Synthesis,Crystal Structures,Thermal and Magnetic Properties of New Selenocyanato Coordination Polymers with Pyrazine as Co‐Ligand

Reaction of iron(II), cobalt(II) and nickel(II) selenocyanate with pyrazine in water at room temperature leads to the formation of the isotypic new ligand‐rich 1:2 (1:2 = ratio between metal and co‐ligand) compounds [M(NCSe)₂(pyrazine)₂]_n (M = Fe ( 1 ), Co ( 2 ), Ni ( 3 )). The crystal structure of 2 was determined by X‐ray single crystal analysis and those of 1 and 3 were refined from X‐ray powder data with the Rietveld method. In their crystal structure the metal(II) cations are coordinated by four pyrazine co‐ligands, which connect them into layers, and two terminally N‐bonded selenocyanato anions in a distorted octahedral arrangement. The terminal coordination mode of the selenocyanato anions was further emphasized by IR spectroscopic investigations. On heating, all compounds decompose in a single heating step without the formation of ligand‐deficient intermediates like previously reported for related thiocyanato compounds. Magnetic measurements of compound 1 show a long‐range antiferromagnetic ordering with an ordering temperature of T_N = 6.7 K, which must be mediated by the aromatic π‐system of the pyrazine ligand, whereas 2 and 3 show only Curie–Weiss behavior with antiferromagnetic exchange interactions.     

Synthesis,Structures, and Properties of Branched Oligogermanes

Abstract

We have employed the hydrogermolysis reaction for the preparation of rare branched oligogermanes, and have obtained for the first time the X-ray crystal structures of several branched tetragermanes, including (Ph₃Ge)₃GePh, (Ph₃Ge)₃GeH, and (Ph₃Ge)₃GeX (X = Cl or Br). We also have at our disposal branched tetragermanes having the formula (EtOCH₂CH₂Bu ⁿ ₂Ge)₃GePh, where the ethoxyethyl substituent serves as a protecting group for a germanium–hydride active site. These reagents have been employed for the stepwise synthesis of higher branched systems having up to 13 bonded germanium atoms in the oligomer backbone. The synthesis, structures, and physical characteristics of these systems are described.

GRAPHICAL ABSTRACT     

Syntheses and Structures of Xenon Trioxide Alkylnitrile Adducts

The potent oxidizer and highly shock‐sensitive binary noble‐gas oxide XeO₃ interacts with CH₃CN and CH₃CH₂CN to form O₃XeNCCH₃, O₃Xe(NCCH₃)₂, O₃XeNCCH₂CH₃, and O₃Xe(NCCH₂CH₃)₂. Their low‐temperature single‐crystal X‐ray structures show that the xenon atoms are consistently coordinated to three donor atoms, which results in pseudo‐octahedral environments around the xenon atoms. The adduct series provides the first examples of a neutral xenon oxide bound to nitrogen bases. Raman frequency shifts and Xe?N bond lengths are consistent with complex formation. Energy‐minimized gas‐phase geometries and vibrational frequencies were obtained for the model compounds O₃Xe(NCCH₃)_n (n=1–3) and O₃Xe(NCCH₃)_n?[O₃Xe(NCCH₃)₂]₂ (n=1, 2). Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM), electron localization function (ELF), and molecular electrostatic potential surface (MEPS) analyses were carried out to further probe the nature of the bonding in these adducts.     

Synthesis of Lanthanide Coordination Polymers with Benzophenone-4,4-dicarboxylate: Effect of Lanthanide Contraction on Structures

Introduction Recently, the coordination polymers based on dicar-boxylic acid have been studied extensively for their importance as promising materials.1-7 So the rational design and synthesis of novel coordination polymers with useful functions attract considerable attention. As well known, the design of extended structure with po-tential applications can be realized by starting with connecting ligands capable of binding metal centers strongly and predictably to afford the structures with expe…     

Synthesis, Characterization and Crystal Structures of Lanthanide Phenoxyacetate Complexes with 1,10-Phenanthroline

IntroductionTherehasbeenconsiderableinterestinthecoordinationchemistryoflanthanidecomplexeswithcarboxylateligandsduetotheirpotentialapplicationinmolecularassembliesandluminescentprobesinsystemsofbiologicalrelevance .1 4 Ofthenumerouslanthanidecomplexesthathavebeenwidelystudied,5 9mostofthemarefoundtoexhibitavarietyofdimericorinfinitechainstructure.RecentlywehavereportedpolymericLu(POA) 3(phen)compoundinwhichlutetiumionsforminfinitechainalongtheb axisdirectionthroughthecoordinationofbridgingc…     

新型柱-层结构的金属有机配位聚合物的合成与性质

利用5-磺基间苯二甲酸单钠盐（NaH₂L）和La(NO₃)₃在水热条件下成功合成了一种新型配位聚合物[La(L)(H₂O)₃]_n·nH₂O（1, CCDC: 1422966）,其结构和性质经IR, X-射线单晶衍射,元素分析,热重分析和FL表征。结果表明：La³⁺为九配位,呈三帽三棱柱配位构型。化合物1基于La³⁺和L^3-配体的两种拓扑非等价节点,呈现出五连接3D柱层状金属有机骨架结构,Schlafli符号为(4⁵, 6⁵)。化合物¹的荧光发射峰位于410 nm,归属于配体到金属的电荷转移。     

Synthesis, Structure and Properties of a Novel Chloro-Oxo Alkoxide: Sr2Er2OCl(OPr i )7(HOPr i )4

A new chloro-oxo-alkoxide, Sr₂Er₂OCl(OPr ⁱ )₇(HOPr ⁱ )₄ has been prepared by reacting 4ErCl₃ with 5Sr dissolved in toluene:HOPr ⁱ . The structure, determined by single-crystal X-ray techniques, is built from two polymer strands, each formed by repeating two molecular Sr₂Er₂O(OPr ⁱ )₇(HOPr ⁱ )₄ complexes, inter-tied by a chloro atom. The four independent, but very similar complexes contain two Er and two Sr ions, all binding to a central oxo ion. The great similarity of the FT-IR and UV-vis-NIR spectra of the solid and the hexane/toluene/2-propanol solutions shows that the molecular complexes have similar complex structures in the solid state and in solution.     

Syntheses and Structures of Three Novel 1-D Lanthanide-isonicotinate Coordination Polymers

1 INTRODUCTION In the past decade or so far, the construction of extended multidimensional coordination polymers comprised of metal ions as nodes and bridged ligand as linkers or spacers of self-assembly has attracted considerable attention in supramolecular and materi- als chemistry due to the formation of the intriguing topological structures and potential applications as functional materials[1～4]. In construction of these ex- tended structures, selection of the polydentate orga- nic li…     

Syntheses and Crystal Structure of Erbium(Ⅲ) Coordination Polymers with Two Flexible Double Betaine Ligands

1INTR0DUCTI0NLanthanidecarboxylatecomplexeshavebeenwidelystudiedt1iandm0starefoundtoexhibitavarietyofdimericorinfinitechainstructures.Recentstudiesinourlaboratoryhavedem0nstratedthattheprototypetertiaryaminebetaine(Me,N CHzC0z-)anditsderivativesareusefulinthegenerationoflanthanidecarb0xylate-likecomplexeswithnewstructuralfeaturesduetotheiroverallchargeneutralityandpossibleinclusionofvariouskindsofcounteranionsinthestructuret2~4i.Thelan-thanidecomplexesisolatedsofarhavebeenfoundtobemononu…     

基于2-氨基对苯二甲酸的镉配位聚合物的合成、晶体结构和性质研究

以2-氨基对苯二甲酸根离子(AT)为配体,合成了3个结构新颖的镉配位聚合物:[Cd(AT)(H2O)]n(1)、[Cd(AT)(Py)]n(2)和[Cd(AT)(BPP)]n(3)(AT=2-氨基对苯二甲酸根离子,Py=吡啶,BPP=1,3-二(4-吡啶基)丙烷)。晶体结构表明,随着辅助配体的改变,AT表现出3种不同的配位模式,分别形成rtl(1)、ths(2)和sql(3)3种不同的拓扑结构。由于分子内/分子间氢键、芳香环之间的π…π堆积与C-H…π相互作用,使得3个化合物展现出较好的热稳定性。     

基于2-氨基对苯二甲酸的镉配位聚合物的合成、晶体结构和性质研究

以2-氨基对苯二甲酸根离子（AT）为配体,合成了3个结构新颖的镉配位聚合物：[Cd（AT）（H₂O）]_n（1）、[Cd（AT）（Py）]_n（2）和[Cd（AT）（BPP）]_n（3）（AT=2-氨基对苯二甲酸根离子,Py=吡啶,BPP=1,3-二（4-吡啶基）丙烷）。晶体结构表明,随着辅助配体的改变,AT表现出3种不同的配位模式,分别形成rtl（1）、ths（2）和sql（3）₃种不同的拓扑结构。由于分子内/分子间氢键、芳香环之间的π…π堆积与C-H…π相互作用,使得3个化合物展现出较好的热稳定性。     

Binding of permanganate anion to pentaammineazidocobalt(III) cation in solution and solid phases: synthesis,characterization, X-ray structure,and genotoxic effects of [Co(NH3)5N3](MnO4)2⋅H2O

A pentaammineazidocobalt(III) complex, [Co(NH₃)₅N₃](MnO₄)₂XH₂O has been synthesized by an one-pot synthesis method. It was characterized by studies such as infrared (IR) and UV-visible spectroscopy. The single crystal X-ray structure analysis revealed that the title complex crystallizes in space group Cc. The cobalt center is six coordinated with slightly octahedral geometry. The supramolecular architecture is also formed by intermolecular N-H…O (anion and H₂O) and Mn-O…O-H hydrogen bonds. The binding property of the cation, [Co(NH₃)₅N₃]²⁺ with the anion, MnO₄^– has also been determined (in solution phase) with the help of UV-visible spectroscopic titrations. Further, the genotoxic effects of KMnO₄, [Co(NH₃)₅N₃]Cl₂ and [Co(NH₃)₅N₃](MnO₄)₂XH₂O were studied using Allium cepa root chromosomal aberration assay and it revealed that the genotoxicity of the newly synthesized complex is 1.97–1.76 fold, which is less compared to KMnO₄. The order of genotoxic potential has been observed to be KMnO₄ > [Co(NH₃)₅N₃](MnO₄)₂XH₂O > [Co(NH₃)₅N₃]Cl₂.     

系列Ag-Ln配位聚合物的合成、结构及发光性能

采用水热合成法,以吡嗪-2-羧酸(2-Hpzc)、3,5-吡啶二羧酸(3,5-H_2PDA)和草酸(H_2ox)为配体,合成9种Ag-Ln配位聚合物:{[LnAg(2-pzc)_2(ox)]·H_2O}_n(Ln=Pr(1),Nd(2),Sm(3),Eu(4)),[LnAg(3,5-PDA)(ox)(H_2O)]_n(Ln=Pr(5),Nd(6)),[LnAg(3,5-PDA)(3,5-HPDA)(ox)_(0.5)(H_2O)_2]_n(Ln=Sm(7),Dy(8),Ho(9))。配位聚合物1～4是同构的,由2-pzc~-和ox~(2-)连接,而配位聚合物5～9是以3,5-PDA~(2-)和ox~(2-)为桥联配体,均呈现3D网状结构。光物理性能研究表明配位聚合物均表现出Ln(Ⅲ)的特征发射,这可归因于Ag-配体部分(d-block)的敏化作用。另外,在晶体场和Ag(1)离子4d轨道的共同作用下,Ln(Ⅲ)离子的4f轨道被调谐,使部分能级发生明显的位移,表现为相应NIR发射带的位移,在其UV-Vis-NIR吸收光谱中可以得到佐证。     

Synthesis,Charactarization and Crystal Structures of Lanthanide Phenoxyacetate Complexes with1,10—Phenanthroline

Three new lanthanide phenoxyacetate complexes with 1,10‐phenanthroline. [Nd(POA)₃ (phen)]₂ · 2C₂H₅OH (1), [Eu(POA)₃‐ (phen)]₂ · 2C₂H₅OH (2) and [Sm(POA)₂(DMSO)(phen)]₂‐ (ClO₄)₂ (3) (POA= phenoxyacetate, phen = 1,10‐phenanthroline, DMSO = dimethyl sulfoxide), were synthesized and characterized by elemental analyses, IR, UV‐vis and FAB‐MS spectra. Their structures were determined by single crystal X‐ray diffraction analysis. In complexes 1 and 2, the carboxylate groups are bonded to Ln³⁺ ion in three modes: the chelating bidentate, the bridging bidentate and the bridging tridentate. In complex 3, the carboxylate groups are bonded to Sm³⁺ ion only involved in one mode: the bridging bidentate. The luminescence behavior of complex 2 was also studied by means of emission spectra.     

柔性环己烷六酸和刚性草酸配体桥连的稀土配位聚合物的水热合成与结构研究

草酸铽与水合环己烷六酸(H6LⅠ.H2O)(顺式椅式构型LⅠ:a,e,a,e,a,e)在水热条件下反应生成一种新颖的三维稀土配位聚合物[Tb4(LⅡ)(ox)3(H2O)8](LⅡ为反式椅式构型:e,e,e,e,e,e;ox为草酸根),通过元素分析和红外光谱对这个配位聚合物进行了表征。X射线单晶衍射分析表明该配合物属于三斜晶系,P1空间群,晶胞参数为:a=0.60203(4)nm,b=1.08278(8)nm,c=1.29446(9)nm,α=67.908 0(10)°,β=82.109 0(10)°,γ=83.887 0(10)°,V=0.773 07(9)nm3,Z=2。在这个配合物的形成中,顺式构型的H6LⅠ配体发生构型转变形成LⅡ配体,LⅡ配体采取μ8-桥连模式将Tb离子连接成一个具有孔洞的二维(Tb-LⅡ)配位层。由μ2-和μ4-桥连模式构成的一维(Tb-ox)链将二维(Tb-LⅡ)层连接成一个具有孔道的三维配位框架,ox配体和水分子通过配位作用和氢键作用填充在孔道中。     

两个新型锌的配位聚合物的合成与晶体结构

本文以Zn(NO3)2.6H2O分别与1,3,5-均苯三甲酸(1,3,5-H3BTC)和2,5-噻吩二羧酸(2,5-H2TDC)通过水热/溶剂热反应合成了2个锌的配位聚合物[Zn3(OH)(BTC)2(C4N2H11)(H2O)]n(1)(C4N2H11=质子化的哌嗪)和[Zn(2,5-TDC)(i-PrOH)]n(2)。并对配位聚合物1和2进行了元素分析、FTIR和X-射线单晶结构解析等表征。X-射线单晶结构解析表明配位聚合物1和2的晶体均属于正交晶系,空间群分别为Pbca和P212121。化合物1中含有Zn3O结构单元,Zn3O结构单元通过BTC的连接构成1个层状结构,层状结构再通过堆积形成1个三维结构。化合物2中含有无机的Zn-O链。无机Zn-O链通过TDC配体与相邻的6个无机Zn-O链相连形成三维开放式的框架结构。     

Zn(NCS)2‐3‐cyanopyridine Coordination Compounds: Synthesis,Crystal Structures,and Thermal Properties

The reaction of different stoichiometric amounts of Zn(NCS)₂ with 3‐cyanopyridine in different solvents leads to the formation of several new coordination compounds, which were structurally characterized and investigated for their thermal behavior. In Zn(NCS)₂(3‐cyanopyridine)₄ ( 1 ) and Zn(NCS)₂(3‐cyanopyridine)₂(H₂O)₂ · (3‐cyanopyridine)₂ ( 2 ) the zinc cations are octahedrally coordinated by two terminally N‐bonded thiocyanate anions and four 3‐cyanopyridine ( 1 ) or two 3‐cyanopyridine and two water molecules ( 2 ) within slightly distorted octahedra. Zn(NCS)₂(3‐cyanopyridine)₂ ( 3 ) and Zn(NCS)₂(3‐cyanopyridine)₂ · (H₂O)_0.5 ( 3‐H₂O ) also form discrete complexes but with tetrahedrally coordinated Zn cations. Upon heating compound 1 decomposes without the formation of any intermediate compound. In contrast, compound 2 loses the water molecules in the first step and transforms into compound 1 . Surprisingly, upon further heating a second TG step is observed, in which compound 3 is formed as an intermediate, which is not observed if compound 1 is heated directly. The tetrahedral complex 3 melts leading to the formation of an amorphous phase. If the hemihydrate 3‐H₂O is heated, it transforms into 3 via melting and crystallization but there are hints that a metastable phase might form as intermediate on water removal.     

三个异质同晶喹啉-8-氧醚乙酸配位聚合物的合成、结构及磁性质

本文通过溶剂热反应合成了3个异质同晶的配位聚合物[Ni(8-qoac)Cl]n(1,8-Hqoac=喹啉-8-氧醚乙酸),[Fe(8-qoac)Cl]n(2)和[Mn(8-qoac)Cl]n(3)。单晶结构分析表明,这些配合物结晶在Pbca空间群中,其中八面体配位的金属离子首先被2个氯离子桥连形成1个双核结构,双核单元再通过4个反-反配位模式的羧酸根与4个相邻的双核单元连接,形成1个以双核为节点的(4,4)网二维层状结构。磁学表征发现化合物1表现出类自旋倾斜的磁行为,而2和3只表现出简单的反铁磁行为,表明了金属离子的各向异性等特点对磁学行为会产生重要的影响。     

Synthesis, Crystal Structure, Magnetism, and Optical Properties of Gd3[SiON3]O—An Oxonitridosilicate Oxide with Noncondensed SiON3 Tetrahedra

The novel oxonitridosilicate oxide (sion oxide) Gd₃[SiON₃]O was obtained by the reaction of gadolinium metal with its carbonate oxide and silicon diimide in a radiofrequency (r.f.) furnace at a temperature of 1400°C. The crystal structure of Gd₃[SiON₃]O (I4/mcm, a=649.1(2) pm, c=1078.8(6) pm, Z=4, R₁=0.0411, wR₂=0.0769, 405 F² values, 19 parameters, 123 K) is isotypic with that of Ba₃[SiO₄]O and Cs₃[CoCl₄]Cl. It can be derived from the perovskite structure type by a hierarchical substitution: Ti⁴⁺→O^2-, O^2-→Gd³⁺, Ca²⁺→[SiON₃]^7- resulting in the formation of large [OGd₆]¹⁶⁺ octahedra, which are twisted by ξ=16.47(1)° around [001]. The low-temperature single-crystal data investigation led to a crystallographic splitting of the central O atom which could not be resolved at room temperature. The UV-Vis absorption spectra in reflection geometry of the yellow title compound revealed two overlaying broad bands, one peaking at almost the same wavelength as observed in gadolinium oxide (340 nm) and a second red-shifted band at approximately 400 nm indicating a strong influence of nitrogen on the ligand field splitting of the 5d states of Gd³⁺. Temperature-dependent magnetic susceptibility measurements of Gd₃[SiON₃]O show Curie-Weiss behavior from 2 to 300 K with an experimental magnetic moment of 7.68(5) μ_B/Gd, indicating trivalent gadolinium. There is no evidence for magnetic ordering down to 2 K. According to the paramagnetic Curie temperature of −7(1) K, the exchange between the gadolinium magnetic moments is supposed to be only weak. The vibrational spectroscopic data (IR and Raman) are reported.     

Synthesis and Crystal Structure of the Novel Compound Mg4.5Pr79.5Mo126O312 Containing Mo3, Mo7 and Mo19 Clusters

The synthesis and crystal structure of the novel reduced molybdenum oxide Mg_4.5Pr_79.5Mo₁₂₆O₃₁₂ are presented. This compound crystallizes in the trigonal space group R-3 m with a = 11.3061(2) Å, c = 58.242(1) Å, V = 6447.5(2) Å³, and Z = 1. Refinements yield R(F ²) = 0.0433 and wR(F ²) = 0.0931 for 2827 unique reflections. The structure is built up from alternating slabs made up of molybdenum forming Mo₃, Mo₇ and Mo₁₉ clusters, praseodymium and oxygen atoms, and slabs containing isolated MoO₆ octahedra. The Pr³⁺ cations are localized either within the slabs or at their borderlines to ensure the cohesion between the slabs. Of the six crystallographically independent sites occupy by the Pr³⁺ cations, two of them also contain randomly about 15% and 20% of Mg²⁺ cations while the remaining four are fully occupied by the Pr³⁺ cations.