基于1,2,4-三唑与水桥联的双核镉配合物的合成、晶体结构及荧光性质

利用缓慢蒸发溶剂法合成了双核镉配合物[Cd2(dpatrz)2Br4(H2O)](dpatrz=3,5-丙基-4-氨基-1,2,4-三唑).通过元素分析、红外光谱和粉末衍射进行了常规表征,同步辐射光源衍射结构分析给出该配合物结晶于四方晶系空间群P42/n.Cdl中心为五配位[CdN2OBr,],呈扭曲的三角双锥几何构型,中心对称的两个Cd原子通过两个μ1.2-dpatrz和一个H2O分子桥连形成双核结构,氢键作用加强了空间结构的稳定性并形成一维链结构.对配合物的热重分析与室温下固体荧光也分别进行了研究.     

乙二胺四乙酸铋(Ⅲ)双核配合物的合成和晶体结构

以乙二胺四乙酸(H4edta)的配合物[Sb(Hedta)]·H2O和硝酸铋为主要原料,在水溶液中合成了双核的二维网状配合物[Bi2 (Hedta)2]·4H2O,用元素分析、X射线单晶衍射法、红外光谱以及热分析等方法进行了组成和结构表征.结果表明该配合物属于单斜晶系,空间群Cc,晶胞参数为a=1.720419(15) nm,b=0.68549 (5) nm,c=1.32906(11) nm,β=105.7590 (10)°,V=1.5085 (2) nm3,Z=2,Dc=2.352 g·cm-3,μ=11.744 mm-1,F(000)=1016,R1=0.0556,wR2 =0.1393.在该配合物中,Bi (Ⅲ)与同一个Hedta3-配体中的4个羧基O原子和2个氨基N原子以及来自两个不同Hedta3-配体的桥联羧基氧原子结合,形成了配位数为8的双帽三棱柱构型.配合物的热分解过程包括失水、配体的氧化分解,最后在450℃失重恒定并形成Bi2O3.     

奥沙拉秦钙配合物的合成、结构及表征

本文通过CaCl2·2H2O与药物奥沙拉秦及辅助配体邻菲罗啉在水热条件下得到了一个新的奥沙拉秦配合物[ Ca(L) (Phen)·4(H2O)]n(H2L=奥沙拉秦=3,3-azo-bis-6-hydroxybenzoic acid)(1).通过元素分析、红外对配合物进行了表征,并利用X单晶射线衍射仪测定了其结构.结构解析表明,配合物1属三斜晶系,空间群P-1,晶胞参数a=0.8001 (3) nm,b=1.1245(4) nm,c=1.5129(6) nm,α=89.450(6)°,β=86.297(6)°,γ=77.633(6)°,V=1.3268(9) nm3,Z=2,F(000) =636,最终偏差因子(对Ⅰ＞2σ(Ⅰ)的衍射点),R1=0.0521,wR2 =0.1538,S=1.045.在该结构中,中心Ca(Ⅱ)离子周围形成了一个稍微扭曲的五角双锥体,分别与一个来自奥沙拉秦配体的羧基氧原子(单齿)、两个邻菲罗啉中的两个N原子和四个水分子配位.     

链状钴配合物的水热合成、晶体结构及荧光性质

采用水热法合成得到了链状钴配合物[Co(4,4'-bipy)(H2O)4]n· 2nH2L· 4nH2O(H2L-＝2,5-二羟基苯磺酸离子,4,4'-bipy＝4,4'-联吡啶).采用X射线单晶衍射、元素分析、红外光谱、热重分析等对配合物进行了组成和结构表征.单晶衍射研究表明,配合物中钴离子与4,4'-bipy的氮原子配位和水分子的氧原子配位,形成扭曲的八面体配位构型. H2L-配体没有配位,只是平衡结构中的电荷.在结构单元中,[Co(4,4'-bipy)(H2O)4] +,H2L-和H2 O之间通过氢键相连.配合物的荧光发射峰与配体相比发生了红移,最大发射峰在411 nm.     

2,6-二甲基苯基-β-二亚胺配合物的合成及表征

通过液相扩散法得到了2,6-二甲基苯基-β-二亚胺的铜、镍配合物,配合物的结构通过红外光谱,X-粉末衍射及元素分析表征,X射线单晶衍射进一步确定配合物的结构.单晶结构显示,配合物为三斜晶系,空间群P1,分子式为C44 H54 MN4 O4(M:Cu,Ni),空气中的O原子,甲醇分子的CH3 O-插入到β-二亚胺的亚甲基上,导致了两分子配体的两个N原子,插入的O原子与金属中心配位,生成了双配体四齿单金属配合物,形成了新颖的配位模式.在铜、镍配合物中,面与面之间依靠C-H?π键弱的相互作用力构建成二维层状结构.     

两个单核配合物晶态荧光材料的合成、晶体结构及性质

在水中采用蒸发溶剂的方法,合成了两个晶态单核配合物[Co(phen)3]·2H2SPA·0.5HSPA·10H2O(1)和[Ni(phen)2(H2O)2]·H2SPA·0.5HSPA·3H2O(2)(H2SPA'=间苯二甲酸-5-磺酸根阴离子,phen=1,10-邻菲罗啉).在配合物1中,中心离子与三个1,10-邻菲罗啉配位,形成[Co(phen)3]2+.未配位的水分子与阴离子H2SPA-和HSPA2-通过氢键相互连接形成三维的网状结构.在配合物2中,中心离子与两个1,10-邻菲罗啉分子和两个水分子配位,构成阳离子[Ni (phen)2(H2O)2]2+.阳离子[Ni (phen)2(H2O)2]2+与自由的阴离子H2SPA-、阴离子HSPA-和未配位的水分子通过氢键连接形成三维网状结构.室温下两个配合物均具有荧光发射峰,其发射峰分别在460 nm和439 nm.与配体相比,均发生明显的红移.荧光寿命分别为1.1244 ns和1.4882 ns.     

二聚体配合物[Mn(1,6-nds)(phen)_2(H_2O)]_2·(CH_3OH)_3·(H_2O)_2的合成、晶体结构及荧光性质

采用水热法合成了二聚体Mn(Ⅱ)配合物[Mn(1,6-nds)(phen)2(H2O)]2·(CH3OH)3·(H2O)2,(1,6-nds=1,6-萘二磺酸根离子,phen=1,10-邻菲罗啉)。采用X射线单晶衍射、红外光谱、热重分析和紫外可见光谱等方法对配合物进行了表征。X射线单晶衍射表征结果表明,该配合物晶体属于三斜晶系,空间群为P-1。锰离子与两个1,10-邻菲罗啉分子、一个水分子和1,6-萘二磺酸根离子配位,形成[Mn(1,6-nds)(phen)2(H2O)]结构单元。这种结构单元、未配位的甲醇和水分子通过两种类型的氢键O-H…O和O-H…S相连,形成三维网状结构。与配体相比,配合物的荧光光谱发生红移,其最大发射峰在439 nm。     

之字链配合物Cu(phth)2(H2O)2的合成、表征及晶体结构

用Cu(NO3)2·3H2O和phth(邻苯二甲酸)混合反应得到了配合物Cu(phth)2(H2O)2(1).通过元素分析、红外光谱对配合物进行了表征,用X射线单晶衍射仪测定了配合物的晶体结构.配合物为单斜晶系,P2(1)/c空间群.晶胞参数a=0.83895(17)nm,b=1.4441(3)nm,c=0.70992(14)nm,β=112.14(3)°,V=0.7967(3)nm3,Z=2,Dc=1.792 g/cm3,F(000)=438.0,S=1.100,R1=0.0376,wR2=0.0998.铜原子为四配位,呈畸变正方形构型,通过邻苯二甲酸根的π-π堆积作用形成了一维之字型链,相邻的链之间靠氢键和π-π堆积作用形成三维分子结构.     

以1,2,5-噻二唑-3,4-二酸为配体的碱土金属配合物的合成、晶体结构及配位模式

以1,2,5-噻二唑-3,4-二酸为单一配体与第二主族碱土金属离子通过水热法合成了三个配合物,对其进行了元素分析及单晶衍射结构解析,并对H2tdzdc配体的配位能力、配位模式等特性作了初步研究.结果表明:单核配合物1,[Mg(tdzdc)(H2O)4]属于三斜晶系,空间群为P1;配位聚合物2,[Ca(tdzdc)(H2O)2]n,具有二维层状结构,属于单斜晶系,空间群为C2/c;配位聚合物3,[Sr(tdzdc)(H2O)3]n,具有二维层状结构,属于三斜晶系,空间群为P1.通过研究发现,当使用ⅡB主族的碱土金属与1,2,5-噻二唑-3,4-二酸根进行配位时,随着金属离子半径的增加和电子层数的增多,金属离子的配位数增多,得到的Mg、Ca、Sr的配合物结构愈加复杂,即从单核配合物到配位聚合物.     

两个晶态异质同构配合物荧光材料的合成、结构及性质

在水中采用蒸发溶剂的方法,合成了两个异质同构的单核配合物[M(phen)2(H2O)2]·2SIPH2·2H2O (M=Zn,Co),SIPH2=间苯二甲酸-5-磺酸根阴离子,phen=1,10-邻菲罗啉).在两个配合物结构单元中,中心离子与两个1,10-邻菲罗啉和两个水分子配位,形成[M(phen)2(H2O)2]2+阳离子.两个未配位的水分子与[M(phen)2(H2O)2]2+阳离子,SIPH2-阴离子通过氢键相互连接形成三维的网状结构.SIPH2-阴离子起到平衡电荷的作用.室温下两个配合物均具有荧光发射峰,其发射峰分别在460 nm和439 nm.与配体相比,均发生明显的红移.荧光寿命分别为1.7638 ms和1.6356 ms.     

Glass foams: formation, transport properties, and heat, mass, and radiation transfer

Energy efficiency, environmental impact, and quality of the final product in glass manufacturing depend, to a large extent, on foams formed on the surface of the molten glass and of the batch due to entrapment of gas bubbles generated by the batch fusion and refining chemical reactions during the melting process. Hence, understanding the mechanisms of foam formation as well as development of theoretical models for thermophysical and transport properties and heat, mass, and radiation transfer in glass foams are not only a problem of significant fundamental interest but also of tremendous practical impact. In this paper, the review of the current state-of-the-art in our understanding of glass foams is provided, including some of our recent results in modeling the dynamics of the foam growth and its steady-state thickness, prediction of gas diffusion through glass foams, and thermal radiative properties of glass foams. In addition, the new results on simulation of combined conduction and radiation heat transfer in glass foams and radiative transfer in primary (batch) foams are presented and discussed in some detail. The paper also presents practical means available for reducing foaming in glass melting and concludes with the discussion of unresolved problems and summary of the directions for the future work in the area.     

Apparent entropy,residual entropy,causality, metastability,constraints, and the glass transition

A thermodynamic framework for the investigation of ‘residual entropy’ and related phenomena is developed, expanding and clarifying the work of Kivelson and Reiss and the important work of several other investigators. The main difficulties encountered in the development of such a framework are the need to deal with constrained equilibrium as well as to include irreversible processes in the overall study. These challenges are met by using the device of auxiliary constraints and the equivalent equilibrated states that they produce. The importance of a thermodynamic framework is tied to the fact that evolving molecular theories of residual entropy, which also impact the glass transition, no matter how sophisticated, invariably contain approximations whose effects are hard to assess. Thus a thermodynamic framework provides a vehicle within which the internal consistency of a theory can be tested. Phenomena that are treated in such a framework, along with others, are those mentioned in the title of this paper. The concept of residual entropy, its reality or unreality, is often considered to be an unimportant issue. The findings of this paper, besides emphasizing the unreality of residual entropy, show that the question of its existence is a significant one. Among other things, the fundamental principle of causality is involved and we should not be so cavalier as to dispense with it. Among other rigorous analysis we present an argument involving an ideal binary solution whose behavior as the limiting behavior of a real solution provides access, in principle, to experiment. The argument does make the generally accepted assumption that, at equilibrium at 0 K, pure crystals of the binary system’s components have zero entropy. It strongly suggests that residual entropy, in general, is an impression that stems from the inclusion of an irreversible step in an experimental thermodynamic cycle.     

Methods,Syntheses and Characterization of Diaryl,Aryl Benzyl,and Dibenzyl Sulfides

Twenty-four aryl benzyl sulfides, diaryl sulfides and dibenzyl sulfides were synthesized by four methods and characterized by ¹H NMR, FT-IR and Gas chromatography. The reaction conditions of different synthesis methods were studied from the aspects of time, solvent, base and dispersant. The molecular structures of benzylphenyl sulfide (2S), (4-tert-butylbenzyl)(4-methylphenyl) sulfide (4S), (4-methylbenzyl)(4-methylphenyl) sulfide (9S), di(4-methylphenyl) sulfide (11S), (3,5-dimethylphenyl)(4-methyl phenyl) sulfide (15S), and dibenzyl sulfide (19S) [22] have been determined by single-crystal X-ray crystallography. Compounds 2S and 15S crystallize in the monoclinic space group P2₁/c, with a?=?12.278(3), b?=?15.894(3), c?=?5.6056(11) Å, β?=?94.532(2)°, and Z?=?4 for 2S, and a?=?9.800(9), b?=?7.950(7), c?=?16.690(15) Å, β?=?100.890(12)°, and Z?=?4 for 15S. The unit cell of 4S has a triclinic Pī symmetry with the cell parameters a?=?6.0436(10), b?=?8.7871(14), c?=?15.535(2) Å, α?=?81.921(2)°, β?=?81.977(2)°, γ?=?80.889(2)°, and Z?=?2. Compounds 9S and 11S both crystallize in the orthorhombic space group P2₁2₁2₁, with a?=?6.188(3), b?=?8.041(4), c?=?26.005(14) Å, and Z?=?4 for 9S, and a?=?5.835(2), b?=?8.010(3), c?=?25.131(9) Å, and Z?=?4 for 11S.

Graphic Abstract

Twenty-four aryl sulfide compounds with different substituents were synthesized and characterized, and the molecular structures of six different sulfide compounds have been determined by single-crystal X-ray crystallography.

     

Synthesis and Structure Determination of 1, 4, 7, 11, 14, 17, 21, 24, 27-Nonaoxatriacontan-8, 10, 18, 20, 28, 30-Esaone

The title compound crystallizes in the trigonal space group R-3, with unit-cell parameters: a = 23.261(4), c = 9.537(2) Å; λ(MoKα) = 0.71073 Å, V = 4469(2) Å³, and Z = 6. The structure has been solved by direct methods using X-ray diffraction techniques. The final reliability index for the computed structure is 0.0826 for 929 observed reflections and 121 refined parameters. Crown ether adopts an almost circular shape and macrocycles are piled up in a columnar arrangement forming tubular nanochannels. The channels are filled with guest CDCl₃ molecules, characterised by rotational disorder.     

Intermetallic Compounds CsnMk (М = Na,K, Rb,Pt, Au,Hg, Te): Geometrical and Topological Analysis,Cluster Precursors,and Self-Assembly of Crystal Structures

Crystallography Reports - A geometrical and topological analysis has been performed, and self-assembly of the crystal structures of intermetallic compounds CsnMk (М = Na, K, Rb, Pt, Au, Hg,...     

D-β,β-dimethylcysteic acid,its preparation,structure, and spectroscopic properties

The X-ray crystal structure ofd-,-dimethylcysteic acid, C₅H₁₁NO₅S, has been determined. The compound is monoclinic, space groupP2₁₄ (No. 4), with cell dimensionsa=8.133(1),b=8.094(1),c=6.3138(7) Å,=96.36(1)° andZ=2. The structure was solved by Patterson and electron density difference methods and refined toR=0.025,R _w=0.022 for 1081 reflections. Bond lengths and angles do not differ from those in similar structures. The crystal is held together by intermolecular hydrogen bonds. The vibrational spectra have been recorded and assigned and the¹ H and¹³C NMR spectra were measured.     

Single Crystal Growth and Pyroelectric,Dielectric, Piezoelectric,Elastic, and Thermoelastic Properties of Orthorhombic Li2SiO3, Li2GeO3, and Na2GeO3

Single crystals of optical quality of isotypic Li₂SiO₃, Li₂GeO₃, and Na₂GeO₃, space group Ccm2₁, with diameters of ca 16 mm and lengths of ca 20 mm (Li₂SiO₃) and ca 60 mm (Li₂GeO₃ and Na₂GeO₃) have been grown from the melt using the Czochralski technique. On Li₂SiO₃, Li₂GeO₃, and Na₂GeO₃ pyroelectric coefficients and complete dielectric, piezoelectric, elastic, and thermoelastic tensor properties have been determined; the latter from the temperature dependence of resonance frequencies. All crystals investigated exhibited only a small amount of 180° twins. They all possess large pyroelectric coefficients about-five times that of tourmaline. The longitudinal piezoelectric constant d₃₃₃ is about five times larger than d₁₁₁ of alpha quartz. Qualitative measurements on Na₂SiO₃ revealed similar values of pyroelectric and piezoelectric effects. The technical application of these crystals encounters some difficulties: Li₂SiO₃ is excellently cleavable parallel (010). This face contains the polar direction [001]. Na₂GeO₃ suffers from chemical decomposition in humid atmosphere and is well cleavable too. Both happens to a much less extent in Li₂GeO₃. Na₂SiO₃ proved to be hardly suitable for any application of its polar properties due to its bad chemical stability against humid air and its excellent cleavage.     

Electrons,dislocations, and low-temperature plastic deformation

The influence of electron drag processes on the plasticity of normal state metals is demonstrated in the case of zinc crystals. These results show that dislocations move as underdamped oscillators at low temperature and that dislocations flutters as they move. This flutter motion, in contrast to kink motion which is expected to have no long range stress, is the dominant drag process at temperatures below ≈ 4.2 K.     

Quasipollucites and their mixed frameworks,block isomorphism,and superstructures

The structure type of analcime (ANA) is interpreted based on the basic block: a six-membered ring of tetrahedra which is generated by two template cations. The uncertainties in the composition and/or structure of alumophosphate, ferrisilicate, and titanosilicate pollucites, which are complicated by adding H₂O molecules and (OH)⁻ or O²⁻ anions, are eliminated. The block isomorphism and formation of super-structures in these pollucites is discussed. In view of the transformation of tetrahedral ANA frameworks into mixed ones, we propose that they be considered analcimoidal (quasipollucites).