {Cl}$$ , $$\hbox {C}-\hbox {H}\cdots \hbox {Cl}$$ and $$\hbox {O}-\hbox {H}\cdots \hbox {O}$$ noncovalent charge-transfer interactions is observed from single-crystal X-ray diffraction analysis. The PNi single crystal is thermally stable up to 87 $$^\circ$$ C. The $$\hbox {H}_2\hbox {O}$$ molecules tend to evaporate at lower temperatures bringing moderate, rather sufficient thermal stability for using the title material in lasing applications. Vickers microhardness study revealed that the title crystal belongs to the soft material category. Investigation on dielectric properties showed polar dielectric nature of the material with consistent electronic polarizability ( $$\alpha =1.11\times 10^{22}\ \hbox {cm}^3$$ ). The optical bandgap of 5.17 eV from UV-DRS spectroscopic analysis shows PNi belongs to the wide bandgap material category. The third order nonlinear optical absorption ( $$\beta$$ ), nonlinear refractive index ( $$n_2$$ ) and third order nonlinear optical susceptibility ( $$\chi ^{(3)}$$ ) of PNi cocrystal using 532 nm CW DPSS laser are measured to be $$(0.067\pm 0.001)\times 10^{-4}\ \hbox {cmW}^{-1}$$ , $$(0.211\pm 0.0057)\times 10^{-8}\ \hbox {cm}^2\hbox {W}^{-1}$$ and $$(0.511\pm 0.09)\times 10^{-6}$$ esu, respectively. Intermolecular charge-transfer interactions and electronic polarizability well influence nonlinear optical properties and are proved possible by calculating the intermolecular charge-transfer interactions at the B3LYP/6-31G(d,p) level of calculations. Further, the nonlinear absorption coefficient ( $$\beta$$ ) was found to vary with the laser intensities, explicitly indicating the presence of excited state absorption assisted sequential 2PA in PNi cocrystal. Low onset limiting threshold for nanosecond pulsed and continuous-wave laser irradiance ( $$(1.66\pm 0.02)\times 10^{12}\ \hbox {Wm}^{-2}$$ and $$(0.804\pm 0.02)\times 10^{03}$$ $$\hbox {Wcm}^{-2}$$ , respectively) promotes the title material as an efficient candidate for optical limiting application.

This study delves into the variation in the fundamental aspects of electrical quantities with the partial substitution of Tm impurities at Bi-site in the Bi2.1-xTmxSr2.0Ca1.1Cu2.0Oy (0.00 ≤ x ≤ 0.30) ceramic system with the derivatives of electrical resistivity examinations and theoretical approaches. It is found that all the electrical characteristic properties tend to improve with the trivalent Bi/Tm substitution level up to x = 0.07 beyond which they degrade considerably due to the increment of non-superconducting barrier regions, permanent disorders, inhomogeneity, porosity, grain misorientation distribution, internal and surface omnipresent defects, microscopic cracks, and coupling interaction problems throughout the grain boundaries in the Bi-2212 crystal system. Thus, the optimum dopant level of x = 0.07 results in the transition from the over-doped state to optimally doped state in the Bi-2212 crystal system as a consequence of augmented hybridization mechanism. Further, the characteristic two-stage transition temperatures, gap coefficient, Josephson coupled, and thermal energies for the isolated grains and inter-grains are explored. The findings show that the optimum Bi/Tm substitution leads not only to stabilize the superconductivity in the homogeneous superconducting clusters as a result of the increment in the formation of active Cooper pairs but also to decrease significantly the location of resistivity in long-range coherent state due to the increment of hole trap energy. Additionally, a strong link is established between the structural disorders-defects and onset/offset ( $$T_{c}^{{onset}}$$ / $$T_{c}^{{offset}}$$ ) transition temperatures using the electrical resistivity features for the first time. The empirical model based on the impurity scattering and lattice strain in the crystal lattices displays that it is possible to achieve the possible highest $$T_{c}^{{onset}}$$ and $$T_{c}^{{offset}}$$ values of about 86.558 K and 86.445 K, respectively. To sum up, the paper with strong methodology between electrical quantities and structural disorders-defects depending on Tm impurity may be a pioneering research to explain why the characteristic features improve with the optimum substitution and especially open up a novel and feasible area for the advanced engineering, heavy industrial technology, and large-scale applications of ceramic materials.

We prove the existence of a random exponential attractor for a non-autonomous Zakharov lattice system with multiplicative white noise. We first transfer the stochastic lattice system into an equiva...

The space-group frequency distributions for two types of proteins and their complexes are explored. Based on the incremental availability of data in the Protein Data Bank, an analytical assessment shows a preferential distribution of three space groups, i.e. P212121 > P1211 > C121, in soluble and membrane proteins as well as in their complexes. In membrane proteins, the order of the three space groups is P212121 > C121 > P1211. The distribution of these space groups also shows the same pattern whether a protein crystallizes with a monomer or an oligomer in the asymmetric unit. The results also indicate that the sizes of the two entities in the structures of soluble proteins crystallized as complexes do not influence the frequency distribution of space groups. In general, it can be concluded that the space-group frequency distribution is homogenous across different types of proteins and their complexes.

Preferable, third-order nonlinear optical (NLO) single crystal, 3-Nitroanilinium chloride (3NACL) was auspiciously synthesised by slow evaporation technique. The crystal system of the synthesised 3NACL crystal was triclinic with centrosymmetric space group $${\text{P}}\bar{1}$$ was identified by single-crystal XRD studies. All the functional groups present in the sample and its respective vibrations were analysed through FTIR analysis. UV–Vis transmittance spectrum revealed that the synthesised material showed 83% transmittance and its cut-off wavelength was 281 nm. The mechanical stability and thermal property of the grown 3NACL crystals were ascertained by Vickers microhardness analysis and TG/DTA analysis. The intermolecular interaction of the 3NACL was scrutinized by Hirshfeld surface analysis. Dielectric studies revealed that dielectric constant and dielectric loss were high at lower frequency region due to the space charge polarization. Inclusion-free 3NACL crystal was used to analyse the Laser damage threshold (LDT) studies and its calculated LDT value was 4.3 GW/cm2. The third-order NLO parameters (β = 7.5472 × 10–12 m/W, η2 = 5.6931 × 10–19 m2/W, χ3 = 2.9491 × 10–13 esu) of the 3NACL material were statutorily evaluated by Z-scan studies. Here, β and η2 were positive, due to the saturated absorption and self-focusing effect as observed in open and closed aperture z-scan curve. Above all these findings, 3NACL was a suitable material for NLO and optoelectronic applications.

This study focused on the manufacturing of different lattice structures from Ti-6Al-4V ELI alloy with the laser beam-powder bed fusion (LB-PBF) method, which is expected to have potential applications in aviation and especially the medical field. The mechanical properties of these structures were investigated experimentally and numerically. The porous lattice systems, manufactured according to the optimum laser process parameters, with the repetitive periodic structure were designed in five different topologies (BCC, BCCZ, FCC, FCCZ and DIAMOND) and three different porosities (60, 75, 90%). The mechanical properties and damage mechanisms of the lattice structures were obtained by static compression tests. BCC and DIAMOND systems showed similar characteristics in terms of stress-compression elongation compared to other lattice systems, with the rods having the same orientation. It was observed that XYZ modification of BCC lattice system was more effective than the modification of FCC system in terms of rigidity and strength. The damage mechanism and stiffness values suggested that the DIAMOND lattice system could be a model that can be used in porous implant designs owing to its homogeneous deformation behavior and mechanical properties similar to trabecular bone. Numerical models were created where numerical results and static experiments converge considerably well. The numerical and experimental results were quite similar, and the maximum difference was below 7.7%.

In this paper, the thermodynamic, structural properties and vibrational spectrum of thorium dioxide have been studied using the Density Functional Perturbation Theory (DFPT) and Density Functional Theory (DFT) in the framework of first principles calculations. Quantum espresso software, which is an open source computing code, has been used in order to compute the kohn-Sham equations to obtain the minimum total energy of crystal. The vibrational spectrum of the thorium dioxide was examined along various symmetrical directions, and the results showed the dynamical stability of the crystal system. The quasi-harmonic Debye-Einstein model as implemented in GIBBS2 Code was used to calculate the thermodynamic properties of thorium dioxide at high temperatures and pressures. The simulation results showed that the Debye temperature of thorium dioxide decreased with increasing temperature at a constant pressure and increased with increasing pressure at a constant temperature. Increasing the Debye temperature indicated an increase in the crystal stiffness and the average sound velocity. It was observed that the volumetric thermal expansion coefficient and gruneisen parameter decreased exponentially with increasing pressure at a constant temperature, while increased with increasing temperature at a constant pressure, indicating an increase in heat transfer in the crystal lattice

This paper is devoted to periodic travelling waves in a two-dimensional nonautonomous weakly damped lattice system with linear coupling between nearest particles and periodic nonlinear substrate potentials. Nonlinear functional analysis is employed to prove the existence and uniqueness of periodic travelling wave solutions. In the case of small forcing and damping, Lyapunov–Schmidt reduction is employed to study the bifurcation of periodic travelling wave solutions and the asymptotic expressions of the bifurcating solutions.

Surfactant crystals can stabilize liquid foams. The crystals are adsorbed at bubble surfaces, slowing down coarsening and coalescence. Excess crystals in the liquid channels between bubbles arrest drainage, leading to ultrastable foams. The melting of crystals upon raising the temperature allows thermoresponsive foams to be designed. In the case of oil foams, the stabilization by crystals received substantial renewed interest in the last 5 years due to their potential applications, particularly in the food industry. For aqueous foams, several reports exist on foams stabilized by crystals. However, these two kinds of liquid foams possess similarities in terms of stabilization mechanisms and the design of surfactant crystal systems. This field will certainly grow in the coming years, and it will contribute to the engineering of new soft materials not only for food but also for cosmetics, pharmaceuticals, and biomedical applications.

Lattice constants such as unit cell edge lengths and plane angles are important parameters of the periodic structures of crystal materials. Predicting crystal lattice constants has wide applications in crystal structure prediction and materials property prediction. Previous work has used machine learning models such as neural networks and support vector machines combined with composition features for lattice constant prediction and has achieved a maximum performance for cubic structures with an average $R^2$ of 0.82. Other models tailored for special materials family of a fixed form such as ABX3 perovskites can achieve much higher performance due to the homogeneity of the structures. However, these models trained with small datasets are usually not applicable to generic lattice parameter prediction of materials with diverse compositions. Herein, we report MLatticeABC, a random forest machine learning model with a new descriptor set for lattice unit cell edge length ($a,b,c$) prediction which achieves an R2 score of 0.979 for lattice parameter $a$ of cubic crystals and significant performance improvement for other crystal systems as well. Source code and trained models can be freely accessed at https://github.com/usccolumbia/MLatticeABC, 13 pages

Structure solution for pseudo-merohedric twins having roughly equal individual volume fractions are described in detail via worked examples of varying complexity., Twinning by pseudo-merohedry is a common phenomenon in small-mol­ecule crystallography. In cases where twin-component volume fractions are markedly different, structure solution is often no more difficult than for non-twinned structures of similar complexity. When twin-component volume fractions are similar, however, structure solution can be much more of a problem. This paper presents hints and tips for such cases by means of three worked examples. The first example presents the most common (and simplest) case of a two-component pseudo-ortho­rhom­bic twin. The second example describes structure solution of a reticular threefold pseudo-hexa­gonal twin that benefits from use of an unconventional space-group setting. The third example covers structure solution of a reticular fourfold pseudo-tetra­gonal twin. All three structures are ultimately shown to be monoclinic crystals that twin as a consequence of unit-cell metrics that mimic those of higher symmetry crystal systems.

A comparative analysis of the molecular and crystal structures is performed for 5-[(diphenylphosphoryl) methyl]-4-phenyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (1) in individual crystal (1a) and a crystal solvate with dimethylformamide (DMF) in the 1:1 ratio (1b). The crystals of both modifications have the identical geometries of the molecule of the key compound, and the crystals (despite their different crystal systems and unit cells parameters) are characterized by the formation of an identical one-dimensional supramolecular motif in them due to classical N–H...O hydrogen bonds and weaker noncovalent – C-H ... S interactions in crystal 1a and CH ... N in crystal 1b. A tetragonal packing of one-dimensional motifs oriented along the smallest unit cell parameter are observed in both cases. Solvate molecules are localized in zero-dimensional cavities in crystal 1b. Despite a denser molecular packing in crystal 1b, the solid-state phase transformation is observed for its polycrystalline sample, and the powder X-ray diffraction method shows that it partially transforms into form 1a with time. The latter form is characterized by a less dense molecular packing in the crystal.

In [3] the solutions of a sigmoidal neural field lattice system based on an Amari-Hopfield neural field lattice model, in which the Heaviside function is replaced by a simplifying sigmoidal function characterized by a small parameter e, were shown to converge to the solution of the Heaviside lattice system as e → 0 , through an inflated lattice system which contains both of them. It was incorrectly claimed in the proof of Theorem 4 in [3] that the derivatives converge strongly in L 1 ( [ 0 , T ] , R ) rather than weakly. The proof is corrected here using the Banach-Saks theorem.