Synthesis,Crystal Structure and Fluorescence Property of a Zinc(Ⅱ) Coordination Polymer with a Theoretical Calculatio

We have designed and synthesized a new luminescent coordination polymer[Zn₂(NO₃)(NCP)₃(H2O)₃]n·2 nH₂O(1,HNCP=2-(2-carboxyphenyl)imidazo-[4,5-f]-1,10-phenanthroline)under hydrothermal conditions,which has been structurally characterized by single-crystal X-ray diffraction analyses.1 crystallizes in monoclinic,space group P2₁/n,with a=13.7748(3),b=19.2651(4),c=19.9543(4)?,β=95.339(2)o,V=5272.35(19)?³,C₆₀ H_39.73 N₁₃ O_13.33 Zn₂,M_r=1286.80,D_c=1.621 g/cm³,Z=4,μ(Mo Ka)=2.118,F(000)=2629,the final R=0.0598 and w R=0.1483.In 1,the organic ligand NCP-displays two different bridging modes to connect adjacent Zn(II)ions into a 1 D chain along the c-direction.Photoluminescent analyses reveal that 1 exhibits a strong green emission with a fluorescent lifetime of 5.57 ns.The first-principle calculation results show that the luminescence mainly originates from ligand-centered charge transition.     

6,7-二氰基联吡啶喹喔啉的Eu~Ⅲ、Tb~Ⅲ配合物的合成和晶体结构(英文)

6,7-二氰基联吡啶喹喔啉(DICNQ)分别与Eu(NO3)3.6H2O、Tb(NO3)3.6H2O水热反应产生两个新的三价稀土金属-有机配合物[Eu(DICNQ)2(NO3)3].(CH3CN)2(1)和[Tb(DICNQ)(NO3)3]2(2)。X射线单晶衍射研究表明化合物1结晶于单斜晶系,Cc无心空间群,晶胞参数a=1.157 7(6)nm,b=3.193 4(2)nm,c=1.106 6(6)nm,β=97.633(2)°,V=4.055(4)nm3,Z=4,Mr=984.63,Dc=1.613 g.cm-3,μ=1.623 mm-1,F(000)=1 952,S=1.035,T=293(2)K。最终精修结果为:R=0.033 5,wR=0.078 1,I>2σ(I)的点为6 467个。化合物2结晶于三斜晶系,P1空间群,晶胞参数a=0.871 1(3)nm,b=0.890 8(3)nm,c=1.544 9(5)nm,α=80.852(9)°,β=84.217(9)°,γ=65.475(7)°,V=1.076 0(6)nm3,Z=1,Mr=1 254.44,Dc=1.936 g.cm-3,μ=3.356 mm-1,F(000)=604,S=1.026,T=293(2)K。最终精修结果为:R=0.036 8,wR=0.095 6,I>2σ(I)的点为3 697个。化合物1中孤立中性分子之间具有C-H…O氢键作用,而化合物2的晶体结构既包含配体间的π…π堆积作用又有分子间C-H…N和分子内C-H…O氢键作用。     

钒酸镝晶体生长和磁光性能研究

采用液相沉淀法制备了钒酸镝(DyVO4)粉体,使用提拉法生长了DyVO4磁光晶体,通过XRD确定生长的DyVO4晶体没有杂相,晶体的晶胞参数是a =b =0.71434 nm,c =0.6313 nm,α=β=γ=90°,属于四方晶系.晶体经过定向切割加工成c轴晶向的片状和柱状样品.测试了DyVO4晶体样品的光学性能和磁光性能.结果 显示,样品在500～700 nm波长范围内,具有很高的透过率,在76;～ 79;之间,DyVO4晶体对应于532 nm、633 nm和980 nm的Verdet常数分别为-309 rad/m/T、-167 rad/m/T和-64 rad/m/T,性能优于商用磁光晶体TGG,有望在可见光波段实现应用.     

10 lp/mm空间分辨率高能CT系统

报道了基于光阴极S波段电子直线加速器建成的9 MeV高能微焦点射线成像系统“精卫”,X射线束横向尺寸小于100 μm,7 h剂量波动低至1.6%。初步开展成像实验结果表明:双丝像质计清晰分辨13D号丝,丝直径0.05 mm,CT测试卡测得空间分辨率优于10 lp/mm,装置同时兼容电子束能量6～18 MeV可调。     

Syntheses and Crystal Structures of Two New Mercury（Ⅱ） Complexes with Double Betaine Ligands

Reaction of HgCl2 and double betaine ligands in water at about 80 ℃ yielded two new Hg(Ⅱ) complexes,[Hg(L1)Cl2]·H2O 1 and [Hg2(L2)Cl4]·3HgCl2 2(L1 = 1,3-bis(pyridinio-4-carboxylato)-propane,L2 = 1,4-bis(pyridinio-4-carboxylato)-1,4-dimenthylbenzene).Their struc-tures have been characterized by single-crystal X-ray diffraction techniques.The structure of 1 contains 1-D chains,in which the adjacent Hg(Ⅱ) atoms are bridged by L1 ligands in a syn-syn bis-monodentate mode.The chains are further connected through face-to-face π-π stacking interactions between pyridine rings to generate an infinite double-chain network.In 2,two Hg(Ⅱ) atoms are joined by L2 ligands in the same coordination mode as 1 to form an isolated dinuclear structure.The thermal stabilities of both complexes have also been investigated.