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[Display omitted] • Crystal structure analysis reveals an orthorhombic crystal system for 1-(carboxymethyl)cyclohexyl methanaminium dihydrogenphosphate. • The presence of phosphate units enhances stability due to structural robustness, while organic components introduce flexibility and specific reactivities. • Integration of inorganic units into conjugated structures impacts electron behavior, offering potential applications in optical nonlinearity. • Hirshfeld surface analysis reveals specific interaction types within the molecules, highlighting H•••H (53.8%), O•••H (42.9%), and O•••O (2.2%) contributions. • Void volume calculations reveal a lack of substantial cavities in the crystal, with electron density exhibiting openness in regions of interspecies approaches. The investigation into the crystal structure of 1-(carboxymethyl)cyclohexyl methanaminium dihydrogenphosphate endeavors to unravel the intricate molecular interactions at play. Utilizing Hirshfeld surface analysis, we delineate the specific types of interactions within the molecules. Fingerprint plots and molecular surface contours (dnorm, di, and de) vividly illustrate the proportional contributions of H...H (53.8%), O...H (42.9%), and O...O (2.2%). Further characterization through FTIR and UV–Vis spectroscopy enhances our comprehension. In contrast, the molecular arrangement's reinforcement stems from the N H... O interaction, leading to a linear chain. Through FTIR and FT-Raman experiments, we discern functional groups, contrasting experimental results with theoretical values. Mulliken atomic charges are meticulously examined, indicating reduced reactivity and heightened stability across diverse environments. Exploration of energy gaps in HOMO-LUMO and Density of States (DOS) spectra reveals coherence, supported by Natural Bond Orbital (NBO) Analysis, accentuating the equilibrium in energy during donor and acceptor transitions. This holistic approach enriches our understanding of the structural intricacies and stability factors inherent in the examined compound. [ABSTRACT FROM AUTHOR]

The lead-free dielectric compound Bi(Mg 2/3 Ta 1/3)O 3 (BMT) has been synthesized at high temperature by a low-cost solid-state method. The X-ray diffraction (XRD) technique reveals that the fabricated sample has an orthorhombic crystal system. The scanning electron microscope (SEM) image displays the uniform distribution of grains on the surface of the specimen. The dielectric parameters (permittivity (ε r), and loss tangent (tan δ) are studied over a wide range of temperature (150–500 °C) and frequency (1 kHz–1 MHz). The temperature dependent conductivity plot follows Universal Johnson's power law. The complex impedance and modulus spectrum illustrate the electrical behavior of the compound at various frequency and temperature. The Nyquist spectra show the presence of the effect of grain and grain boundary in the synthesized compound. The grain resistance value declines with the rise in temperature that shows the presence of a negative temperature coefficient (NTCR) behavior in the compound. The complex modulus spectra display the occurrence of the conduction mechanism in the specimen. The reported compound has a relative dielectric constant and loss of 22 × 103 and 1.8 respectively at 1 kHz frequency and 500 °C, thus becoming an efficient applicant for dielectric applications that can operate at higher temperatures. [ABSTRACT FROM AUTHOR]

The laminated nature of shale rocks leads to different mechanical properties parallel and perpendicular to the bedding plane, which is known as transverse isotropy (TI). If natural fractures (NFs) are present, the additional elastic anisotropy is introduced within the bedding plane, making shale an orthorhombic (OB) medium. Most current geophysical log interpretations ignore such shale anisotropies, resulting in erroneous estimates of the elastic moduli, brittleness, and stress gradient, which consequently causes problematic or suboptimal drilling, completion, and hydraulic-fracturing design. The objective of the current study is to investigate the effects of the two shale anisotropies on geomechanical-property characterizations, and, hence, on operational designs. In this paper, synthetic OB-rock stiffness tensors are built by introducing NF sets in a vertical symmetric-axis (VTI) background. Then, the VTI model, which ignores the NF effect, and the isotropic model, which ignores both anisotropies, are applied to the synthetic OB rock to interpret the stiffness coefficients, elastic moduli, and stresses. The results are compared with the "true" values interpreted from the original OB-rock stiffness tensors. The impacts of the two types of shale anisotropies on shale-rock geomechanical-property characterizations-and, hence, operational designs-are examined. According to the modeling results, the lamination-induced anisotropy is more significant than the NF-induced anisotropy when predicting Young's modulus. Besides, ignoring the two anisotropies can lead to an overestimation of both the minimum-horizontal-stress magnitude and the stress contrast; the overestimation is larger for stiffer zones and less-tectonically-active zones. As a result, ignoring two anisotropies can lead to an overoptimistic design of the mud-weight window, resulting in higher risks of borehole tensile failure and shear failure. Ignoring the two anisotropies will not alter the brittleness-index (BI) trend observed in the OB rock. However, the stress contrast is overestimated, which will lead to shorter stage-spacing design and suboptimal selections of perforation locations. If one is ignoring the anisotropy induced by NFs, the fracture width is underestimated, leading to insufficient proppant size or pumping-amount design and, hence, to suboptimal low fracture conductivity. [ABSTRACT FROM AUTHOR]

The crystal structure of betekhtinite from Dzhezkazgan copper ore deposit, Kazakhstan, has been refined to R 1 = 0.047 for 1321 unique observed reflections. The mineral is orthorhombic, Immm, a = 3.9047(6), b = 14.796(2), c = 22.731(3) Å, and V = 1313.3(3) Å 3 . Structure refinement revealed five additional partially occupied Cu sites compared to the previous structural study. The structure contains one Pb and thirteen Cu sites. The coordination of the Pb site is sevenfold. Coordination geometries of the Cu sites are variable: The Cu1, Cu2, Cu3 Cu6, Cu7, Cu8, and Cu9 sites are tetrahedrally coordinated, whereas Cu4, Cu5, Cu10, Cu11, and Cu13 have a triangular coordination. The Cu12 site is coordinated by two S atoms to form a CuS 2 dumbell. The crystal structure of betekhtinite is based upon complex Pb-Cu sulfide rods running parallel to the a axis. The rods have a rhombus-like cross sections with lateral dimensions of ca. 11 x 16 Å 2 . The core of the rod is composed from the CuS 4 tetrahedra and may be considered a module extracted from the archetype structure of fluorite, CaF 2 . The tetrahedral columns are further incrustated by the Cu4S 3 and Cu5S 3 triangles and Pb atoms to form the [Pb 2 Cu 1 6S 15 ] rods, which are linked to each other along the b axis via S6 atoms. The low-occupied Cu sites are located in between the rods. The structural formula determined on the basis of the crystal-structure refinement can be written as Pb 2 Cu 22.18 Fe 1.04 S 15 , which is in good agreement with the chemical analyses of betekhtinite and disagrees notably with the formula Pb 2 (Cu,Fe) 21 S 15 suggested by Dornberger-Schiff and Höhne. The general crystal chemical formula of betekhtinite can be written as Pb 2 (Cu,Fe) 22-24 S 15 . Information-based structural complexity parameters for betekhtinite are: I g = 3.696 bits/atom and I G,total = 144.131 bits/cell. Decomposition of betekhtinite into a mixture of galena (PbS; I g = 1.000 bits/atom; I G,total = 2.000 bits/cell) and chalcocite (Cu 2 S; I G = 1.500 bits/atom; I G,total = 12.000 bits/cell) at temperatures above 150 °C is associated with the loss of structural complexity and the rise of configurational entropy of the system. [ABSTRACT FROM AUTHOR]

Ternary p-type copper–tin–sulfide photoelectrodes are prepared on various substrates by using the sulfurization of co-sputtered Cu–Sn metal precursors. The influence of the [Cu]/[Cu+Sn] molar ratios in samples on structural and photoelectrochemical performances of samples in various electrolytes is examined. X-ray diffraction patterns of samples after the sulfurization process show that the samples change from the cubic Cu 2 SnS 3 phase, the cubic Cu 2 SnS 3 /orthorhombic Cu 4 SnS 4 mixing phases to the orthorhombic Cu 4 SnS 4 phase with an increase in the [Cu]/[Cu+Sn] molar ratio in metal precursors. The phase transition from the cubic Cu 2 SnS 3 to the orthorhombic Cu 4 SnS 4 phase is observed at the [Cu]/[Cu+Sn] molar ratio in the range of 0.72–0.73 in metal alloys. Direct energy band gaps of the samples are in the range of 0.96–1.22 eV. All samples are the p-type semiconductors with the carrier concentration and mobility in the ranges of 8.79 × 10 18 –3.57 × 10 20 cm −3 and 2.22–0.27 cm 2 /V s, respectively, depending on the [Cu]/[Cu+Sn] molar ratio in samples. The maximum photoelectrochemical performances of the samples in 0.5 M K 2 SO 4 and 1 M NaCl aqueous solutions are 0.55 and 0.34 mA/cm 2 at an external potential of −1.2 V versus an Ag/AgCl reference electrode under light illumination with the light intensity of 100 mW/cm 2 , respectively. [ABSTRACT FROM AUTHOR]

An orthorhombic velocity model covers anisotropy and vertical/horizontal heterogeneity in the uniform 3D framework. It is important to define the azimuthal dependence of kinematic parameters of this model in the phase and group domains. I have derived equations for azimuthal dependent anellipticity in orthorhombic media and a simple equation to link the group and phase azimuths at zero horizontal slowness projection (zero offset). I found that the orthorhombic media cannot be treated as azimuthally dependent transversely isotropic media. To define the effective kinematic properties from a multilayered orthorhombic medium is a nontrivial task, and I have developed an approximate least-squares solution for that problem. Numerical examples with the orthorhombic model and its special cases (a transversely isotropic model with vertical and horizontal symmetry axes and an elliptical isotropic model) were used to illustrate the effect of the individual orientation of symmetry planes on the effective kinematic properties. [ABSTRACT FROM AUTHOR]

Anelliptic approximations for phase and group velocities of qP waves in transversely isotropic (TI) media have been widely applied in various seismic data processing and imaging tasks. We have revisited previously proposed approximations and suggested two improvements. The first improvement involves finding an empirical connection between anelliptic parameters along different fitting axes based on laboratory measurements of anisotropy of rock samples of different types. The relationship between anelliptic parameters observed was strongly linear suggesting a novel set of anisotropic parameters suitable for the study of qP-wave signatures. The second improvement involves suggesting a new functional form for the anelliptic parameter term to achieve better fitting along the horizontal axis. These modifications led to improved three-parameter and four-parameter approximations for phase and group velocities of qP-waves in TI media. In several model comparisons, the new three-parameter approximations appeared to be more accurate than previous approximations with the same number of parameters. These modifications also served as a foundation for an extension to orthorhombic media, where qP velocities involved nine independent elastic parameters. As determined by previous researchers, qP-wave propagation in orthorhombic media could be adequately approximated using just six combinations of those nine parameters. We have developed novel six-parameter approximations for phase and group velocities for qP-waves in orthorhombic media. The orthorhombic phase-velocity approximation provides a more accurate alternative to previously known approximations and can find applications in full-wave modeling, imaging, and inversion. The group-velocity approximation is also highly accurate and can find applications in ray tracing and velocity analysis. [ABSTRACT FROM AUTHOR]

The reversible electrochemical insertion/extraction of Mg2+ and Li+ into/from a crystalline has been found in orthorhombic Mo9Se11 (o-Mo9Se11), the crystal structure of which is composed of molybdenum cluster units. The insertion/extraction reversibility of bivalent ion, Mg2+, could be ascribed to improvement of slow diffusion in the host lattice through the delocalization effect of electrons induced by cluster structure as supposed in Chevrel phase. The characteristic of Li/Mg-ion half-cell with o-Mo9Se11 cathode, such as discharge curve and theoretical capacity, are discussed based on the electronic structure. A part of discharge curve in the insertion process of Li+ was likely ascribed to the psuedogap structure in the density of state for the electronic band. The reversible capacity of o-MgxMo9Se11 was below 40% of the theoretical capacity deduced from the molecular orbital model, whereas over 80% of that was observed in o-LixMo9Se11. The smaller reversible capacity for Mg2+ could be ascribed to the Coulomb repulsion between bivalent Mg-ions confined in the one-dimensional channel of o-Mo9Se11, which highly prevents ion-insertion for bivalent Mg-ions compared with that for monovalent Li-ions. We suggest that both delocalized electronic structure and high dimensional ion-channel are necessary to realize reversible cathodes of Mg-ion battery with high capacity. [ABSTRACT FROM AUTHOR]