405 Results Found

An analytical analysis of the problem of the longitudinal tension of two-layered tubes with walls made of tetragonal crystals was carried out together with numerical calculations of the effective Young’s moduli and Poisson’s ratios of the...

For tetragonal lead tungstate (PWO) and other tetragonal crystals, we study modifications of the Bertin surfaces induced by either the distortion of crystallographic cells, the applied plane stress, or cell misalignment with respect to the specimen f...

Lead free piezoelectric crystals of (K_xNa_1−x)NbO₃ (x = 0.11 and 0.17) have been grown by the modified Bridgman method. The structure and chemical composition of the obtained crystals were determined by X-ray diffraction (XRD) and electron probe micro...

We conduct a numerical investigation into the stability of a quadruple-Q skyrmion crystal, a structure generated by the superposition of four spin density waves traveling in distinct directions within three-dimensional space, hosted on a centrosymmet...

The inherent nonpolarity of tetragonal lysozyme crystals excludes a ferroelectricity response. Herein, we present a demonstration of achieving measurable ferroelectricity in tetragonal lysozyme crystals through C₆₀ doping. Ferroelectric characterizat...

An overview of the chemical compounds forming the rare smectic T phases is presented with references to the historical context. Thermodynamics (transition temperatures, enthalpies) along with the factors (stereochemical constraints, electrostatic int...

In this study, we investigate the stability of a magnetic skyrmion crystal with short-period magnetic modulations in a centrosymmetric body-centered tetragonal system. By performing the simulated annealing for the spin model, incorporating the effect...

Dislocation-free tetragonal hen egg white (HEW) lysozyme crystals were grown from a seed crystal in a cell. The rates of tetragonal HEW lysozyme crystal growth normal to the (110) and (101) faces with and without a 1-MHz external electric field were...

We report the spatial structure of phosphoribosyl pyrophosphate synthetase 2 from the thermophilic bacterium Thermus thermophilus HB27 (TthPRPPS2) obtained at a 1.85 Å resolution using a diffraction set collected from rhombohedral crystals (space gro...

Single crystals of the new Ga-rich phases ReGa_~5(Sn), ReGa_~5(Pb) and ReGa_~5(Bi) were successfully obtained from the flux method. The new tetragonal phases crystallize in the space group P4/mnc (No. 128) with vertex-sharing capped Re₂@Ga₁₄ oblong chai...

A computational study promises insight into molecular crystals consisting of the tetrahedral form of N${}_4$ molecules (Td-N${}_4$). Here, our efforts are focused on theoretically predicting the existence of the molecular crystals consisting of Td-N${}_4$ molecules...

We report our numerical studies on the emergence of a double-Q checkerboard bubble crystal in centrosymmetric tetragonal magnets. The double-Q checkerboard bubble crystal is characterized by a fourfold-symmetric collinear spin configuration consistin...

The frequency and temperature dependence of dielectric properties of CH₃NH₃PbI₃ (MAPI) crystals have been studied and analyzed in connection with temperature-dependent structural studies. The obtained results bring arguments for the existence of ferr...

Tetragonal C₇, C₅N₂, and C₃N_4, characterized by mixed tetrahedral and trigonal atomic hybridizations, have been devised based on crystal chemistry rationale and structural optimization calculations within density functional theory (DFT). Substitution...

Novel superhard tetragonal carbon allotropes C₅, C₆, and C₇, characterized by the presence of sp³- and sp²-like carbon sites, have been predicted from crystal chemistry and extensively studied by quantum density functional theory (DFT) calculations....

Novel tetragonal (P4₂/mnm) boron pnictides BX (X = N, P, As, Sb, Bi) with chromium boride (crb) topology exhibiting a square B2X2 motif with resulting edge- and corner-sharing tetrahedra were predicted from crystal chemistry and extensively character...

The influence of the domain structure’s initial topology and its evolution on the hysteresis curves of tetragonal and rhombohedral polydomain structures of ferroelectroelastic materials is studied. Based on the analysis of electrical and mechan...

The parameters g-factor ($g_{\left|\right|}$ and $g_{\perp }$) together with the local structure of the Ce³⁺ center in BaWO4 single crystal (scheelite structure crystals) were theoretically investigated using a complete diagonalization procedure of energy matrix (...

The spin–Hamiltonian parameters g–factors ($g_{\left|\right|}$ and $g_{\perp }$) of the Ce³⁺ paramagnetic centers in BaWO₄: Ce and BaWO₄: Ce, Na single crystals with axial symmetry are investigated using the superposition model (SPM) via complete diagonalizat...

Materials of the ZrO₂-SiO₂ system were obtained by the sol-gel method applying two different types of ZrO₂ precursors: zirconium (IV) n-propoxide Zr(OC₃H₇)₄ and zirconium (IV) acetate Zr(OOC₂H₃)₄ (organic acetic acid salt) while commonly used tetraet...

X-ray diffraction (XRD) rocking-curves were measured for tetragonal hen egg white (HEW) lysozyme crystals grown with and without application of an external electric field, and the crystal quality was assessed according to the full width at half-maxim...

Single-crystalline fibers have distinct structures and optical properties comparing with the bulk crystals. In this article, two types of single-crystalline fibers of deuterated potassium dihydrogen phosphate (K(H_1−xD_x)₂PO_4, DKDP) are obtained...

In this study, single crystals of (K_1−xNa_x)NbO₃ are grown by the self-flux crystal growth method and their phase transitions are studied using a combination of Raman scattering and impedance spectroscopy. X-ray diffraction shows that single cry...

Lead-free (K_0.5Na_0.5)NbO₃-LiNbO₃ (KNN-LN) and (K_0.5Na_0.5)NbO₃-LiTaO₃ (KNN-LT) ferroelectric single crystals, with the dimensions of 11 ´ 11 ´ 5 mm³ and 5 ´ 5 ´ 3 mm³, were grown successfully using the top-seeded solution growth (TSSG) method, respec...

(K_0.5Na_0.5)NbO₃-based single crystals are of interest as high-performance lead-free piezoelectric materials, but conventional crystal growth methods have some disadvantages such as the requirement for expensive Pt crucibles and difficulty in controll...

In this study, a series of trivalent europium-doped tungstate and molybdate samples were synthesized using an improved sol-gel and high-temperature solid-state reaction method. The samples had different W/Mo ratios and were calcined at various temper...

Fully compensated ferrimagnets do not create any magnetic stray field and allow for a completely polarized current of charges. As a result, these alloys show promising prospects for applications as spintronic devices. In this paper, we investigated t...

BaTiO₃ (BT) is an essential material for many applications due to its dielectric, ferroelectric, and piezoelectric properties; nevertheless, it has been reported to possess a “critical size” in the nanoscale below which its outstanding pr...

Protein crystallization is usually conducted by using precipitants, although the “salting-out” phenomenon is still unclear and complex. Moreover, the addition of precipitants sometimes results in irreversible disordered precipitation of p...

CsCl-type cubic compound CeZn exhibits a paramagnetic (PM) to antiferromagnetic (AFM) first-order transition at T_N ~ 30 K accompanied by a simultaneous structural transition from cubic to tetragonal structure as temperature decreases. Applying the pr...

We report magnetism of tetragonal β-Fe₃Se₄ nanoplates controllably synthesized by thermal decomposition at 603 K of inorganic–organic (β-Fe₂Se₃)₄[Fe(tepa)] hybrid nanoplates (tepa = tetraethylenepentamine). (β-Fe₂Se₃)₄[Fe(tepa)]...

Tetrathiafulvalene (TTF), pentacene, and quarterthiophene with tert-butyl substituents are synthesized, and the crystal structures and the transistor properties are investigated. The tetracyanoquinodimethane (TCNQ) complex of tert-butyl TTF construct...

The effect of ceria doping of (ZrO₂)_1−x(Sm₂O₃)_x crystals on their phase composition, microhardness and fracture toughness was studied. The (ZrO₂)_0.995−x(Sm₂O₃)_x(CeO₂)_0.005 crystals (where x = 0.032, 0.037 and 0.04) were grown using direct...

In this work, we studied the phase composition, local structure and mechanical characteristics of ZrO₂ crystals partially stabilized with Y₂O₃ and co-doped with Nd₂O₃, CeO₂, Er₂O₃, Tb₂O₃ and Yb₂O₃. Crystals were grown by directional melt crystallizat...

The preparation of tetragonal barium titanate (BT) powders with uniform and suitable particle sizes is a significant prerequisite for ultra-thin and highly integrated multilayer ceramic capacitors (MLCCs). However, the balance of high tetragonality a...

Recently, the anomalous two-fold-symmetric in-plane anisotropy of superconducting states has been observed in a layered superconductor system, LaO_1−xF_xBiSSe (x = 0.1 and 0.5), with a tetragonal (four-fold symmetric) in-plane structure. To under...

Two new polymorphs of the phase-change material sodium acetate were characterized by single-crystal X-ray diffraction. A tetragonal form was found first. It converted to a orthorhombic form after measurement of a single crystal of the tetragonal form...

Protein crystals are intrinsically hydrated systems, and their structural integrity is strongly influenced by environmental humidity. Understanding the effects of relative humidity (RH) variation on crystal stability is therefore essential for both f...

Highly luminescent silver indium sulfide (AgInS₂) nanoparticles were synthesized by dropwise injection of a sulfur precursor solution into a cationic metal precursor solution. The two-step reaction including the formation of silver sulfide (Ag₂S) nan...

The extreme values of Young’s modulus for rhombic (orthorhombic) crystals using the necessary and sufficient conditions for the extremum of the function of two variables are analyzed herein. Seven stationary expressions of Young’s modulus are obtaine...

The magneto–elastic coupling effect correlates to the changes of moment and lattice upon magnetic phase transition. Here, we report that, in the pseudo-binary Laves-phase Tb_1-xDy_xCo₂ system (x = 0.0, 0.7, and 1.0), thermal expansion and magneto...

Relaxor-based ferroelectric single crystals Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (PMN-PT) have drawn much attention in the ferroelectric field because of their excellent piezoelectric properties and high electromechanical coupling coefficients (d₃₃~2000 pC/N, kt~...

K_0.5Na_0.5NbO₃ is considered as one of the most promising lead-free piezoelectric ceramics in the field of wearable electronics because of its excellent piezoelectric properties and environmental friendliness. In this work, the temperature-dependent l...

The achiral organic radical dinitrophenyl nitronyl nitroxide crystallizes in two enantiomorphs, both being chiral tetragonal space groups that are mirror images of each other. Muon-spin rotation experiments have been performed to study the magnetic p...

The high-k-based MOS-like capacitors are a promising approach for the domain of non-volatile memory devices, which currently is limited by SiO₂ technology and cannot face the rapid downsizing of the electronic device trend. In this paper, we prepare...

Effects of co-addition of CuBr₂ and NaCl to CH₃NH₃PbI₃(Cl) perovskite solar cells were investigated on the photovoltaic properties and microstructures. Short-circuit current densities and conversion efficiencies were improved by the simultaneous addi...

We demonstrate the application of confocal Raman microscopy (CRM) for nondestructive imaging of ferroelectric domains both at the surface and in the bulk of lead magnesium niobate-lead titanate (PMN-PT) ferroelectric single crystals. The studied mode...

Piezoelectric properties are of significant importance to medical ultrasound, actuators, sensors, and countless other device applications. The mechanism of piezoelectric properties can be deeply understood in light of structure evolutions. In this pa...

We measured the thermal conductivity (λ) and thermal diffusivity (α) of tetragonal hen egg-white lysozyme (HEWL) crystals by the transient short-hot wire method. The crystals were grown by two different methods: Magnetically levitated cr...

We investigate the stability tendency of a magnetic skyrmion crystal in noncentrosymmetric tetragonal systems with the Dzyaloshinskii–Moriya interaction. We show that the stability region of the square skyrmion crystal on a square lattice depen...