晶体生长基元与晶体结晶习性

本文从结晶化学角度出发，结合晶体生长实际研究了ＡＯ２、Ａ２Ｏ３和ＡＢＯ３型晶体中ＡＯ６八面体的结晶方位和晶体方位和晶体结晶形貌之间的关系，通过ＢＢＯ、ＬＢＯ高温溶液结构的测定和对水热条件下ＳｉＯ２和ＢＴＯ溶液结构的分析，运用负离子配位多面体生长基元的理论模型解释了晶体的生长形态。     

新型六核钼原子簇化合物｛〔Mo_3（μ_3－S）（μ－S_2）_2（dtp）_3

〔Ｍｏ_３（μ_３－Ｏ）（μ－Ｓ）_３（μ－ＯＡｃ）（ｄｔｐ）_３（ｐｙ）〕和〔Ｍｏ_３（μ_３－Ｓ）（μ－Ｓ）_３（μ－ＯＡｃ）（ｄｔｐ）_３~－（ｐｙ）〕（ｄｔｐ＝Ｓ_２Ｐ（ＯＣ_２Ｈ_５）_２~－）簇合物分别与金属化合物ＢｉＩ_３和ＳｂＢｒ_３进行原子簇反应均能获得意外产物｛〔Ｍｏ_３（μ_３－Ｓ）（μ－Ｓ_２）_２（ｄｔｐ）_３〕（μ_３－Ｓ）（η~３－Ｓ_２）〔Ｍｏ_３（μ_３－Ｓ）（μ－Ｓ）_３（μ－ＯＡｃ）（ｄｔｐ）_２〕｝六核钼簇。其结构实际上是由两个三核钼簇通过一个（μ_３－Ｓ）和一个“把手型”配位方式的（η~３－Ｓ_２）基团连结而成。在晶胞中,通过相邻｛Ｍｏ_６｝簇的Ｓ－Ｓ超分子相互作用组成了沿着ａ轴的｛Ｍｏ_６｝簇链。标题簇合物的结晶学参数如下：三斜晶系,空间群,ａ＝１３．７２６（４）,ｂ＝１４．８９９（４）,ｃ＝１７．６１０（５）,α＝１０７．４３（２）°,β＝８１．６３（３）°,γ＝１０３．３６（２）°,Ｖ＝３３３２（４）,Ｚ＝２．对５７７１个Ｉ＞３σ（Ｉ）的衍射点,最终结构偏离因子Ｒ＝０．０５６,Ｒ_ω＝０．０６１。     

Synthesis and Crystal Structure of （Et4N）3[{V（o—C6H4OS）3}2Na]

ＳｙｎｔｈｅｓｉｓａｎｄＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆ（Ｅｔ_４Ｎ）_３［｛Ｖ（ｏ－Ｃ_６Ｈ_４ＯＳ）_３｝_２Ｎａ］￥ＷｅｎＴｉｎｇ－Ｂｉｎ；ＸｕＹｏｎｇ－Ｊｉｎ；ＳｈｉＪｉ－Ｃｈｅｎｇ；ＤｅｎｇＹｕ－Ｈｅｎｇ；ＣｈｅｎＣｈａｎｇ－Ｎｅｎｇ；Ｌｉｕ...     

Crystal Structure of Tris－（dimethoxyphosphato） Lanthanum（Ⅲ） Coordination Polymer｛La〔PO_2（OCH_3）_2〕_3｝_n

ＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆＴｒｉｓ－（ｄｉｍｅｔｈｏｘｙｐｈｏｓｐｈａｔｏ）Ｌａｎｔｈａｎｕｍ（Ⅲ）ＣｏｏｒｄｉｎａｔｉｏｎＰｏｌｙｍｅｒ｛Ｌａ〔ＰＯ_２（ＯＣＨ_３）_２〕_３｝_ｎ￥ＺｅｎｇＧｕａｎｇ－Ｆｕ；ＧｕｏＸｉｎ；ＷａｎｇＣｕｉ－Ｙ?..     

Syntheses， Structuresand Reactivity of Incomplete Cubane－like Compound［｛W_3S_4｝｛S_2P（OEt）_2｝_4（H_2O）］and Its Derivates

Ｓｙｎｔｈｅｓｅｓ,ＳｔｒｕｃｔｕｒｅｓａｎｄＲｅａｃｔｉｖｉｔｙｏｆＩｎｃｏｍｐｌｅｔｅＣｕｂａｎｅ－ｌｉｋｅＣｏｍｐｏｕｎｄ［｛Ｗ_３Ｓ_４｝｛Ｓ_２Ｐ（ＯＥｔ）_２｝_４（Ｈ_２Ｏ）］ａｎｄＩｔｓＤｅｒｉｖａｔｅｓ￥ＷｕＸｉｎ－Ｔａｏ;ＷａｎｇＱｕａ...     

二［氧合—二（4—二茂铁基苯甲酸二烷基锡（Ⅳ））］配合物？…

合成了｛［（ｎ－Ｂｕ）２Ｓｎ（４－Ｆｃ－Ｃ６Ｈ４ＣＯＯ）］２Ｏ｝２（１）和｛［ｎ－Ｏｃｔ）２Ｓｎ（４－Ｆｃ－Ｃ６Ｈ４ＣＯＯ）］２Ｏ｝２（２）（Ｆｃ＝ｆｅｒｒｏｅｎｙｌ两组新的配合物,对其进行了元素分析,并用ＩＲ,ＮＭＲ（＾１Ｈ,＾１３Ｃ,＾１１９Ｓｎ）进行了谱学表征,单晶Ｘ射线衍射法测定表明,配合物１的晶体属单斜晶系,Ｐ２１／ｃ空间群,晶胞参数ａ＝１．２９８８（１）ｎｍ,ｂ＝２．６５５（１）ｎｍ,     

紫外非线性光学材料硼酸盐晶体生长的研究进展

主要论述了近十多年来由我所发现和发展起来的几种重要的紫外非线性光学材料如ＢＢＯ、ＬＢＯ和ＫＢＢＦ等的晶体生长方面的研究工作进展。其中包括：晶体生长方法的选择和晶体生长技术与发展；助溶剂的选择；溶结构及其他生长条件对晶体生长的影响；ＢＢＯ晶体亚稳相生长和从纯熔体中直接提拉生长β相ＢＢＯ晶体；晶体的生长习性、缺陷以及晶体生长的其他一些重要问题。     

Crystal and Molecular Structures of［Cu_2（OAc）_4（Ur）_2］．2H_2O and｛［Cu（H_2Y）］．Ur·H_2O｝_n（Ur＝urea； H_4Y＝EDTA）

ＣｒｙｓｔａｌａｎｄＭｏｌｅｃｕｌａｒＳｔｒｕｃｔｕｒｅｓｏｆ［Ｃｕ_２（ＯＡｃ）_４（Ｕｒ）_２］．２Ｈ_２Ｏａｎｄ｛［Ｃｕ（Ｈ_２Ｙ）］．Ｕｒ·Ｈ_２Ｏ｝_ｎ（Ｕｒ＝ｕｒｅａ；Ｈ_４Ｙ＝ＥＤＴＡ）￥ＺｈａｎｇＨａｎ－Ｈｕｉ；ＹｅＺｈａｏ；ＹａｎｇＲｏｎｇ...     

BIS-PER(POLY)FLUOROALKYLATION OF PARA-SUBSTITUTED PHENOLS BY R_FI/Na_2S_2O_4 REAGENT SYSTEM

ＢＩＳ－ＰＥＲ（ＰＯＬＹ）ＦＬＵＯＲＯＡＬＫＹＬＡＴＩＯＮＯＦＰＡＲＡ－ＳＵＢＳＴＩＴＵＴＥＤＰＨＥＮＯＬＳＢＹＲ_ＦＩ／Ｎａ_２Ｓ_２Ｏ_４ＲＥＡＧＥＮＴＳＹＳＴＥＭ￥ＷｅｉＹｕａｎＨｕａｎｇ；ＨｏｎｇＢｉｎＹｕ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆ...     

2-甲酯基丙基合锡(Ⅳ)配合物的固相合成

利用２－甲酯基丙基三氯化锡与六甲基磷酰三胺（Ｌ＾１）、苯甲醛缩邻氨基苯酚（ＨＬ＾２）及２－甲基－８－羟基喹啉（ＨＬ＾３）的低热固相反应合成了六个新的含２－甲酯基丙基的锡（Ⅳ）配合物ｎＣｌ３｛ＣＨ２ＣＨ（ＣＨ３）ＣＯ２ＣＨ３｝Ｌ＾１ｎ」（ｎ＝１,２）和「ＳｎＣｌ３－ｎ｛ＣＨ２ＣＨ（ＣＨ３）ＣＯ２ＣＨ３｝（民,２：Ｌ＝Ｌ＾２,Ｌ＾３）,通过元素分析、红外光谱、核磁共振对其进行了表征。用Ｘ－射线单晶衍射     

Nucleation-controlled growth in polyethylene single crystals: Growth and shape of {100} sectors

The nucleation rate and propagation rate of steps on the {100} faces of polyethylene crystals have been determined. For single crystals, under conditions where the width of the {100} sectors remains constant during growth, it is confirmed that the growth is in regime I or the crossover region between regime I and II. In {110} twinned crystals, the {100} sectors are well developed and the width increases linearly with time; therefore, the growth in the twins must be in regime II. It is shown that the differing growth regimes of {100} faces in single crystals and twins allow the independent determination of the nucleation rate and the propagation rate of steps. The nucleation rate and propagation rate of steps on the {100} faces were determined from measurements of the constant width of the {100} faces in single crystals and the growth rate of the {100} faces in single crystals and twins. The observed rates show abnormal dependence on supercooling and concentration. The results are attributed to a weaker dependence of the constant width of {100} sectors on supercooling and concentration than predicted.     

Mimicking the biomolecular control of calcium oxalate monohydrate crystal growth: effect of contiguous glutamic acids

Scanning confocal interference microscopy (SCIM) and molecular dynamics (MD) simulations were used to investigate the adsorption of the synthetic polypeptide poly(l-glutamic acid) (poly-glu) to calcium oxalate monohydrate (COM) crystals and its effect on COM formation. At low concentrations (1 μg/mL), poly-glu inhibits growth most effectively in ?001? directions, indicating strong interactions of the polypeptide with {121} crystal faces. Growth in ?010? directions was inhibited only marginally by 1 μg/mL poly-glu, while growth in ?100? directions did not appear to be affected. This suggests that, at low concentrations, poly-glu inhibits lattice-ion addition to the faces of COM in the order {121} > {010} ≥ {100}. At high concentrations (6 μg/mL), poly-glu resulted in the formation of dumbbell-shaped crystals featuring concave troughs on the {100} faces. The effects on crystal growth indicate that, at high concentrations, poly-glu interacts with the faces of COM in the order {100} > {121} > {010}. This mirrors MD simulations, which predicted that poly-glu will adsorb to a {100} terrace plane (most calcium-rich) in preference to a {121} (oblique) riser plane but will adsorb to {121} riser plane in preference to an {010} terrace plane (least calcium-rich). The effects of different poly-glu concentration on COM growth (1-6 μg/mL) may be due to variations between the faces in terms of growth mechanism and/or (nano)roughness, which can affect surface energy. In addition, 1 μg/mL might not be adequate to reach the critical concentration for poly-glu to significantly pin step movement on {100} and {010} faces. Understanding the mechanisms involved in these processes is essential for the development of agents to reduce recurrence of kidney stone disease.     

An electron microscope study of some nonstoichiometric tungsten oxides

Large crystals of WO₃ have been reduced to a composition of approximately WO_2.91 at 3 different temperatures, 950, 1000, and 1070°C. After reduction the crystals were examined by optical microscopy and transmission electron microscopy. The crystals were faulted in a variety of ways and rarely perfectly ordered. Large crystals heated at 1070°C supported oxygen loss by formation of {103} CS planes while crystals heated at 950°C contained {102} CS planes. At 1000°C {102} and {103} CS planes coexisted. It was found that the way in which the WO₃ structure accommodated oxygen loss was a function of composition and of temperature. In all experiments, some vapour transport also took place, resulting in the growth of needle shaped crystals. These were always members of the W_xO_3n?2 homologous series of oxides, and contained {103} CS planes, irrespective of the formation temperature.     

铅基复合钙钛矿型弛豫铁电单晶的生长基元与生长机理Ⅰ.PMNT单晶的表面形貌、负晶结构及生长基元的组装与拆分

铅基复合钙钛矿型弛豫铁电单晶体PMNT的生长基元为多种[BO_6]配位八面体,晶体生长过程可视为多种八面体基元与Pb~(2 )的组装过程.这些生长基元向{111}面叠合时易采取法向生长机制,向{001}面叠合时易采取层状生长机制,由此决定了晶体生长速度的各向异性与晶体的形貌.Bridgman法生长的PMNT晶体在生长过程中由内向生长机制形成规则的负晶结构;在晶体生长过程中,在其自然表面上可形成正形与负形两种形貌;在高温退火过程中,由于PbO的分解,晶体表面上可形成类似“蚀象”的构型,这些可从[BO_6]八面体生长基元的组装或拆分方面获得解释.     

Carrier Recombination of Organic-Inorganic 3D Halide Perovskite Single Crystals

Organic-inorganic 3D halide perovskite materials recently have become one of the major players of hybrid semiconductors for photovoltaic and optoelectronic applications. The diffusion length of charge carriers is one of the critical parameters for justifying photovoltaic applications of materials. In this work, we propose a realistic kinetic model in order to fully understand carrier relaxation rate of photoexcited organic perovskites with a negligible exciton formation in photoluminescence lifetime measurements. We find that the extraction of carrier relaxation rate has to be made from multiple fluence-dependent photoluminescence lifetime measurements with global fittings, instead of a traditional single-fluence lifetime measurement. To demonstrate the validity of the model, two kinds of p-doped CH\begin{document}$ _3 $\end{document}NH\begin{document}$ _3 $\end{document}PbI\begin{document}$ _3 $\end{document} single crystals were grown up by intentionally increasing defects. Global fittings of the kinetic model to the two kinds of single crystals yield doping density, trap density, and recombination constants. Our methodology provides a self-contained approach to determine diffusion lengths of organic 3D halide perovskite materials.     

Growth of polyethylene single crystals from the melt: change in lateral habit and regime I–II transition

Using the technique of extraction, single crystals have been obtained from polyethylene fractions isothermally crystallized from the melt at atmospheric pressure. It has been found that the lateral habit of single crystals changes in the vicinity of the transition temperature of growth regime (regime I–II): lenticular shape elongated in the direction of theb axis (type A) in the range of regime I and truncated lozenge with curved edges of {200} and {110} growth faces (type B) in that of regime II. The transition of lateral habit causes a drastic change in the width of {110} growth faces; {110} growth faces are well developed in type B crystals while they cannot be observed and must be very small in type-A crystals. It has been shown that the growth regime of the small {110} growth face of type-A crystals must be in regime I; hence the regime I–II transition can be explained as the result of this change in lateral habit (width of the {110} growth face).     

Effect of sunset yellow dye on morphological,optical, dielectric,thermal and mechanical properties of KDP crystal

Herein, we describe the growth and morphology of well-defined dyed crystals of KH₂PO₄ (potassium dihydrogen orthophosphate; KDP) containing organic azo (sunset yellow; SSY) dye in the {1 0 1} & {0 0 1} pyramidal growth sectors. An understanding on selective dye inclusion in various growth sector of host crystal is proposed, which will help in designing novel tailor-made dyed photonic crystals. The structural analysis and the identification of various functional groups present in as grown KDP crystals were carried out using powder XRD, FTIR and Raman studies. Solid state transmittance spectra for dyed KDP crystals displayed three absorption peaks at 230 nm, 311 nm and 477 nm, which were blue shifted for SSY dye in KDP crystal relative to neutral aqueous solution of SSY dye. These blue shifts in the absorption maxima confirm the successful incorporation of sunset yellow dye into the pyramidal growth sectors of dyed KDP crystals. The band around 409 nm in the photoluminescence emission spectrum indicates a violet emission. SSY dye doped KDP crystals showed enhanced dielectric properties and thermal stability as compared to pure KDP crystal. The mechanical strength of the KDP crystals estimated using Vickers microhardness test was found to decrease with the increase in SSY dye doping.     

Synthesis and structure of the framework coordination polymer based on the cluster anion [Nb<Subscript>4</Subscript>OTe<Subscript>4</Subscript>(CN)<Subscript>12</Subscript>]<Superscript>6−</Superscript> and Mn<Superscript>II</Superscript> aqua complexes

Dark-brown plate crystals of the [Mn₇(H₂O)₂₆{Nb₄OTe₄(CN)₁₂} ₂](OH)₂·11H₂O compound (1) were prepared by the reaction of an aqueous ammonia solution of the K₆[Nb₄OTe₄(CN)₁₂]{K₂CO₃{KOH{8H₂O complex with a glycerol solution of manganese(II) nitrate. The structure of complex 1 was established by X-ray diffraction. Compound 1 has a polymer structure containing four types of manganese atoms. The nitrogen atoms of eight cyano groups of the tetranuclear niobium cluster are coordinated to the manganese atoms to form a {2,3,8}-connected three-dimensional network. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 224–228, February, 2007.     

A new equilibrium form of zircon crystal

The surface tensions of the {100}, {110}, {101} and {211} faces are calculated by using Machenzie's method. A new equilibrium form of zircon crystal is then derived on the basis of Wulf's Law. This theoretic form consists of {100} prismatic faces and {211} pyramidal faces, which is different from that of the prediction by the periodic bond chain theory. The discovery of the equilibrium form of zircon crystal provides a clue for understanding of the morphology of zircon crystals formed in deep magma chamber, indicating that zircon morphology is an indicator of crystallization conditions.     

Direct Observation of Transition Metal Dichalcogenides in Liquid with Scanning Tunneling Microscopy

We present atomic-resolution images of TiSe\begin{document}$_2$\end{document}, MoTe\begin{document}$_2$\end{document} and TaS\begin{document}$_2$\end{document} single crystals in liquid condition using our home-built scanning tunneling microscopy (STM). By facilely cleaving of single crystals in liquid, we were able to keep the fresh surface not oxidized within a few hours. Using the high-stable home-built STM, we have obtained atomic resolution images of TiSe\begin{document}$_2$\end{document} accompanied with the single atom defects as well as the triangle defects in solution for the first time. Besides, the superstructure of MoTe\begin{document}$_2$\end{document} and hexagonal charge-density wave domain structure in nearly commensurate phase of TaS\begin{document}$_2$\end{document} were also obtained at room temperature (295 K). Our results provide a more efficient method in investigating the lively surface of transition metal dichalcogenides. Besides, the high stable liquid-phase STM will support the further investigations in liquid-phase catalysis or electrochemistry.