41 results about "Crystal chemistry" patented technology

The invention provides a preparation method and application of a compound cesium ammonium fluoborate and a cesium ammonium fluoborate nonlinear optical crystal. The chemical formula of the compound is CsNH4B8O12F2; the chemical formula of the crystal is CsNH4B8O12F2, the crystal belongs to a trigonal system, the space group is P321, and the unit cell parameters are as follows: a = b = 6.5858 (4) + / -0.02, c = 7.8163 (6) + / -0.02, alpha = beta = 90 degrees, gamma = 120 degrees and Z = 1. The crystal is grown by adopting a vacuum high-temperature solution method, a room-temperature solution method or a hydrothermal method, and the ultraviolet transmission cut-off edge of the crystal is lower than 190 nm. The nonlinear optical effect of the crystal is about 2.5 times of that of KH2PO4 (KDP), and the shortest I-type phase matching wavelength is 175.5 nm. The crystal has the advantages of simple preparation method, low toxicity of used initial raw materials, small harm to human bodies, stable physical and chemical properties, uniaxial crystal, easiness in application and the like. The method can be widely applied to nonlinear optical devices such as ultraviolet and deep ultraviolet all-solid-state lasers, optical parametric oscillators and the like.

The invention relates to a Cs3Bi2I9 single-crystal material with double heat transfer operation parameters as well as a preparation method and application thereof, and belongs to the technical field of single-crystal materials. The preparation method comprises the following steps: uniformly mixing and grinding CsI and BiI3 according to a stoichiometric ratio, transferring into a quartz tube, vacuumizing and packaging, and sequentially carrying out high-temperature melting, quenching and annealing to obtain a Cs3Bi2I9 polycrystalline cast ingot of which the density is not less than 97%; placing the Cs3Bi2I9 polycrystalline cast ingot in a sealed quartz tube, placing the sealed quartz tube in which the Cs3Bi2I9 polycrystalline cast ingot is packaged in a vertical temperature gradient furnace, melting at high temperature, and cooling to room temperature, thereby obtaining the Cs3Bi2I9 single crystal material with the double heat transfer operation mode. Compared with the prior art, the Cs3Bi2I9 single crystal material with a unique double-heat transport behavior is innovatively prepared, a new design idea is provided for regulating and controlling heat transport through a crystal chemical means, and a new path is opened up for developing an anisotropic thermoelectric material with a heat management function.

This invention belongs to the field of long afterglow luminescent materials technology, and specifically discloses an ultra-broad spectrum Cs2CdCl4:xPb 2+ Long-afterglow luminescent materials, their preparation methods and applications, including Cs₂CdCl₄:xPb 2+ Long-afterglow luminescent materials are based on Cs₂CdCl₄ and contain Pb 2+ It is a luminescent recombination center with the general chemical formula Cs₂CdCl₄:xPb 2+ Where 0.001 ≤ x ≤ 0.1. The Cs₂CdCl₄:xPb of this invention... 2+ The long-afterglow luminescent material exhibits high crystal chemical stability and can be effectively excited by 254nm ultraviolet light or X-rays, possessing a long-afterglow luminescence spectrum across an ultrawide wavelength range from UVB to visible light, with a long afterglow duration. It does not require harsh synthesis conditions involving high pressure and reduction; the synthesis can be carried out under ambient pressure using a solvothermal method and Cs₂CdCl₄:xPb. 2+ The required chemical raw materials can be used to synthesize Cs₂CdCl₄:xPb 2+ Long afterglow luminescent materials; Cs₂CdCl₄:xPb 2+ Long-afterglow luminescent materials are simple to prepare and can be mass-produced industrially; Cs₂CdCl₄:xPb 2+ Long-afterglow luminescent materials can be applied to fields such as optical anti-counterfeiting and wearable devices, and are unaffected by visible light.

The invention discloses an organic and inorganic compound crystal (H11C4N2) CdI3 as well as a preparation method and application thereof. The organic and inorganic compound crystal is a hybrid crystal, the chemical formula is (H11C4N2) CdI3, the organic and inorganic compound crystal belongs to a monoclinic system, the space group is Cc, and the cell parameters are as follows: a = 14.36-14.38, b = 7.13-7.15, c = 13.77-13.79, alpha = gamma = 90 degrees, beta = 121.2-121.4 degrees, and Z = 4. The crystal is prepared by a hydrothermal method. The organic-inorganic hybrid crystal has excellent second-order nonlinear optical performance, can output very strong 532 nm laser under 1064 nm laser irradiation, has a powder SHG coefficient 6 times that of KH2PO4 (KDP), can realize phase matching, and is a second-order nonlinear optical material with potential application value.

The application belongs to the field of nonlinear optical materials, and relates to a kind of ultraviolet nonlinear optical crystal material and its preparation method and application.The crystal chemical formula of the ultraviolet nonlinear optical crystal material is Zn (C5H4NO) 2, C5H4NO represents 4-hydroxy pyridine, 4-hydroxy pyridine is combined with Zn 2+ Form [ZnN2O2] tetrahedron by coordination bond;The crystal belongs to the orthorhombic system, and the space group is Fdd2.The band gap of the ultraviolet nonlinear optical crystal material is 4.40eV, the second harmonic generation is as high as 13.6xKDP, the birefringence Δn at 532nm wavelength is 0.073, the birefringence Δn at 1064nm wavelength is 0.074, and it shows photoluminescence characteristics, has phosphorescence with a lifetime of 558ms under the excitation light with a wavelength of 330-420nm, and blue afterglow with a naked eye visible and a duration of 5s.In addition, the ultraviolet nonlinear optical crystal material has strong water resistance, thermal stability and environmental stability, and has good application prospect in the field of nonlinear optical materials.

The invention discloses a compound rubidium antimony aluminum silicate and a preparation method and application of a rubidium antimony aluminum silicate nonlinear optical crystal, the chemical formula of the compound rubidium antimony aluminum silicate and the crystal of the compound rubidium antimony aluminum silicate is Rb5Sb4AlSi4O22, the crystal belongs to an orthorhombic system, the space group is that the cell parameter Z is 2, and the molecular weight is 1405.67. The compound rubidium antimony aluminum silicate is synthesized by adopting a high-temperature solid-phase reaction method, the rubidium antimony aluminum silicate nonlinear optical crystal grows by adopting a high-temperature solution method, the preparation method is simple, convenient and low in cost, and the obtained crystal has the advantages of wide light transmission range, stable physical and chemical properties, easiness in storage and the like, and can be used for preparing nonlinear optical devices.

The present application relates to a kind of compound potassium rubidium borophosphate and a kind of preparation method and purposes of potassium rubidium borophosphate nonlinear optical crystal, the chemical formula of the compound potassium rubidium borophosphate and its crystal is K 0.9 Rb 2.1 B8PO 16 Crystal belongs to monoclinic system, space group Cc, cell parameter Z=4, molecular weight is 586.16. Compound potassium rubidium borophosphate is synthesized using high-temperature solid-phase reaction method, and potassium rubidium borophosphate nonlinear optical crystal is grown using high-temperature melt method. The preparation method is simple and low in cost. The obtained crystal has a wide light transmission range, stable physical and chemical properties, and can be used to prepare nonlinear optical devices.

This invention relates to a series of alkali metal rare earth chalcogenides and a series of alkali metal rare earth chalcogenide nonlinear optical crystals, their preparation methods, and their applications. The general chemical formula for both the series of halides and the nonlinear optical crystals is A3Ln. 11 Ga 19 Q 45 X3, where A = K, Rb, Cs; Ln = La, Pr, Nd; Q = S, Se; X = Cl, Br, I, all belong to the hexagonal crystal system with space group and cell parameter Z = 1. This series of halides is synthesized using a high-temperature solid-state method, while this series of nonlinear optical crystals is grown using a high-temperature solution method or the Bridgman process. This material can be used to manufacture second harmonic generators, up- and down-frequency converters, optical parametric oscillators, etc.

The invention relates to an alkali metal composite molybdate compound, an alkali metal composite molybdate nonlinear optical crystal and a preparation method and application of the alkali metal composite molybdate compound and the alkali metal composite molybdate nonlinear optical crystal, the chemical general formulas of the compound and the crystal are KAMo2O7, A is Rb or Cs, the crystal belongs to an orthorhombic system, the space group is Ama2, and the cell parameter # imgabs0 # # imgabs1 # Z is 4. The alkali metal composite molybdate compound is synthesized by adopting a solid-phase reaction method, the nonlinear optical crystal grows by adopting a high-temperature melt method or an aqueous solution method, and the nonlinear optical crystal can be used for manufacturing a second harmonic generator, an upper frequency converter, a lower frequency converter, an optical parametric oscillator and the like.

The invention discloses purple light excited red oxynitride glass ceramic as well as a preparation method and application thereof, and belongs to the technical field of fluorescent glass ceramic. The crystal chemical general formula of the red-light oxynitride glass ceramic is Mg2Al4Si5 (ON) 18: Eu < 2 + >, the crystal structure belongs to a hexagonal crystal system, and the space group is P6 / mcc. According to the preparation method, the emission spectrum red shift of the Eu < 2 + > ion doped Mg2Al4Si5 (ON) 18 fluorescent material is induced through the regulation and control means of partial nitridation, the red light waveband coverage range is widened, the red light color purity is effectively improved, the preparation method of melting cooling and in-situ crystallization is adopted, the prepared material is an inorganic block material, the thermal stability and chemical stability of the material are improved, and the preparation method is suitable for industrial production. The material can be applied to the fields of white light LED devices, laser illumination display, plant illumination, optical medical treatment and the like.

The invention relates to an alkali metal oxalofluoroborate nonlinear optical crystal, a preparation method and application thereof. The crystal has a general chemical formula of M3[B3O3F2(OH)(C2O4)][B3O3F2(OH)2], where M=K or Rb, and has molecular formulas of K3[B3O3F2(OH)(C2O4)][B3O3F2(OH)2] or Rb3[B3O3F2(OH)(C2O4)][B3O3F2(OH)2], respectively. The molecular weights are 632.31 and 493.20, respectively. The crystal is grown by a hydrothermal method or a room temperature solution method. The cutoff edge of the crystal obtained by the method is less than 200 nm. The preparation method of the crystal is simple, the physicochemical properties are stable, and the crystal can be used as a short-wavelength ultraviolet nonlinear optical crystal in an all-solid-state laser.

The present invention provides a compound, calcium guanidine nitrate, and a birefringent calcium guanidine nitrate crystal, as well as a preparation method and use thereof. The chemical formula of the compound is [C(NH2)3]2Ca(NO3)4(H2O)2, the molecular weight is 444.33, and the compound is prepared by a solvent thermal method. The crystal chemical formula is [C(NH2)3]2Ca(NO3)4(H2O)2, the molecular weight is 444.33, and the crystal belongs to the monoclinic system with a space group of C 2 / c , the unit cell parameters are a =20.319(3)Å, b =6.5717(8)Å, c =14.2195(16)Å, α =90°, β =116.399(5)°, c =90°, the unit cell volume is 1700.8(4)Å 3 , with a transmittance range of 281-1600 nm and a birefringence index between 0.152 (1064 nm) and 0.23 (281 nm). Grown using a room-temperature aqueous solution method, the resulting birefringent crystals possess moderate mechanical hardness, are easily cut, polished, and stored, and are easy to grow under simple growth conditions. They are insoluble in water, non-deliquescent, and stable in air. They exhibit a wide transmittance range and birefringence, and can be used to fabricate polarization beam splitters, phase delay devices, and electro-optical modulators.

The invention discloses an imidazolyl zinc complex crystal and application thereof as an ester hydrolysis mimic enzyme, and belongs to the technical field of metal organic complexes. According to the imidazolyl zinc complex crystal, the chemical molecular formula of the imidazolyl zinc complex crystal is [Zn (L)] (CH3CH2OH), L represents L-carnosine, and an asymmetric structural unit in the imidazolyl zinc complex crystal comprises a Zn (II), a deprotonated L-carnosine ligand and an ethanol molecule; the crystal structure of the imidazolyl zinc complex crystal is a monoclinic system P21 space group. Zinc ions and L-carnosine are coordinated to form an imidazolyl zinc complex crystal, and the imidazolyl zinc complex crystal is used as the ester hydrolysis mimic enzyme, has high catalytic activity, and can effectively solve the technical problems of relatively low catalytic efficiency and stability of the existing ester hydrolysis mimic enzyme.

The invention relates to a fluorinated biuret borate nonlinear optical crystal and a preparation method and application thereof, the chemical formula of the crystal is [C2N3O2BF2H5] [BF4], the molecular weight is 238.71, and the crystal is prepared by a hydrothermal method or a room temperature solution method; the crystal belongs to a monoclinic system, the space group is P21, and the cell parameters are as follows: a = 6.0521 (11), b = 9.4651 (18), c = 7.1398 (12), beta = 91.267 (7), Z = 2, and V = 408.90 (13) 3. The [C2N3O2BF2H5] [BF4] nonlinear optical crystal obtained by the method is used for manufacturing a second harmonic generator, an upper frequency converter, a lower frequency converter, an optical parametric oscillator and the like; meanwhile, the crystal can also be used as a birefringent crystal for manufacturing a refractive index modulator, a phase modulator and a polarization device.

This invention relates to a compound strontium borate nitrate and a strontium borate nitrate nonlinear optical crystal, as well as their preparation methods and uses. The chemical formula of the compound is Sr3B9O. 16 (NO3), with a molecular weight of 678.16, was prepared using a vacuum-sealed tube method; the chemical formula of this crystal is Sr3B9O. 16 (NO3), with a molecular weight of 678.16, belongs to the monoclinic crystal system and has a space group of Cc The unit cell parameters are a =11.2574(9)Å, b =6.6400(9)Å, c =18.1027(13)Å, Z=4, V=1348.9(2)Å 3 It is prepared using a high-temperature melt method or hydrothermal method under vacuum sealing conditions. Its nonlinear optical effect is approximately three times that of KDP, and its birefringence is 0.088@546 nm. This method has advantages such as simple preparation, short growth cycle, low toxicity of starting materials, and minimal harm to humans. Sr3B9O obtained by the method described in this invention... 16 (NO3) Nonlinear optical crystals have stable physicochemical properties, large nonlinear effects, and can be applied to phase-matching wavelengths in the ultraviolet band. They can be widely used in nonlinear optical devices such as frequency doubling converters and optical parametric oscillators.

The invention belongs to the field of organic-inorganic hybrid functional crystal materials, and relates to an inorganic-organic hybrid three-dimensional crystal as well as a preparation method and application thereof, raw materials containing hydroiodic acid, a protonated organic molecular cage C-D3T2 and a lead source are mixed with a solvent, and the inorganic-organic hybrid crystal is obtained through solvothermal reaction. The chemical formula of the prepared crystal is {[C-D3T2] [Pb5I14 (I3)]}. I. 6H2O; wherein the molecular formula of the C-D3T2 organic cage is H6 [C36H54N8]. The crystal is of a host-guest body structure assembled by a three-dimensional inorganic framework [(Pb5I14) I3] n5n-and a C-D3T2 molecular cage through electrostatic interaction and belongs to a monoclinic system, and the space group is C2 / c. The crystal is of a three-dimensional nested structure constructed by an organic molecular cage and inorganic lead iodide for the first time, and has certain application potential in the field of photothermal conversion.

The invention provides a cesium potassium fluoborate nonlinear optical crystal and a preparation method and application thereof, the chemical formula of the crystal is Cs4.8K5.2 B13O15F19, the molecular weight is 1582.8, the crystal belongs to a trigonal system, the space group is R3m, the cell parameters are as follows: a = 14.2606 (8), b = 14.2606 (8), c = 14.7689 (10), alpha = 90 degrees, beta = 90 degrees, gamma = 120 degrees, the unit cell volume is 2601.1 (3) 3, the number z of molecules in the cell is 3, the ultraviolet absorption edge is less than 200 nm, and the crystal has a nonlinear optical effect. And the frequency-doubled effect of the powder is about 0.17 times that of KDP (potassium dihydrogen phosphate). The crystal is grown by adopting a high-temperature solution method and a vacuum packaging method. The crystal has good chemical stability and can be used for manufacturing ultraviolet nonlinear optical devices.

The present invention provides a compound yttrium lead rubidium borate and a yttrium lead rubidium borate nonlinear optical crystal and a preparation method and use thereof. The chemical formula of the compound is Rb7PbY2B 15 O 30 , molecular weight is 1625.45, it is prepared by solid phase synthesis or vacuum packaging method, the crystal chemical formula is Rb7PbY2B 15 O 30 , molecular weight is 1625.45, belongs to the trigonal system, and the space group is R 32, the unit cell parameters are a =13.4642(3)Å, b =13.4642(3)Å, c =15.2917(8)Å, α =90°, β =90°, c =120°, the unit cell volume is 2400.18 Å 3 , using melt method, high temperature melt method or vacuum packaging method to grow crystals, the Rb7PbY2B obtained by this method 15 O 30 Nonlinear optical crystal, the powder frequency-doubled effect of the crystal is about 1.3 times that of KH2PO4 (KDP), the ultraviolet cutoff edge is lower than 300 nm, and the physical and chemical properties are stable. It can be used as a short-wavelength ultraviolet nonlinear optical crystal in all-solid-state lasers.

The invention discloses blue-light microcrystalline glass capable of being excited by purple light as well as a preparation method and application of the blue-light microcrystalline glass, and belongs to the technical field of fluorescent materials. The general chemical formula of crystals in the blue-light microcrystalline glass is Li (Sr, Ba) 2Al (PO4) 3: Eu < 2 + >, the crystal structure belongs to a monoclinic system, the space group is P21 / n, the blue-light microcrystalline glass is prepared from the following material components in mole fraction: 10-60 mol% of Li2CO3, 20-50 mol% of SrCO3, 0-50 mol% of BaCO3, 5-30 mol% of Al2O3, 20-60 mol% of P2O5, 0.005-10 mol% of Eu2O3 and 5-30 mol% of B2O3, and the total mole ratio of the material components is 100 mol%. The blue-light microcrystalline glass can be applied to preparation of white-light LED devices.

This invention relates to the field of crystal chemistry, and more particularly to a crystalline form OA1 of ellastatin oxalate, its preparation method, pharmaceutical composition, and applications. The crystalline form OA1 of ellastatin oxalate, when subjected to Cu-Kα radiation, exhibits an X-ray powder diffraction pattern including two or more 2θ values ​​selected from the group consisting of: 8.9±0.2°, 9.6±0.2°, 12.0±0.2°, 12.7±0.2°, 18.2±0.2°, 19.4±0.2°, and 24.2±0.2°. The crystalline form OA1 of ellastatin oxalate provided by this invention offers advantages in terms of stability, hygroscopicity, melting point, process scale-up feasibility, purification effect, solubility, in vitro and in vivo dissolution, bioavailability, compressibility, flowability, formulation quality, and processing performance, providing a better option for the development of drugs containing ellastatin oxalate.

The invention relates to a cobalt-based ferroelectric single-molecule magnet molecular crystal and a preparation method and application thereof, and belongs to the technical field of molecule-based magnetic materials. The chemical formula of the cobalt-based ferroelectric single-molecular magnet molecular crystal is [(CH3) 3S] 4 [Co (NCBH3) 6]. According to the invention, through the rational design of the molecular structure of an A4 [M (NCX) 6] type compound, the ordered-disordered phase change of organic cations is regulated and controlled to induce the symmetry breaking of the crystal so as to generate ferroelectricity; meanwhile, the transition metal center is endowed with strong magnetic anisotropy through ligand field engineering, so that the single-molecule magnet characteristic is realized, and the cobalt-based molecular crystal with the single-phase coexisting ferroelectricity and the single-molecule magnet characteristic is finally obtained; the problem that an existing A4 [M (NCX) 6] type compound cannot synergistically integrate ferroelectricity and the characteristics of a single-molecule magnet is solved.

The invention discloses a high-stability thio polar metal halide perovskite crystal and a preparation method and application thereof, and belongs to the technical field of artificial crystal materials in the field of functional crystal materials. The chemical formula of the crystal is (4-SP) 4Pb3Br10. 2H2O, the crystal belongs to an orthorhombic system, the space group is Aea2, the cell parameters are as follows: alpha = 90 degrees, beta = 90 degrees, gamma = 90 degrees, Z = 4, and the density is 2.842 g / cm < 3 >. The preparation method comprises the following steps: mixing 4-aminothiophenol and lead acetate trihydrate, adding an HBr aqueous solution, heating and stirring to obtain a colorless clear solution, and performing post-treatment to obtain the crystal. The crystal has application potential in an X-ray detector.

This invention relates to a Cs3Bi2I9 single-crystal material with dual thermal transport behavior, its preparation method, and its applications, belonging to the field of single-crystal material technology. The preparation method includes the following steps: CsI and BiI3 are mixed and ground uniformly according to a stoichiometric ratio, then transferred to a quartz tube, vacuum-sealed, and sequentially subjected to high-temperature melting, quenching, and annealing to obtain a Cs3Bi2I9 polycrystalline ingot with a density of not less than 97%; the Cs3Bi2I9 polycrystalline ingot is placed in a sealed quartz tube, and the sealed quartz tube containing the Cs3Bi2I9 polycrystalline ingot is placed in a vertical temperature gradient furnace, first melted at high temperature, and then cooled to room temperature to obtain the Cs3Bi2I9 single-crystal material with dual thermal transport behavior. Compared with the prior art, this invention innovatively produces a Cs3Bi2I9 single-crystal material with unique dual thermal transport behavior, providing a new design concept for controlling heat transfer through crystal chemistry, and also opening up a new path for developing anisotropic thermoelectric materials with thermal management functions.

This invention relates to a compound sodium vanadium selenite and a sodium vanadium selenite optical crystal, as well as their preparation methods and uses. The compound has the chemical formula NaVSeO5 and a molecular weight of 232.89, and is prepared using a vacuum encapsulation method. The crystal has the chemical formula NaVSeO5 and a molecular weight of 232.89. The crystal belongs to the monoclinic crystal system and has a space group of [space group missing]. C 2 / c The unit cell parameters are a =18.234(3)Å, b= 3.8381(6)Å, c= 12.416(2)Å, α =90°, β =112.421(7)°, γ = 0.5 90°, V=803.2(2)Å 3 Z=8. The crystal is grown using the sealed molten salt method, the high-temperature melt method, or the vacuum tube sealing method. At a wavelength of 1064 nm, the crystal has a birefringence Δn=0.12, good chemical stability, moderate mechanical hardness, and is easy to cut, polish, process, and store. It is insoluble in water and does not deliquesce, making it suitable for fabricating optical communication components or various polarizing prisms, phase delay devices, and electro-optic modulation devices, such as Glan prisms, polarization beam splitters, compensators, optical isolators, circulators, and optical modulators. It plays an important role in the fields of optics and communications.

This invention relates to the compounds strontium lanthanum chloroborate and barium lanthanum chloroborate, as well as nonlinear optical crystals of strontium lanthanum chloroborate and barium lanthanum chloroborate, their preparation methods, and their uses. The general chemical formula for both the compounds and crystals is A3La4B3O. 13 Cl, where A = Sr, Ba, space group P63, belongs to the hexagonal crystal system, and cell parameter Z = 2. The compounds lanthanum strontium chloroborate and lanthanum barium chloroborate are synthesized by a solid-state reaction method. The nonlinear optical crystals of lanthanum strontium chloroborate and lanthanum barium chloroborate are grown using a high-temperature melt method. This material can be used to manufacture second harmonic generators, up-down frequency converters, optical parametric oscillators, etc.

The invention discloses a chemical mechanical polishing solution for CsPbBr3 crystal polishing and application, and belongs to the technical field of crystal chemical mechanical polishing. The polishing solution is composed of absolute ethyl alcohol, silicone oil, deionized water, a dispersing agent, hydrogen bromide and aluminum oxide, wherein the absolute ethyl alcohol, the silicone oil, the deionized water, the dispersing agent and the hydrogen bromide are mixed according to the volume ratio of 33: 59.2: 7: 0.6: 0.2 to form a solution I; the mass ratio of the solution I to the aluminum oxide is 10: 1. By using the polishing solution, the mechanical action and the chemical corrosion rate of the CsPbBr3 crystal in the chemical mechanical polishing process can be effectively balanced, and the damage to the crystal in the chemical mechanical polishing process is reduced; according to the polishing solution, the surface roughness, scratch density and depth generated in the CsPbBr3 crystal chemical mechanical polishing process are greatly reduced, so that the CsPbBr3 crystal chemical mechanical polishing treatment process is efficient and stable, the CsPbBr3 crystal chemical mechanical polishing quality is greatly improved, a high-quality polished surface is obtained, the physical and electrical properties of the crystal can be remarkably improved, and the quality of the CsPbBr3 crystal is improved. The practicability is high.

The invention relates to the technical field of photoelectric functional materials, in particular to a rare earth luminescent material with chiral nano morphology and a preparation method thereof. The rare earth luminescent material disclosed by the invention is of a micron-scale hexagonal prism structure, and spiral chiral patterns are highlighted on the top surface and the bottom surface of the rare earth luminescent material; the chemical composition of the crystal is a hexagonal phase b-NaYF4: E, wherein E is selected from at least one of Yb < 3 + >, Er < 3 + >, Nd < 3 + > and Eu < 3 + >; according to the invention, the coordination effect of oleate anions and rare earth cations on the microcrystalline surface is adjusted by optimizing the hydrothermal synthesis reaction conditions of oleic acid, so that the microcrystalline luminescent material with the spiral surface appearance is obtained; the preparation method is simple to operate and easy to control, the prepared product is stable, the circular polarization luminescence performance is remarkable, and the preparation method is expected to become an important basis for research and application directions of chiral morphology synthesis of inorganic crystals, circular polarization light three-dimensional imaging, circular polarization optical communication and the like.

The invention discloses a potassium boron niobate transparent ferroelectric crystal and a growth method and application thereof. The chemical formula of the transparent ferroelectric crystal is K3Nb3B2O12, the transparent ferroelectric crystal belongs to a trigonal system, and the space group of the transparent ferroelectric crystal is P31m. The transmission range of the potassium boron niobate transparent ferroelectric crystal is 330-2500nm, the spontaneous polarization intensity is 4.0 [mu] C / cm < 2 >, the coercive field is 5.8 kV / cm, and the potassium boron niobate transparent ferroelectric crystal has wide and high optical transmission, stable physical and chemical properties and thermal properties, is not easy to deliquesce, has good mechanical properties, is easy to process, and is an excellent transparent ferroelectric crystal material.

This invention belongs to the fields of chemical drug synthesis and crystal chemistry, and relates to a crystal form of dimenhydrinate and its preparation method. Crude dimenhydrinate is mixed with an organic solvent, heated, and stirred to form a slurry, obtaining a dispersion. The dispersion is then cooled and stirred to induce crystallization. The crystallization system is subjected to solid-liquid separation, and the solid is dried to obtain crystal form B dimenhydrinate. The new crystal form of dimenhydrinate provided by this invention has the characteristics of low liquid phase related substances content, with the maximum single impurity less than 0.03% and the total impurities less than 0.05%. The preparation method provided by this invention is simple and safe to operate, requires no special equipment, and achieves a yield of over 95%.

The invention provides a compound ammonium potassium fluoborate, an ammonium potassium fluoborate nonlinear optical crystal and a preparation method and application thereof. The chemical formula of the compound is Kx (NH4) 2-xB8O12F2 (x is more than 0 and less than 2), the chemical formula of the crystal is Kx (NH4) 2-xB8O12F2, the crystal belongs to an orthorhombic system, the space group is Pna21, and the unit cell parameters are as follows: a = 7.5880 (7) + / -0.02, b = 11.2019 (10) + / -0.02, c = 6.5989 (6) + / -0.02, alpha = beta = gamma = 90 degrees, and Z = 2. The crystal is grown by adopting a vacuum high-temperature solution method, a room-temperature solution method or a hydrothermal method, and the ultraviolet transmission cut-off edge of the crystal is lower than 190 nm. The nonlinear optical effect of the crystal is about 2.8 times that of KH2PO4 (KDP), and the shortest I-type phase matching wavelength is about 165.5 nm. The crystal has the advantages of being simple in preparation method, low in toxicity of used starting raw materials, small in harm to human bodies, not prone to deliquescence, good in thermal stability, easy to apply and the like. The method can be widely applied to nonlinear optical devices such as ultraviolet and deep ultraviolet all-solid-state lasers, optical parametric oscillators and the like.