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111.
采用X射线吸收近边结构(XANES)谱对多晶Lu2SiO5∶Ce(LSO∶Ce)发光粉体中Ce元素的化合价状态进行了表征,结果表明:在空气下煅烧后得到的不同Ce掺杂浓度的LSO∶Ce粉体中,Ce3+在总掺杂Ce中的含量仅为18%~39%;而经1 000℃/2 h的氢气气氛下退火后,LSO∶0.5%Ce粉体中Ce3+的相对含量由39%大幅提高到83%。真空紫外(VUV)激发发射光谱表明:当Ce的掺杂摩尔分数为0.25%~1%时,Ce3+的摩尔分数与LSO∶Ce粉体的发光强度具有很好的关联性。氢气退火处理可以使LSO∶Ce粉体的发光强度提高近40%。LSO∶Ce粉体在变温条件(50~250 K)下的发射强度表现出良好的稳定性,未观察到热猝灭现象发生。 相似文献
112.
由6,6-四亚甲基苯并富烯C9H6C(CH2)4与Ru3(CO)12在二甲苯中加热回流,合成了一个钌配合物[((η5-C9H6)C(C4H7))2Ru2(μ-CO)2(CO)2]。通过元素分析、红外、热重、核磁共振进行了表征及研究。用X射线单晶衍射法测定了[((η5-C9H6)C(C4H7))2Ru2(μ-CO)2(CO)2]的结构,结果表明:晶体属于单斜晶系,P21/c空间群,a=0.757 1(13)nm,b=1.577 7(3)nm,c=1.107 3(19)nm,β=90.07(2)°,V=1.322 6(4)nm3,Dc=1.699 g.cm-3,μ=1.179 mm-1,F(000)=676,Z=2,R1=0.030 5,wR2=0.072 4。 相似文献
113.
Two cationic iridium(III) complexes, [(pqcm)2Ir(pybz)](PF6) (Ir1) and [(pqcm)2Ir(apybz)](PF6) (Ir2) (pqcmH=2-phenyl-quinoline-4-carboxylic acid methyl ester, pybz=2-pyridyl-benzimidazole, apybz=1-allyl-2-pyridyl-benzimidazole), were readily synthesized from the reaction of IrIII-μ-chloro-bridged dimer [Ir(pqcm)2(Cl)]2 and corresponding ancillary ligands, and characterized by NMR and mass spectroscopies. The structure of Ir2 was also confirmed by single-crystal X-ray diffraction. The photophysical properties of the two complexes were also investigated. Ir1 shows deep red emission peaked at around 652 nm with the phosphorescence quantum yield of ca. 0.29 and the emission lifetime of 233 ns, while Ir2 shows red emission peaked at around 615 nm with the phosphorescence quantum yield of ca. 0.13 and the emission lifetime of 430 ns. The active hydrogen on pybz ligand is believed to have a great influence on the photophysical properties of Ir1. 相似文献
114.
Complex [Sr2(pdc)2(H2O)7]·H2O(1, H2 pdc=2,3-pyrazinedicarboxylic acid) has been synthesized and characterized by single-crystal X-ray diffraction studies and FT-IR. Structural determination reveals that there are two crystallographically independent strontium ions in 1. The coordination geometry of Sr(1) is a nine-coordinated distorted monocapped tetragonal antiprism, while Sr(2) is a nine-coordinated distorted monocapped tetragonal prism. The ligand pdc 2- takes two different connecting modes and links Sr(Ⅱ) centers to generate a 2D layer structure. The 2D layers are linked through O-H···O and O-H···N hydrogen bonds to form a 3D framework structure. Thermal stability and luminescent properties of complex 1 are investigated. 1 belongs to the monoclinic system, space group P21/n with a=10.7182(10), b=7.0377(6), c=29.225(3) , β=95.7170(10)o, Z=4, V=2193.5(3) 3 , M r=651.56, D c=1.973 g/cm 3 , F(000)=1296, μ=4.951 mm -1 , the final R=0.0318 and wR=0.0726 for 3938 observed reflections with I > 2σ(I). 相似文献
115.
A metal-organic coordination polymer [Cd2(PDC)2(bix)(H2O)2]n ·nH2O(H2PDC=2,4-pyridinedicarboxylic acid, bix=1,4-bis(imidazol-1-ylmethyl)-benzene) 1 has been hydrothermally synthesized and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. Brown crystals crystallize in the orthorhombic system, space group P2 12 12 1 with a=11.741(3), b=14.190(4), c=18.963(5) , V=3159.4(14) 3 , C28H26Cd2N6O11, Mr=847.35, Dc=1.781 g/cm3 , F(000)=1680, Z=4, μ(MoKα)=1.415 mm 1 , the final R=0.0381 and wR=0.0882 for 5472 observed reflections (I >2σ(I)). The structure of 1 exhibits a threedimensional network structure. 相似文献
116.
A new complex, [Ni3(L)2(BTA)2]·2H2O (1, L=1,4-di(1H-imidazol-4-yl)benzene, H3BTA=benzene-1,3,5-triacetic acid), has been hydrothermally prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis, TG and PXRD. The complex crystallizes in monoclinic, space group P1 with a=9.0303(12), b=10.0796(13), c=12.7966(17) , α=99.268(2), β=94.490(2), γ=103.722(3)o, V=1108.5(3) 3 , Z=2, C48H38N8O14Ni3 , Mr=1126.99, Dc=1.688 g/cm3 , μ=1.344 mm-1 , S=1.001, F(000)=578, the final R=0.0389 and wR=0.0895 for 3083 observed reflections (I > 2σ(I)). In the title complex, the flexible BTA3- ligands utilize oxygen atoms of carboxylate groups to coordinate with Ni(II) ions to form two-dimensional double-layer networks which are further pillared into a three-dimension framework via the rigid ditopic ligand L. Topological analysis revealed that complex 1 is a typical (3,8)-connected tfz-d 3D network based on the trinuclear [Ni3(CO2)6N4] subunits. 相似文献
117.
The crystal structure of 1,7,8,9-tetrachloro-4-benzyl-10,10-dimethoxy-4-azatricyclo-(5,2,1,02,6)dec-8-ene-3,5-dione (C18H15Cl4NO4, Mr=451.11) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21 /c with a=18.6488(2), b=13.06430(10), c=16.1086(2) , β=92.9870(10)°, V=3919.26(7) 3 , Z=8, D c=1.529 g/cm 3 , μ=5.711 mm -1 , F(000)=1840, the final R=0.0599 and wR=0.1664 for 5645 observed reflections. The title compound is composed of a polycyclic fused pyrrolidine ring system. Three symmetric fused five-membered-ring structures were formed by the Diels-Alder reaction between N-benzylmaleimide and 5,5-dimethoxy-1,2,3,4-tetrachlorocydopentadiene. 相似文献
118.
A novel fluorene derivative containing triphenylamine groups, 2,7-bis[4-(diphenylamino)-phenyl]fluorene (C49H36N2 , Mr= 652.80), was synthesized via Suzuki coupling reaction (yield: 19%) and its crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.320(4), b = 11.250(6), c = 17.369(6) , α = 88.035(3), β = 86.450(5), γ = 73.524(5)°, V = 1742.8(13) 3 , Z = 2, Dc = 1.244 g/cm 3 , μ(MoKα) = 0.072 mm -1 , F(000) = 688, S = 1.095, the final R = 0.0616 and wR = 0.1878. It presents a linear framework constituted by a linkage of fluorene as a bridge and two triphenylamine groups. Its spectral and electrochemical properties were studied by UV-Vis absorption, fluorescence spectroscopy and cyclic voltammetry (CV). This compound can emit intense blue fluorescence with a peak wavelength of 446 nm and a full width at half maximum (FWHM) of 38 nm under UV excitation at 350 nm in film. The highest occupied molecular orbital (HOMO) energy level, the lowest unoccupied molecular orbital (LUMO) energy level and optical band gap (Eg) of the title compound are -5.46, -2.57 and 2.89 eV, respectively. 相似文献
119.
A new coordination compound [Ba(OBPT)2(H2O)2]·H2O was obtained at room temperature by the reaction of 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol(HOBPT) with BaCl2.It was characterized by elemental analysis,FTIR,TG analysis,powder X-ray diffraction analysis and single-crystal X-ray diffraction analysis.The complex crystallizes in the monoclinic P21/n space group,with a = 16.325(1),b = 6.7977(5),c = 24.164(2) ,β = 104.009(1),V = 2601.8(3) 3,Z =4,C26H22BaN10O5,Mr = 691.88,Dc = 1.766 g/cm3,F(000) = 1376 and μ(MoKα) = 1.587 mm-1.The final R = 0.0282 and wR = 0.0724 for 5095 observed reflections with I > 2σ(I) and R = 0.0312 and wR = 0.0744 for all data.In the complex,the barium ion is ten-coordinated with six nitrogen atoms from two ligands,two deprotonated hydroxyl oxygen atoms from another two ligands and two coordinated water molecules to form a double stranded chain.The extensive supramolecular interac-tions lead to the formation of an infinite 2D framework. 相似文献
120.
Divanadium(Ⅴ) complex [VO(aptch)(μ-OCH3)]2(1) and two monovanadium(Ⅴ) complexes [VO(apfah))(OEt)](2a and 2b,H2aptch = 2-hydroxyacetophenone thiophene-2-car-boxylic hydrazone,H2apfah = 2-hydroxyacetophenone 2-furoic acid hydrazone) have been synthesized and characterized.Single-crystal X-ray diffraction studies reveal that 1 is a cen-trosymmetric dimer bridged by two methoxido O-atoms.Complex 1 crystallizes in the monoclinic crystal system,space groups P21/c with a = 7.4825(4),b = 17.0928(11),c = 11.6961(7) ,β = 98.172(4)o,Z = 2,F(000) = 728,μ = 0.829 mm-1,the final R = 0.0457 and wR = 0.1137 for 2654 observed reflections with I > 2(I).The vanadium(V) is coordinated to the tridentate ligand,ethanol molecule to form a distorted square-pyramidal geometry,complexes 2a and 2b.Although 2a and 2b have the same asymmetric unit,they belong to different space groups.Complex 2a crystallizes in the monoclinic crystal system,space groups P21/n with a = 10.2293(2),b = 15.6660(3),c = 10.6298(2) ,β = 116.259(1)o,Z = 4,μ = 0.676 mm-1;complex 2b crystallizes in the triclinic crystal system,space groups P with a = 8.2808(4),b = 9.4704(5),c = 10.0819(5) ,α = 86.133(3),= 81.956(3),γ = 80.248(3)o,Z = 2 and μ = 0.670 mm-1.The hydrogen bonds are found to exist in 2b only.The crystal structure is stabilized by intermolecular hydrogen bonds of C-H···O. 相似文献