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1.
用溶剂热方法合成了[Me4N]2HgGe4S10, 通过单晶X射线衍射, IR, DSC-TG手段对其进行了表征. 结果表明, 标题化合物属四方晶系, I-4空间群, 晶胞参数a=0.92687(8) nm, c=1.43739(12) nm, V=1.23484(18) nm3, Z=2, Mo Kα λ=0.071073 nm, R1=0.0570, wR2=0.1374, 空旷骨架结构由超四面体Ge4S10与HgS4四面体共用顶点连接而成, 有机模板离子在一维孔道中. 该化合物具有一定的热稳定性, 在320 ℃发生分解形成GeS2.  相似文献   
2.
以哌嗪为模板剂,在水-乙醇混合溶剂体系中溶剂热合成了两个具有三维开放骨架结构的稀土硫酸盐[Ln4(H2O)4(SO4)10](C4N2H12)4(H2O)4(Ln = Gd,化合物1和Eu,化合物2),并对其进行了结构表征、热重以及荧光光谱分析. 单晶结构解析表明,化合物1和2属于同构异质,均结晶于单斜晶系,P21/c空间群,化合物1,a = 19.691(3) ?,b = 19.249(3) ?,c = 13.186(2) ?,β = 92.33(0)o,V = 4993.5(1) ?3, Z =4. 化合物2,a = 19.7233(8) ?,b = 19.2791(8) ?,c = 13.2095(5) ?,β = 92.329(1)o,V = 5018.7(3) ?3, Z =4. 两个化合物在ab平面上由SO4,GdO8和GdO9多面体共边或共角交错连接形成含有八元环和十六元环的二维层状结构,该二维层沿c方向平行排列,相邻层通过SO4四面体相连形成具有孔道的三维开放骨架结构,其孔道之中包含平衡骨架负电荷的质子化哌嗪分子. 化合物2的固体荧光光谱分析显示其在397nm激发波长下,表现出典型的Eu3+发光性质.    相似文献   
3.
A new vanadium(III) phosphite, (C4H8N2H4)0.5(C4H8N2H3)[V4(HPO3)7(H2O)3]1.5H2O, has been synthesized hydrothermally by using V2O5, H3PO3 as reactants, piperazine as the structure-directing agent. The as-synthesized product was characterized by powder X-ray diffraction, IR spectroscopy, inductively coupled plasma analysis, thermogravimetric analysis, and SQUID magnetometer. Single-crystal X-ray diffraction analysis shows that the title compound crystallized in the trigonal space group (No. 165) with the parameters: , , and Z=4. Its structure is built up by alternation of octahedral VO6 or VO5(H2O) and pseudo-pyramidal HPO3 units to form infinite 2D layers, and these layers are interconnected by sharing vertex-oxygen with octahedral VO6 units to generate a 3D open-framework structure with 12-membered ring channels in a and b directions, respectively, where there exist entrapped diprotonated and mono-protonated piperazine cations, and water molecules. Magnetic measurement indicates that paramagnetic behavior is observed down to 4 K.  相似文献   
4.
以1,3-丙二胺为模板,水热合成了三维孔道结构钒磷酸盐[H3N(CH2)3NH3]2[H3N(CH2)3NH2][H2N(CH2)3NH2][V(H2O)2(VO)8(OH)4(PO4)4(HPO4)4]·4H2O(DAP-V9P8).用单晶X射线衍射、红外光谱和热重法对该化合物的晶体结构进行了表征.DAP-V9P8的无机骨架由[VO5]、[VO6]、[PO4]和[HPO4]通过共顶点连接而成.孔道中充填的丙二胺分子随所处结晶学位置不同,有三种完全不同的分子构象.其中,位于//b轴直径达1.82nm椭圆形孔道中心的丙二胺分子碳链呈独特的直线状分布.晶体学参数:a=1.4820(9)nm,b=1.0255(4)nm,c=1.8181(9)nm,β=90.391(8)°;P21/n(No.14);R1=0.0772,wR2=0.2004(I>(2σI)).与等结构的其它化合物进行了系统的结构比较.  相似文献   
5.
1 INTRODUCTION even three-dimensional (3-D) extended solid frame- works in appropriate ways is a major challenge in The syntheses and characterizations of novel po- POMs chemistry. Based on the fact that POMs fra- lyoxometalates (POMs) have currently attached in- meworks with high electronic density can act as un- creasing interest owing to not only enormous variety usually effective ligands to coordinate second tran- of intriguing structural topologies, but also their fas- sition meta…  相似文献   
6.
为了丰富亚磷酸盐结构,为多孔材料的定向合成提供一定的实验数据,在溶剂热的条件下,以咪唑为结构导向剂合成了一个具有三维开放骨架结构的新型亚磷酸镓化合物Ga8(H2O)6(HPO3)14·(C3N2H6)3·H3O(化合物1),并通过粉末X-射线衍射、红外光谱、热重、ICP和CHN元素分析对化合物进行了表征。单晶X-射线衍射分析结果表明,化合物1属于三斜晶系,P-3c1空间群,晶胞参数为a=b=1.33388(8)nm,c=1.7886(2)nm,γ=120(4)°,Z=2。其结构是由Ga O6八面体和[HPO32-]假四面体单元相互连接构成。该结构沿着[100]和[010]方向具有12元环孔道。值得注意的是,在化合物1的结构中存在两种不同的次级结构单元(SBU):经典的6*1单元Ga3P4和齿轮状的Ga P6单元。  相似文献   
7.
A key challenge for potassium‐ion batteries is to explore low‐cost electrode materials that allow fast and reversible insertion of large‐ionic‐size K+. Here, we report an inorganic‐open‐framework anode (KTiOPO4), which achieves a reversible capacity of up to 102 mAh g?1 (307 mAh cm?3), flat voltage plateaus at a safe average potential of 0.82 V (vs. K/K+), a long lifespan of over 200 cycles, and K+‐transport kinetics ≈10 times faster than those of Na‐superionic conductors. Combined experimental analysis and first‐principles calculations reveal a charge storage mechanism involving biphasic and solid solution reactions and a cell volume change (9.5 %) even smaller than that for Li+‐insertion into graphite (≈10 %). KTiOPO4 exhibits quasi‐3D lattice expansion on K+ intercalation, enabling the disintegration of small lattice strain and thus high structural stability. The inorganic open‐frameworks may open a new avenue for exploring low‐cost, stable and fast‐kinetic battery chemistry.  相似文献   
8.
Kinetics of the thermal decomposition of 3-methylaminopropylamine which was used as a structure-directing agent in the synthesis of AlPO4-21 has been studied under isothermal and non-isothermal conditions. The decomposition is a single-step reaction occurring in the 573–663 K range. It is a phase-boundary-controlled process, described by the ‘F2/3, R3’ kinetic model. The activation energy values obtained under the non-isothermal and isothermal conditions lie in the 173–151 kJ mol–1 range.  相似文献   
9.
The preparation of inorganic compounds, exhibiting open-framework structures, by hydrothermal methods has been presented. To illustrate the efficacy of this approach, few select examples encompassing a wide variety and diversity in the structures have been provided. In all the cases, good quality single crystals were obtained, which were used for the elucidation of the structure. In the first example, simple inorganic network compounds based on phosphite and arsenate are described. In the second example, inorganic-organic hybrid compounds involving phosphite/arsenate along with oxalate units are presented. In the third example, new coordination polymers with interesting structures are given. The examples presented are representative of the type and variety of compounds one can prepare by careful choice of the reaction conditions.  相似文献   
10.
Employing 4,4-trimethylenedipyridine as a template,a new two-dimensional zinc phosphite (4,4-(C5H4N)2(CH2)3)· [Zn3(HPO3)4 ] has been prepared at room temperature and characterized by single-crystal X-ray diffraction,FTIR,elemental analysis,powder X-ray diffraction,and thermogravimetric analysis.The compound crystallizes in the monoclinic space group P2 1 /c,with cell parameters,a=9.3309(19),b=14.798(3),c=33.637(7),β=91.11(3),V=4643.8(16) nm 3 and Z=4.The connectivity of the ZnO4 tetrahedra and HPO 3 pseudo pyramids results in infinite corner-sharing 4-membered ring chains as second building units which are further linked by Zn O P bonds to form a 2-D layer that with interesting 8-membered ring channels along the [100] direction.The diprotonated 4,4-trimethylenedipyridine molecules sit in the middle of the layers along the [100] direction and interact with the framework via hydrogen bonds.  相似文献   
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