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81.
Ana María Atria Maria Teresa Garland Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(7):m185-m188
The title ionic compound, (C7H8N3)2[Ho2(C4H5O2)8], is constructed from two almost identical independent centrosymmetric anionic dimers balanced by two independent 2‐amino‐1H‐benzimidazol‐3‐ium (Habim+) cations. The asymmetric part of each dimer is made up of one HoIII cation and four crotonate (crot or but‐2‐enoate) anions, two of them acting in a simple η2‐chelating mode and the remaining two acting in two different μ2:η2 fashions, viz. purely bridging and bridging–chelating. Symmetry‐related HoIII cations are linked by two Ho—O—Ho and two Ho—O—C—O—Ho bridges which lead to rather short intracationic Ho...Ho distances [3.8418 (3) and 3.8246 (3) Å]. In addition to the obvious Coulombic interactions linking the cations and anions, the isolated [Ho2(crot)8]2− and Habim+ ions are linked by a number of N—H...O hydrogen bonds, in which all N—H groups of the cation are involved as donors and all (simple chelating) crot O atoms are involved as acceptors. These interactions result in compact two‐dimensional structures parallel to (110), which are linked to each other by weaker π–π contacts between Habim+ benzene groups. 相似文献
82.
Sebastin Suarez Fabio Doctorovich Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(10):o417-o420
The title compound, C21H21NO7S3, consists of an SO2ON(SO2)2 central fragment and three terminal 4‐methylphenyl groups each attached at a sulfonyl S atom. The most obvious characteristic is the presence of two nearly face‐to‐face benzene rings, with their centroids separated by a rather short distance [3.7808 (18) Å], but with a rather slanted relative orientation [dihedral angle = 20.63 (13)°] so as to preclude a strong intramolecular π–π interaction. The third benzene ring is nearly perpendicular to the other two [dihedral angles = 71.62 (14) and 70.4 (13)°]. The packing of the structure is directed by two C—H...O hydrogen bonds involving aromatic H atoms (methyl H atoms are strictly non‐interacting), which define chains running in the [100] direction. These one‐dimensional chains evolve parallel to each other and exhibit no significant lateral interactions. 相似文献
83.
Mariana Dennehy Eleonora Freire Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(1):m17-m20
The triclinic structure of the title compound, cyclo‐tetrakis(μ‐1,1‐dioxo‐1λ6,2‐benzothiazole‐3‐thiolato‐κ2S:S)tetrakis[(triphenylphosphane‐κP)silver(I)], [Ag4(C7H4NO2S2)4(C18H15P)4], is a polymorph of the previously reported monoclinic structure [Dennehy, Mandolesi, Quinzani & Jennings (2007). Z. Anorg. Allg. Chem. 633 , 2746–2752]. In both polymorphs, the complex lies on a crystallographic inversion centre and the bond distances are closely comparable. Some differences can be found in the interatomic angles and torsion angles involving the inner Ag4S4 skeleton. The polymorphs contain essentially identical two‐dimensional layers, but with different layer stacking arrangements. In the triclinic form, all layers are related by lattice translation, while in the monoclinic form they are arranged around glide planes so that adjacent layers are mirrored with respect to each other. 相似文献
84.
M. Enriqueta Díaz de Vivar Sergio Baggio Juan Carlos Muoz Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):m30-m33
Two different zinc sulfite compounds have been prepared through the decomposition of pyrosulfite–dithionite ions in aqueous solution, viz. a dimeric complex, di‐μ‐sulfito‐κ3O,O′:O′′;κ3O:O′,O′′‐bis[(4,4′‐dimethyl‐2,2′‐bipyridine‐κ2N,N′)zinc(II)] dihydrate, [Zn2(SO3)2(C12H12N2)2]·2H2O, (I), which was solved and refined from a twinned sample, and an extended polymer, poly[[aqua(1,10‐phenanthroline‐κ2N,N′)zinc(II)]‐μ3‐sulfito‐κ2O:O′:O′′‐zinc(II)‐μ3‐sulfito‐κ3O:O:O′], [Zn2(SO3)2(C12H10N2)(H2O)]n, (II). In (I), the dinuclear ZnII complex has a center of symmetry. The cation is five‐coordinate in a square‐pyramidal arrangement, the anion fulfilling a bridging chelating role. Compound (II) comprises two different zinc units, one being five‐coordinate (square pyramidal) and the other four‐coordinate (trigonal pyramidal), and two independent sulfite groups with different binding modes to the cationic centers. 相似文献
85.
Fredy R. Prez Julio Belmar Claudio Jimnez Yanko Moreno Patricio Hermosilla Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):m318-m320
The title compound, [Cu(C19H26N3O)2], is the first reported complex of the alkylpyrazolone‐derived ligand 1‐n‐hexyl‐3‐methyl‐4‐[1‐(phenylimino)propyl]‐1H‐pyrazol‐5(4H)‐one. The most notable feature is the imine–enol character presented by the ligand due to coordination, in spite of its enamine–ketone structure in the free state. The ligand chelates through N and O atoms, resulting in a square‐planar coordination around the CuII atom, which lies on an inversion centre. 相似文献
86.
Ricardo Baggio Nieves M. C. Casado Rafael Calvo Raul E. Rapp María Teresa Garland 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):m250-m252
In the title compound, [Cu(C15H20N2O4)]n, the copper(II) coordination is square planar. The anionic l ‐tyrosyl‐l ‐leucinate ligand binds in an N,N′,O‐tridentate mode to one CuII cation on one side and in an O‐monodentate mode to a second CuII cation on the other side, thus defining –Cu—O—C—O—Cu′– chains which run along the a axis. These chains are held together by a strong hydrogen bond involving the hydroxy H atom. 相似文献
87.
Juan Granifo María Teresa Garland Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):m97-m100
The structure of the title compound, catena‐poly[[bis(1,1,1,5,5,5‐hexafluoropentane‐2,4‐dionato‐κ2O,O′)zinc(III)]‐μ‐4,4′‐bipyridine‐κ2N:N′], [Zn(C5HF6O2)2(C10H8N2)]n, consists of polymeric chains, running in two perpendicular directions, organized as planes normal to the tetragonal axis. The elemental unit of the chains is the zinc(II) coordination polyhedron bisected by a twofold symmetry axis, and thus only half of the unit is independent. The octahedral coordination geometry of the metal centre is composed of two oxygen‐chelating (symmetry‐related) hexafluoroacetylacetonate groups and two translationally related 4,4′‐bipyridine groups, which act as connecting agents in the polymer structure. The stabilization of this architecture of chains and planes is associated with a number of weak C—H⋯O and C—H⋯F hydrogen bonds. 相似文献
88.
Juan Granifo Rubn Gavio Sebastin Surez Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(9):1299-1309
The structures of a new hybrid terpyridine–pyrazine ligand, namely 4′‐[4‐(pyrazin‐2‐yl)phenyl]‐4,2′:6′,4′′‐terpyridine (L2), C25H17N5, and its one‐dimensional coordination polymer catena‐poly[[bis(acetylacetonato‐κ2O,O′)zinc]‐μ‐4′‐[4‐(pyrazin‐2‐yl‐κN4)phenyl]‐4,2′:6′,4′′‐terpyridine‐κN1], [Zn(C5H7O2)2(C25H17N5)]n or [Zn(acac)2(L2)]n (Hacac is acetylacetone), are reported. Packing interactions in both crystal structures are analyzed using Hirshfeld surface and enrichment ratio techniques. For the simpler structure of the monomeric ligand, further studies on the interaction hierarchy using the energy framework approach were made. The result was a complete picture of the intermolecular interaction landscape, which revealed some subtle details, for example, that some weak (at first sight negligible) C—H…N interactions in the structure of free L2 play a relevant role in the crystal stabilization. 相似文献
89.
Cristian Paz Robles Viviana Burgos Sebastin Suarez Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(11):1007-1010
The natural compound dendocarbin A, C15H22O3, is a sesquiterpene lactone isolated for the first time from Drimys winteri for var chilensis. The compound crystallizes in the orthorhombic space group P212121 and its X‐ray crystal structure confirmed the S/R character of the chiral centres at C‐5/C‐10 and C‐9/C‐11, respectively. The α‐OH group at C‐11 was found to be involved in intermolecular hydrogen bonding, defining chains along the <100> 21 screw axis. 相似文献
90.