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西南官话“二X”结构的将来时间指称功能
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作者 罗天华 邓舒文 《语言研究》 CSSCI 北大核心 2023年第2期43-47,共5页
文章讨论西南官话三种“二X”结构的将来时间指称功能:“二天”“二回”和“二盘”分别表示远将来、中/远将来和中将来。三者的结构和功能存在差别,后两个还可表序数义。这种“二X”结构的将来时间指称功能颇具特色,反映了数量、事件与... 文章讨论西南官话三种“二X”结构的将来时间指称功能:“二天”“二回”和“二盘”分别表示远将来、中/远将来和中将来。三者的结构和功能存在差别,后两个还可表序数义。这种“二X”结构的将来时间指称功能颇具特色,反映了数量、事件与时间范畴之间有密切的关联。 展开更多
关键词 将来时间指称 西南官话 “二x”结构
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Synthesis and Crystal Structure of the Copper(Ⅱ) Complex with 1,10-Phenanthroline-5,6-dione
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作者 LIUHe BUXian-He 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第6期601-604,共4页
The complex Cu(phon)(NO3)2(CH3CN) (phon = 1,10-phenanthroline-5,6-dione) has been synthesized and characterized by elemental analysis, infrared and UV-Vis spectra. X-ray diffraction analysis at room temperature indica... The complex Cu(phon)(NO3)2(CH3CN) (phon = 1,10-phenanthroline-5,6-dione) has been synthesized and characterized by elemental analysis, infrared and UV-Vis spectra. X-ray diffraction analysis at room temperature indicates that the complex crystallizes in orthorhombic system, space group P212121 with a = 8.353(1), b = 11.299(2), c = 17.764(2) A, V= 1676.5(4) A3, Z = 4, C14H9CuN5O8, Mr = 438.8, Dc = 1.739 g/cm3, F(000) = 884 and μ(MoKα) = 1.361 mm-1. The final R and wR factors for the observed reflections with I > 2σ(I) are 0.0353 and 0.0855, respectively. R = 0.0432 and wR = 0.0899 for all data. The structure of the title complex consists of a neutral mononuclear entity. The central Cu (II) atom is five-coordinated by two nitrogen donors of one ligand, two unidentate NO3- ions and one CH3CN molecule. The coordination geometry of Cu (II) can be considered as a distorted trigonal bipyramidal configuration. The complex ability of the NO3-ion has more effect than that of the ClO4- ion on the structure of the complex. 展开更多
关键词 synthesis crystal structure copper (Ⅱ) complex 1 10-phenanthroline-5 6-dione
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Synthesis and Crystal Structure of 1,4-Bis(2-hydroxymethylphenyl)-1,4-dioxabutane
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作者 许兴友 刘清亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期473-476,共4页
A new ligand 1,4-bis(2-hydroxymethylphenyl)-1,4-dioxabutane was synthesized by reducing 1,4-bis(2-formylphenyl)-1,4-dioxabutane with NaBH4 in absolute methanol solution. The crystal structure of the title compound C16... A new ligand 1,4-bis(2-hydroxymethylphenyl)-1,4-dioxabutane was synthesized by reducing 1,4-bis(2-formylphenyl)-1,4-dioxabutane with NaBH4 in absolute methanol solution. The crystal structure of the title compound C16H18O4 has been determined by single-crystal X-ray diffraction. The ligand crystallizes in the orthorhombic system, space group Pbcn with a = 13.777(1), b = 11.731(1), c = 9.076(8) ? V = 1466.8(2) ?, Mr = 274.30, Z = 4, F(000) = 548, Dc = 1.24 g/cm3, T = 293 K, m = 8.9 cm-1 and l = 0.71073 ? The structure was refined to R = 0.0324 and wR = 0.1025 for 1112 observed reflections with I > 2s(I). The two benzene rings are not on the same plane, and the dihedral angle between them is 60.6? The ligand has C2 symmetry axis which passes through the center of C(8)C(8a). The molecules are linked to each other by hydrogen bonding network to form supramolecular chain. The ligands connect to each other through the hydrogen bonds to form one-dimensional chains which further connect through the hydrogen bonds to form two- and three-dimensional structures. 展开更多
关键词 LIGAND SYNTHESIS crystal structure
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One-dimensional Zigzag Chain Coordination Polymer [Zn(μ-phth)(imi)_2]_∞ Bridged by ο-Phthalato 被引量:1
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作者 刘庆燕 刘平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期509-512,共4页
The reaction of zinc carbonate with o-phthalic acid and imidazole in an aqueous-alcohol solution led to the formation of colorless crystals of [Zn(-phth)(imi)2]∞. Single-crystal X-ray analysis has revealed that the c... The reaction of zinc carbonate with o-phthalic acid and imidazole in an aqueous-alcohol solution led to the formation of colorless crystals of [Zn(-phth)(imi)2]∞. Single-crystal X-ray analysis has revealed that the complex crystallizes in a monoclinic system, space group Pn with a = 8.394(2), b = 9.976(3), c = 9.959(3) ? ?= 104.409(4)? V = 807.6(4) ?, Z = 2, C14H12N4O4Zn, Mr = 365.65, Dc = 1.504 g/cm3, ?= 1.544 mm-1, F(000) = 372, the final R = 0.0466 and wR = 0.1171 for 1834 reflections with I >2(I). The complex displays a zigzag infinite chain structure in which each zinc (Ⅱ) center is coordinated by two oxygen atoms and two nitrogen atoms to generate a ZnN2O2 distorted tetrahedral geometry. The neighboring zinc atoms are bridged by the o-phthalate ligand. Each chain is linked by hydrogen bonds with its neighbors to form a three-dimensional coordination polymer. 展开更多
关键词 zinc (Ⅱ) complex o-phthalate crystal structure chain coordination polymer
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Two New Inclusion 1,4-Butylenediphosphonates with 3D Hydrogen-bonded Frameworks
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作者 傅瑞标 吴新涛 +2 位作者 胡胜民 杜文新 张建军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第8期855-861,共7页
Two new inclusion 1,4-butylenediphosphonates with three-dimensional hydrogen- bonded frameworks have been synthesized and determined by single-crystal X-ray diffraction. In compound 1, the two-dimensional cationic sub... Two new inclusion 1,4-butylenediphosphonates with three-dimensional hydrogen- bonded frameworks have been synthesized and determined by single-crystal X-ray diffraction. In compound 1, the two-dimensional cationic substructures interpenetrate into the anionic framework, and in compound 2, the cations are encapsulated in the three-dimensional framework. Crystal 1 (C14H24N2O8P2) belongs to triclinic, space group P?with a = 9.4645(2), b = 9.6490(2), c = 11.9479(3) ? = 79.7420(10), b = 73.5650(10), = 63.8420(10), V = 937.55(4) 3, Z = 2, Mr = 410.29, Dc = 1.453 g/cm3, m(MoKa) = 0.276 mm-1, F(000) = 432, the final R = 0.0465 and wR = 0.1304 for 3274 independent reflections. Crystal 2 (C18H26N2O10P2) is of monoclinic, space group P21/c with a = 9.7069(12), b = 16.227(2), c = 6.9339(9) ? b = 98.834(3), V = 1079.2(2) ?, Z = 2, Mr = 492.35, Dc = 1.515 g/cm3, m(MoKa) = 0.261 mm-1, F(000) = 516, the final R = 0.0611 and wR = 0.1162 for 1871 independent reflections. 展开更多
关键词 crystal structure 1 4-butylenediphosphonates hydrogen-bonded frameworks
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Crystal structures and theoretical investigation of anti-/syn-2,4-diphenylpentane-and 2,4-di-p-tolylpentane-2,4-diols
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作者 焦银春 曹晨忠 赵小林 《Journal of Central South University》 SCIE EI CAS 2012年第5期1219-1225,共7页
2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols were investigated employing experimental and density functional theory (DFT) method at B3LYP/6-31G (d) level. The structure of syn-2,4-di-p-tolylpentane-2,4... 2,4-diphenylpentane- and 2,4-di-p-tolylpentane-2,4-diols were investigated employing experimental and density functional theory (DFT) method at B3LYP/6-31G (d) level. The structure of syn-2,4-di-p-tolylpentane-2,4-diol (2b) was characterized by X-ray diffraction and compared with the crystal structures of anti- and syn-2,4-diphenylpentane-2,4-diols (la and lb). X-ray diffraction indicates that inter and intra-molecular hydrogen bonds are formed in the crystal structures. There is n-n staking interaction in lb and 2b. Good linear correlations and similar results are found between the experimental 1H and 13C NMR chemical shifts (6~exp) and GIAO (Gauge Independent Atomic Orbital) method calculated magnetic isotropic shielding tensors (acalc). HOMO and LUMO molecular orbitals were calculated at the same levels with the different results. UV-vis absorption spectra of the compounds were recorded in EtOH, MeCN, n-BuOH and cyclohexane with different dielectric constants. It is found that the solvent effect is obvious when e is 24.85(EtOH), 35.69(MeCN) and it is weak when e is decreased to 17.33(n-BuOH), 1.18 (cyclohexane). 展开更多
关键词 x-ray crystallography hydrogen bonds nuclear magnetic resonance (NMR) density function theory (DFT) UV-visabsorption solvent effect
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