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1.
A novel zinc(H) metal phosphonate compound [Zn(phen)(m-OOCC6H4PO3H)] 1 (phen = phenanthroline) has been synthesized under hydrothermal conditions. Single-crystal X-ray structure analysis reveals that compound 1 belongs to the triclinic system, space group P1 with a = 9.3356(19), b = 10.203(2),c = 10.743(2)A,α = 76.3030(70), β= 69.2317(51), y = 84.3833(74)°,V = 929.4(3) ,A3, Z = 2, C2OH15N2O5PZn, Mr = 459.68, Dc = 1.643 g/cm^3,μ= 1.444, mm^-1, F(000) = 468, the final R = 0.0330 and wR = 0.0848. In the structure, the central ion Zn(H) is five-coordinated, linking three O atoms with one from carboxyl and the other two from phosphonyl group. The remained two coordinate sites were occupied by two N atoms from one phen molecule to form the asymmetric unit. Then every two adjacent asymmetric units are bridged by the O atoms from phosphonate group and carboxyl to give rise to a 1D chain along the b axis. These chains are constructed by weak π-π stacking interactions and C-H…π interactions to generate a 3D supramolecular framework.  相似文献   
2.
1 INTRODUCTION Transition metal oxide clusters and their deriva- tives offer an unmatched variety of structural motifs and wide ranging applications in several areas, such as analytical chemistry, materials science and cataly- sis, nanotechnology, chemical sensing, environmental decontamination, biochemical and geochemical pro- cesses, and medicine[1~3]. Polyoxovanadates or vana- dium oxide clusters constitute an important subclass of polyoxometalates and have been studied exten- sively.…  相似文献   
3.
本文对所合成的具有 [(PO4 ) 2 Mo5O1 5]簇骼的 3种新颖的有机 磷钼酸盐簇合物(NH3CH2 CH2 NH3) 2 5[(PO4 ) (HPO4 )Mo5O1 5]·7 5H2 O (Ⅰ ) ,(H3NCH2 CH2 NH3) 3·[(PO4 ) 2 Mo5O1 5]·3H2 O (Ⅱ )和(H3NCH2 CH2 NH3) 2 ·[Cu(en) ][(PO4 ) 2 Mo5O1 5]·5H2 O (Ⅲ )用FTIR ,NIR Raman ,紫外 可见漫反射光谱 (UV VisDRS)和荧光光谱等研究手段 ,对其进行光谱研究 ,探讨其结构和性能的关系。在这些化合物中 ,化合物Ⅰ和Ⅱ具有孤立的 [(PO4 ) 2 Mo5O1 5]簇骼基元 ,而化合物Ⅲ的 [(PO4 ) 2 Mo5O1 5]簇骼基元是由 [Cuen]基团桥联成链 ;磷钼酸盐的特征振动频率和这些化合物的结构相关 ;UV VisDRS显示 ,在 2 0 0和 2 6 0nm左右有两个杂多化合物的特征吸收谱带 ;化合物的稳态荧光光谱中 ,观察到以 2 4 0nm激发 ,在大约 4 0 0nm附近出现的由金属氧簇Oμ→Mo跃迁激发所引起的较强的发射峰 ,在化合物 (Ⅲ )中 ,还观察到通过 [Cuen]的荷移跃迁的以 5 70nm激发所产生的 6 0 4nm的发射峰。  相似文献   
4.
The novel coordination polymer [Pr(BYBA)3(H2O)2]·[Pr(BYBA)3(H2O)] (BYBAH=2-benzoylbenzoic acid) was yielded by hydrothermal synthesis,determined by single-crystal X-ray diffraction,and characterized by FT-IR and UV-Vis spectra. The crystal crystallizes in the triclinic system,space group P1 with a=9.112(3),b=14.644(5),c=27.076(11),α=84.223(3),β= 87.816(4),γ=88.902(4)o,V=3592(2)3,C84H60O21Pr2,Mr=1687.14,Z=2,F(000)=1700,Dc= 1.560 g/cm3,μ=1.419 mm-1,the final R=0.0485 and wR=0.1258 for 13035 observed reflections with I > 2σ(I). The compound contains two different building units,[Pr2(BYBA)6(H2O)4] and [Pr2(BYBA)6(H2O)2]. It is noticeable that [Pr2(BYBA)6(H2O)4] is an isolated binuclear building block,in which the Pr3+ ion centers are both located in an eight-coordinated environment. However,in [Pr2(BYBA)6(H2O)2] the Pr3+ ion centers are located in a nine-coordinated environment and connected by BYBA ligands to form 1D chains.  相似文献   
5.
石墨相氮化碳(g-C3N4)荧光纳米材料具有原料便宜、制备容易、荧光量子产率高、光学稳定性好、毒性低等优点,并且避免有机荧光染料复杂的合成步骤或者金属半导体量子点对环境潜在的危害,这些优点使得g-C3N4纳米材料成为新兴的荧光探针用于检测金属离子。最近,已有文献报道重金属汞离子能够高灵敏高选择性地猝灭g-C3N4量子点的荧光,加入碘离子能够提取被键合的汞离子形成碘化汞(HgI2)进而恢复g-C3N4量子点的荧光,从而建立一种高灵敏检测碘离子的荧光传感器。然而,该方法依然需要重金属汞离子的参与,限制了该方法的推广应用。通过硝酸氧化块体g-C3N4并结合水热法处理制备了一种水溶性好、荧光强度高的g-C3N4量子点。该量子点的荧光发射波长位于368 nm,且其荧光发射波长不随激发波长的改变而改变,表明该量子点的尺寸比较均一。笔者发现碘离子在220 nm处有一个较强的吸收峰,与该量子点的激发光谱(中心波长245 nm)具有较大的重叠,从而产生内滤效应引起该量子点的荧光发生猝灭。利用这一性质,构建了一种选择性检测碘离子的新型荧光传感器。在最优检测条件下,g-C3N4量子点的荧光猝灭强度(ΔF)与碘离子浓度(X,μmol·L-1)在10~400 μmol·L-1之间具有良好的线性关系,线性方程为ΔF=0.325 79X+6.039 05(R2=0.999 5),检出限为5.0 μmol·L-1。通过“混合即检测”并且不需要借助与重金属离子的配位作用就能够检测碘离子,因此该方法具有快速、环保以及操作简便等优点。  相似文献   
6.
The title compound, a novel Ag(Ⅰ) carboxyarylphosphonate [Ag(H2BCP)(4,4'- bipy)]·2H2O (H3BCP = p-H2O3PCH2C6H4COOH, 4,4'-bipy = 4,4'-bipyridine), was synthesized by a hydrothermal reaction and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. It belongs to monoclinic system, space group P21/c with a = 5.7038(11), b = 22.397(4), c = 5.602(4) ?, β = 106.26(3)°, V = 1913.4(7) 3, Z = 4, C18H20N2O7PAg, Mr = 515.20, Dc = 1.788 g/cm3, μ = 1.182 mm-1, F(000) = 1040, the final R = 0.0404 and wR = 0.1216 for 4178 observed reflections with I 2σ(Ⅰ). In the structure, the Ag(Ⅰ) cations are bridged by 4,4'-bipy to give rise to 1D chains running along the b axis. These chains are linked further by the interactions of O (from BCP ligands) and Ag atoms to yield 2D layers. Hydrogen bonding interactions and weak π-π stacking interactions between 4,4'-bipy rings assemble such adjacent layers to generate a 3D supramolecular architecture.  相似文献   
7.
A polyoxovanadium borate [Na(H2O)]2[Na(H2O)2]2[Cu(en)2][V12B18O54(OH)6]·(H3O)2·(H2O)18 1(en = ethylenediamine) has been hydrothermally synthesized and characterized by IR,two-dimensional infrared(2D IR) correlation spectroscopy with magnetic and thermal perturba-tion,thermal IR spectroscopy,thermal gravimetric analysis and single-crystal X-ray diffraction.It crystallizes in triclinic,space group P1 with a = 12.981(3),b = 13.044(3),c = 14.208(3) ,α = 63.98(3),β = 77.17(3),γ = 14.208(3)°,V = 2001.0(8) 3,Z = 1,Mr = 2518.05,Dc = 2.090 g/cm-1,F(000) = 1255.0,Mu(mm-1) = 1.756,λ(MoKα) = 0.71073 ,R = 0.0625 and wR = 0.1952.In 1,the [V12B18O54(OH)6]8-units are connected by [Cu(en)2]2+,binuclear Na(1) and Na(2) to form a three-dimensional porous framework.  相似文献   
8.
为了了解琥珀酸氢十八酯晶体(OHS)的结构,本文测定了OHS晶体几何配置为y^-(zx)y和y^-(zz)y和几何配置为y^-(xz)y和^y-(xx)y的拉曼光谱,实验表明:涉及到OHS烷烃链的几个振动模式都出现偏振动,由此可推测其晶体结构可能是以双聚体沿[100]和[001]方向排列成层,沿[010]方向堆垛,OHS其他基团的拉曼光谱振动吸收峰也都相应出现。  相似文献   
9.
三种不同的钒氧簇合物的合成和光谱研究   总被引:1,自引:0,他引:1  
利用水热法合成了三种钒氧簇合物:[{Ni(phen)2}2V4O12]H2O(Ⅰ),[N(CH2CH2)3NH]Na(H2O)6{K4(H2O)4[V10028]}(H2O)4(Ⅱ)和[(CH3)4N]6[V14O36Cl](Ⅲ).通过用FTIR,UV-Vis DRS和荧光光谱研究了它们的结构和性能的关系.FTIR研究表明,化合物的相关基团的特征振动吸收峰和其结构相关.化合物Ⅰ的固体紫外漫反射光谱在200,230,260和350 nm出现四个宽峰,分别对应Ot→V,Oμ→Ni,Oμ→V荷移和phen的π-π*跃迁.文章还对这三个钒氧簇合物的荧光光谱进行了研究.最后,应用Gaussian98的量子化学计算,说明化合物Ⅰ的结构特点.  相似文献   
10.
马来酸氢十八酯晶体(OHM)的拉曼光谱研究   总被引:2,自引:1,他引:1  
为了进一步了解马来酸氢十八酯晶体(OHM)的结构,本文测定了OHM晶体几何配置为(y(zx)y)和y(xz)y和y(xx)的拉曼光谱。实验表明OHM烷烃链的几个振动模式出现偏振,垛;OHMS其他基团的拉曼光谱振动吸收峰也都具应出现。  相似文献   
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