大功率CO_2激光器非平衡态合成单晶的研究

用大功率CO_2激光器非平衡态制取单晶的方法从固态混合物熔体(Al_2O 3-10mol％Cr_2O)3)-M_0,Al_2O_3-(50,60,80)mol％WO_3中合成了可分离的M_0O_3,Al_2O_3及Al_2O_3·3WO_3,Al_2O_3·4WO_3单晶体,分析表明,激光非平衡态下生成的单晶与平衡态下生长的同种物质单晶在微观参量及外观上一致,而非平衡态下激光合成的晶体可以是平衡态下由相同的反应物难于生成的物质。

人造大单晶金刚石合成技术及应用研究现状

随着近几年人造金刚石技术研究的再次发展,大单晶金刚石合成技术成为相关研究者新的研究方向。本文结合当前人造金刚石合成现状,详细介绍了金刚石的合成技术发展,各大研究机构的研究进度,生产设备及合成方法。大单晶金刚石的应用情况等。

重稀土氟氧化物单晶高压合成及结构解析

利用高温高压技术合成了非化学式计量比HREEO_(1-x)F_(1+2x)型重稀土氟氧化物的单晶(HREE=Gd,Ho,Tm,Yb;x=0.0269、0.0066、0.0502、0.1078):GdO_(0.9731±0.0049)F_(1.0538±0.0099)、HoO_(0.9934±0.0054)F_(1.0132±0.0109)、TmO_(0.9498±0.0146)F_(1.1005±0.0292)、YbO_(0.8922±0.0028)F_(1.2157±0.0054),并利用拉曼光谱及单晶X射线衍射(SCXRD)测定了它们的拉曼光谱特征和晶体结构。拉曼光谱结果显示,合成的非化学式计量比重稀土氟氧化物的拉曼谱整体相似,都有4个强度较高的拉曼特征峰,随着原子序数的增加拉曼位移呈现规律性的变化。SCXRD结果显示,合成的非化学式计量比重稀土氟氧化物均属于正交晶系,其中,GdO_(0.9731)F_(1.0538)为Pbcm空间群,而后3个属于Aem2空间群。其中GdO_(0.9731)F_(1.0538)的晶胞参数为a=0.5334(3)nm,b=0.5474(1)nm,c=3.2786(2)nm;HoO_(0.9934)F_(1.0132)晶胞参数为a=0.5438(1)nm,b=3.8661(1)nm,c=0.5536(1)nm;TmO_(0.9498)F_(1.1005)的晶胞参数为a=0.5369(1)nm,b=3.8340(1)nm,c=0.5492(1)nm;YbO_(0.8922)F_(1.2157)的晶胞参数为a=0.5349(1)nm,b=4.9006(2)nm,c=0.5469(1)nm。晶体单胞是由n个类萤石结构的亚晶胞沿b或c轴方向堆叠而成,其中有部分亚晶胞被O^(2-)离子替代或被F^(-)、O^(2-)共同占据,形成6、7或8配位的类萤石亚晶胞结构,6和7配位的亚晶胞会发生结构上的畸变而8配位亚晶胞与萤石结构的亚晶胞基本一致。

金刚石合成技术与研究现状简介

随着近几年人造金刚石技术研究的深入发展,大单晶金刚石合成技术得到了广泛关注,成为研究热点。本文结合当前人造金刚石合成现状,着重介绍了金刚石的合成技术发展,包括生产设备、合成方法、及主要研究机构的研究进度,并讨论了大单晶金刚石的应用研究进展。

人工合成橄榄石单晶方法综述

橄榄石是上地幔的主要造岩矿物,研究橄榄石在高温高压下的物理化学性质是了解地幔对流、板块运动等地球动力学过程的基础.一些研究橄榄石物理化学性质的实验需要用到橄榄石单晶,例如在实验室中进行的变形实验,无论是双轴压缩、三轴压缩、简单剪切,还是扭转变形实验等等.近年来,水对橄榄石蠕变性质的影响被广泛关注,橄榄石的含水测量也需要用到大尺寸的橄榄石单晶.除了实验室需要大晶体,合成晶体也是新材料领域的研究热点和发展前沿,目前国内外人工合成单晶的方法包括从固相、液相、气相以及从熔体中合成晶体.在人工合成橄榄石单晶方面,目前主要使用的方法包括提拉法、浮区法和烧结法.本文综述了从固相、液相、气相以及从熔体中合成晶体的方法,详细介绍了人工合成橄榄石单晶所采用的提拉法、浮区法和烧结法等三种方法的原理与合成过程,讨论了不同方法的优缺点,其中烧结法合成单晶需要的时间短,但是对温度以及实验的氧化还原环境要求较高;浮区法生长大的单晶耗时短、可以得到大尺寸的单晶,但对工艺技术要求高;提拉法可以通过籽晶的取向来制备不同晶体取向的单晶,过程容易控制,但是由于使用坩埚而容易污染,不适用于对于固态下有相变的晶体.通过以上研究,本文提出了以后生长大尺寸橄榄石单晶的可能途径,希望对橄榄石单晶的制备方面工作提供参考.

Synthesis and Structure of Zinc 3-Hydroxy-2-mercaptopyridine Complex, Zn(C_5H_4NOS)_2

The zinc 3-hydroxy-2-mercaptopyridine complex was prepared by self-assemby reaction of Zn(NO3)2 and 3-hydroxy-2-mercaptopyridine (hmp). Single-crystal X-ray diffraction analysis indicates that it crystallizes in a tetragonal system, space group (No. 122) with a = 13.4562(6), c = 13.6860(8) , V = 2478.1(2) 3, Z = 8, Mr = 317.67, Dc = 1.703 g/cm3, m(Mo-Ka) = 2.308 mm-1 and F(000) = 1280. R = 0.0289 and wR = 0.0676 for 1040 observed reflections (I > 2s(I)). The crystal structure consists of a neutral molecule with a distorted tetrahedral cis-ZnS2O2 core, in which the mononuclear Zn2+ ion is coordinated by two O and two S atoms from two hmp ligands with the average bond distances of 2.301(1) ?for ZnS and 1.986(3) ?for ZnO. The 1H . NMR and IR spectra of the compound are discussed.

超硬材料专利信息10则

名称：单晶合成金刚石材料中的位错设计摘要：本发明涉及一种单晶CVD合成金刚石层，包括非平行的位错阵列，其中当在X射线形貌断面图中观察或在发光条件下观察时，非平行的位错阵列包含形成一组相互交叉的位错的多个位错。

Synthesis and Crystal Structure of Potassium Crown Ether Tetrathiosquarate

Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis（potassium{18-crown-6}）（3-cyclobutene-1,2-dithione-3,4-dithiolate） [K（C12H2406）]2（CnS4）. The crystal structure determination （monoclinic, P 2t/n, a = 12.2095（8） A, b = 11.3263（8） A, c = 14.0552（7） A, fl = 101.032（3）~, Z = 2） shows the presence of C4S42 - ions with almost undistorted D4h symmetry having C-C bond lengths of 1.442（10） A and 1.478（8） A and C-S bond lengths of 1.651（8） A and 1.664（7） A. Since the K＋ ions are shielded in a half-spherical way by the crown ether ligands, the crystal structures is built of centrosymmetric molecular entities [（18-crown-6）K（C4S4）K（18-crown-6）]. The K＋ ions have eight of coordination number, C4S42- acts as a chelating and bridging ligand towards two K＋ with K-S distances of 3.434（2） A and 3.380（2） A.

Synthesis and Crystal Structure of a New Chain Coordination Polymer [Cu(inio)_2(H_2O)]_∞(Inio = Isonicotinic Acid N-Oxide)

A new Cu(Ⅱ) coordination polymer [Cu(inio)2(H2O)] (inio = isonicotinic acid N-oxide) with chemical formula C12H10CuN2O7 was prepared and its crystal structure has been determined by X-ray analysis. The complex crystallizes in the monoclinic system, space group C2/c with a = 12.455(3), b = 6.202(1), c = 16.555(3) ? b = 106.776(3), V = 1224.3(4) 3, Z = 4, Mr = 357.76, Dc =1.941 g/cm3, m(MoKa) = 1.827 mm-1, F(000) = 724, R = 0.0601 and wR = 0.1417 for 908 observed reflections (I > 2s(I)). The Cu(Ⅱ) atom is coordinated by an elongated square pyramid geometry. The deprotonated isonicotinic acid N-oxides form a double-bridge between each pair of Cu(Ⅱ) ions in trans form through two oxygen atoms from the carboxyl groups and two other oxygen atoms from the -NO groups, respectively, which leads to an infinite one dimensional chain. The two adjacent elongated Cu(Ⅱ) square pyramidal geometries are arranged in trans form in the same chain. The OH…O hydrogen bonds extend the chain structure into two-dimensional layers.

Crystal Structure of Borophosphate with 6_1 Screw Axis Helices

A brilliant purple octahedral single crystal is hydrothermally synthesized by the reaction of CoCl26H2O, H3BO3 and H3PO4 in NaOH aqueous solution of CH3(CH2)15N(CH3)3Br, and its crystal structure has been characterized by single-crystal X-ray diffraction. The compound, NaCo(H2O)2BP2O8稨2O (Mr = 336.72), belongs to hexagonal, space group P6122 with a = 9.447(5), c = 15.83(1) , V = 1223(1) 3, Dc = 2.742 g/cm3, Z = 6, F(000) = 1002 and m = 2.606 mm-1. The three-dimensional framework in the compound is built up from the linkage tetrahedral ribbons, in which the BO4 and PO4 tetrahedra alternate with CoO6 octahedra. The sodium ions and water molecules are located within the free thread of the helical ribbons.

几种有机配体配位能力的影响因素研究

在合成单晶的实验过程中我们研究了单晶合成中影响几种羧酸类和含氮的有机配体配位能力的各种 因素,包括pH值、空间因素、温度等,找到了利用该类配体合成单晶的最佳条件．

Controlled synthesis of single-crystal SnSe nanoplates

Two-dimensional layered IV-VI chalcogenides are attracting great interest for applications in next-generation optoelectronic, photovoltaic, and thermoelectric devices. However, great challenges in the controllable synthesis of high-quality IV-VI chalcogenide nanostructures have hindered their in-depth studies and practical applications to date. Here we report, for the first time, a feasible synthesis of single-crystal IV-VI SnSe nanoplates in a controlled manner on mica substrates by vapor transport deposition. The as-grown SnSe nanoplates have approximately square shapes with controllable side lengths varying from I to 6 Dm. Electrical transport and optoelectronic measurements show that as-obtained SnSe nanoplates display p-type conductivity and high photoresponsivity.

Effects of carbon diffusing field in alloy solvent on the growth of tower-shape diamond single crystal

High-quality type-Ib tower-shape diamond single crystals were synthesized in cubic anvil high pressure apparatus (SPD-6×1200) at 5.4 GPa and 1250-1450°C. The (100) face of seed crystal was used as the growth face, and FeNiMnCo alloy was used as the solvent/catalyst. Two kinds of carbon diffusing fields (type-B and type-G) were simulated by finite element method (FEM). Using the two kinds of carbon diffusing fields, many diamond single crystals were synthesized. The effects of carbon diffusing fields on the crystal quality and β value (the ratio of height to diameter of diamond crystal) were studied. The results show that using type-B diffusing field, considerable inclusions appeared in tower-shape diamond crystals with high β values; however, using type- G diffusing field, inclusions were reduced markedly in high β values tower-shape diamond crystals, and the crystal, up to 0.6 carat in weight and 5.3 mm in size, was synthesized. Experimental phenomena were explained well with the help of the FEM.

Synthesis of Monodisperse CexZr1-xO2 Nanocrystals and the Size-Dependent Enhancement of Their Properties

Monodisperse CexZr1-xO2 nanocrystals have been synthesized using a simple two-phase approach; adjusting the ratio of precursors used, amount of capping agent used, reaction time and temperature affords precise control over their composition, structure and size. Size-dependent enhancement of oxygen-storage capacity and kinetics of oxygen storage and release were observed. Systematic studies were conducted in order to understand the size-dependent enhancement of these properties. This work provides important insights into the synthesis and fundamental understanding of multi-component nanocrystals with a large variety of applications.

Syntheses, structures and magnetic properties of three Co(Ⅱ)coordination architectures based on a flexible multidentate carboxylate ligand and different N-donor ligands

Three new cobalt complexes, {[Co5（tci）2（bimb）3（μ3-O）2（H2O）2]·3DMF·4H2O}n（1）, {[Co3（tci）2（bib）]·2DMF·2H2O}n （2） and {[Co（Htci）（bpea）0.5]-H2O}n （3） （H3tci = tris（2-carboxyethyl）isocyanurate, bimb = 4,4＇-bis（imidazol-l-yl）biphenyl, bib = 1,4-bis（imidazol-l-yl）benzene, bpea = 1,2-bis（4-pyridyl）ethane, DMF = N,N＇-dimethylformamide）, have been successfully synthesized through the assembly of Co（If） ions, H3tci and different N-donor ligands, respectively. All complexes were structurally characterized by single crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric （TG） analyses and X-ray powder diffraction （XRPD）. Complex 1 exhibits a 3D three-fold parallel interpenetrated 3D · 3D structure with （65.8） CdSO4 topology. Complex 2 is built from [Co3（μ/2-Ocarboxyl）2（CO2）4] clusters and linear bib ligands, displaying a two-fold par- allel interpenetrated （3,8）-connected （4^3）2（4^6.6^18·8^4） topology, while complex 3 is a 3D pillar-layered structure involving an in- finite -Co-（μ2-Ocarboxyl）（CO2）-Co-chain. The diverse structures of the three complexes indicate that the skeletons of different N-donor ligands play an important role in the assembly of such different frameworks. In addition, magnetic investigation indi- cates that besides spin-orbit coupling of Co（II） ions, there exist antiferromagnetic exchange interactions in Co5 and Co3 clus- ters of 1 and 2, respectively.

Properties of CaB_6 single crystals synthesized under high pressure and temperature

Pure CaB6single crystals are synthesized under high pressure (1 GPa) and temperature (1050°C). The temperature-dependenceof electric resistivity and Hall coefficient from 2 to 300 K shows that the CaB6single crystals are conductors withsemi-metallic behavior and electron carriers. Band structure calculations indicate that the conduction and valence bands meetat the X point at the Fermi level, which is consistent with the experimentally determined conducting behavior of CaB6singlecrystals. Calculations of state density suggest that the states at the Fermi level originate from the 2p orbital of the B atoms andthe 3d orbital of the Ca atom. Magnetization measurements show the paramagnetic nature of the CaB6. The micro-hardness ofCaB6is 24.39 GPa, and the Raman spectra of CaB6yield three sharp peaks at around 780.9, 1138.9, and 1282.1 cm 1for T2g,Eg, and A1g, respectively. The specific heat of the crystal is measured and found to be well described by the Debye and Einsteincombined model. The fitting results show Debye and Einstein temperatures are 1119 and 199 K, respectively.

Synthesis of high quality type-Ib diamond crystals in carats grade

High quality type-Ib tower-shape gem-diamond crystals in carats grade were synthesized in cubic anvil high pressure apparatus (SPD-6×1200) at 5.4 GPa and 1250-1450°C. The relationship between the growth time and the weight of growth diamond has been gained. The faces of {110} and {113} were found in the synthetic diamond crystals frequently. We found that the relative growth rate of {113} face was descending with the increase of growth temperature, and that of {110} face had no obvious change with the increase of the growth temperatures and the growth time. In the work, the crystal defects were studied carefully, and the reasons for the appearance of the defects were also obtained. Some diamond crystals have been polished into the anvil of DAC (Diamond Anvil Cell) and the diamond jewelry. Compared with natural diamond crystal, synthetic diamond crystal has the merits such as small grinding quantity, low cost, etc., so it can be widely used in super high pressure field and gemstone industry.

Effective Approach for the Synthesis of Monodisperse Magnetic Nanocrystals and M-Fe3O4 （M = Ag, Au, Pt, Pd） Heterostructures

Monodisperse and size-tunable magnetic iron oxide nanoparticles （NPs） have been synthesized by thermal decomposition of an iron oleate complex at 310 ℃ in the presence of oleylamine and oleic acid. The diameters of the as-synthesized iron oxide NPs decrease with increasing concentrations of iron oleate complex and oleic acid/oleylamine. In addition, the size-dependent crystallinity and magnetic properties of iron oxide NPs are presented. It is found that larger iron oxide NPs have a higher degree of crystallinity and saturation magnetization. More importantly, various M-iron oxide heterostructures （M = Au, Ag, Pt, Pd） have been successfully fabricated by using the same synthesis procedure. The iron oxide NPs are grown over the pre-made metal seeds through a seed-mediated growth process. The physicochemical properties of Au-Fe3O4 heterostructures have been characterized by X-ray diffraction （XRD）, superconducting quantum interference device （SQUID） magnetometry and UV-vis spectroscopy. The as-synthesized Au-Fe3O4 heterostructures show a red-shift in surface plasmon resonance peak compared with Au NPs and similar magnetic properties to Fe3O4 NPs. The heterojunction effects present in such nanostructures offer the opportunity to tune the irphysicochemical properties. Therefore, this synthesis process can be regarded as an efficient way to fabricate a series of heterostructures for a variety of applications.

Ba4M（CO3）2（BO3）2（M=Ba, Sr）: two borate-carbonates synthesized by open high temperature solution method

Two borate-carbonates Ba4M(CO3)2(BO3)2(M =Ba, Sr) have been successfully synthesized in the open air representing the first examples of borate-carbnate complex.Their structures were determined by single crystal X-ray diffraction and they both crystallize in same space group, Pnma.Their structures feature a Ba/Sr-based three dimensional framework composed of the BaO8 polyhedra(the SrO8 polyhedra), isolated BO3 and CO3 triangles. Detailed structure analysis shows that the intergrowth of [Ba3(BO3)2]/[Ba2Sr(BO3)2] and [BaCO3] layers favors the formation of these two borate-carbonates. In addition, their syntheses, spectroscopic properties and thermal behaviors were investigated.