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71.
72.
An unusual 3D coordination polymer based on bridging interactions of the nucleobase adenine 总被引:1,自引:0,他引:1
García-Terán JP Castillo O Luque A García-Couceiro U Román P Lezama L 《Inorganic chemistry》2004,43(15):4549-4551
The first 3D coordination polymer containing a nucleobase as a bridging ligand, [[Cu2(mu-ade)4(H2O)2][Cu(ox)(H2O)]2 x approximately 14H2O]n (1), has been synthesized by reaction of adenine (Hade) with a basic solution of K2[Cu(ox)2] x 2H2O (ox = oxalato dianion). Compound 1 crystallizes in the trigonal space group R3 with a = b = 31.350(1) angstroms, c = 14.285(1) angstroms, V = 12158.7(10) angstroms3, and Z = 9. X-ray analysis shows a covalent 3D network in which the copper(II) centers are bridged by tridentate mu-N3,N7,N9 adeninate ligands. The compound has relatively large, nanometer-sized tubes associated with the self-assembly process directed solely by metal-ligand interactions. The covalent 3D framework remains intact upon removal of the guest water molecules trapped in the nanotubes. Magnetic measurements indicate an overall antiferromagnetic behavior of the compound. 相似文献
73.
Serna ZE Urtiaga MK Barandika MG Cortés R Martin S Lezama L Arriortua MI Rojo T 《Inorganic chemistry》2001,40(18):4550-4555
Three tetrameric cobalt(II)-pseudohalide complexes have been structurally and magnetically characterized. Compounds 1 and 2 are isomorphous and exhibit the general formula [Co2(dpk-OH)(dpk-CH3O)(L)(H2O)]2A2-4H2O where dpk = di-2-pyridyl ketone, L = N3(-) and A = BF4(-) for 1, and L = NCO(-) and A = ClO4(-) for 2. The ligands dpk-OH(-) and dpk-CH3O(-) result from solvolysis and ulterior deprotonation of dpk in water and methanol, respectively. Both compounds exhibit cationic tetramers consisting of a dicubane-like core with two missing vertexes where the Co(II) ions are connected through end-on pseudohalide and oxo-bridges. A similar tetranuclear core has been found for 3 whose formula is [Co2(dpk-OH)(dpk-CH3O)(NCO)2]2. In this case, the tetramers are neutral and exhibit a terminal cyanate in place of the coordinated molecule of water for 1 and 2. The tetrameric units for 2 and 3 represent the first examples of any kind of cubanes exhibiting cyanate bridges as well as the first Co(II) compounds exhibiting intermetallic bridges through these pseudohalide groups. Measurements of the magnetic susceptibility indicated the presence of ferromagnetic Co(II)-Co(II) interactions in the three compounds. 相似文献
74.
Martín S Barandika MG Lezama L Pizarro JL Serna ZE Ruiz De Larramendi JI Arriortua MI Rojo T Cortés R 《Inorganic chemistry》2001,40(17):4109-4115
Four compounds of general formula [M(4,4'bipy)(N(3))2](n) (M = Mn (1), Zn (2), Co (3), Ni (4)) have been synthesized and magnetostructurally characterized by means of X-ray diffraction analysis, IR and ESR spectroscopies, and measurements of the magnetic susceptibility and magnetization. Compound 1 (C(10)H(8)N(8)Mn) crystallizes in the tetragonal P4(3)2(1)2 space group, Z = 4, with a = 8.229(2), b = 8.229(2), and c = 16.915(2) A. It exhibits an acentric 3D structure where Mn(II) ions are linked through EE-azide groups resulting in a diamondoid network. The 4,4'bipy ligands are coordinated on the axial positions of the octahedral spheres reinforcing the intermetallic connections. Weak ferromagnetism arising from spin canting is observed for compound 1. Compounds 2, 3, and 4 are proposed to be isomorphous and would consist of a 2D array where alternating EO + EE/EO + EE/EO + EO azide-chains are linked by 4,4'bipy ligands resulting in pi-pi stacked pyridyl-columns. The azido ligand dispositions in compounds 3 and 4 make possible systems of type -AF-AF-F-, which would give rise to a topological ferromagnetic behavior. 相似文献
75.
San Felices L Vitoria P Gutiérrez-Zorrilla JM Reinoso S Etxebarria J Lezama L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(20):5138-5146
Reaction of monosubstituted Keggin polyoxometalates (POMs) and [Cu(ac)(pmdien)]+ generated in situ led to the formation of the hybrid metal organic-inorganic compound K5[Cu(ac)(pmdien)][SiW11CuO39].12H2O; its crystal structure and magnetic properties have also been determined. The packing of this compound can be viewed as a stacking of hydrogen-bonded chiral double chains, with the cationic complexes located between the two-dimensional arrangement of POM double chains. DFT calculations performed on [Cu(ac)(pmdien)]+ suggest that the distortion presented in this cationic copper complex is due to electronic effects. An AIM stability study of the cationic copper complex, in order to determine the relationship between the bond angle Cu-O-C and the denticity of the acetate ligand, has been carried out. Topological analyses over the polyhedral distortion, both of the monosubstituted polyanion and copper complexes, have been performed by means of continuous shape measures (CSM). 相似文献
76.
Serna ZE Lezama L Urtiaga MK Arriortua MI Barandika MG Cortés R Rojo T 《Angewandte Chemie (International ed. in English)》2000,39(2):344-347
A combination of azido and dipyridylketone (dpk) ligands led to the isolation of the tetranuclear Ni(II) complex 1 (dpkOH and dpkOCH(3) result from solvolysis of dpk). The complex exhibits ferromagnetic behavior, and its structure can be described as a dicubane unit with two missing vertices (see picture). 相似文献
77.
Caballero AB Rodríguez-Diéguez A Lezama L Barea E Salas JM 《Dalton transactions (Cambridge, England : 2003)》2011,40(19):5180-5187
Conventional reactions of the versatile multidentate ligand 5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one (HmtpO) with metallic(II) salts lead to three novel multidimensional complexes [Cu(HmtpO)(2)(H(2)O)(3)](ClO(4))(2)·H(2)O (1), {[Cu(HmtpO)(2)(H(2)O)(2)](ClO(4))(2)·2HmtpO}(n) (2) and {[Co(HmtpO)(H(2)O)(3)](ClO(4))(2)·2H(2)O}(n) (3). In each compound, the triazolopyrimidine ligand shows a different and unusual coordination mode, giving rise to structures with diverse topologies and dimensionality. Compound 1 is a monomeric complex, in which HmtpO shows both N3-monodentate and N1,O71-bidentate modes. 2 is a bidimensional framework with the ligand showing a N3,O71 bidentate-bridging mode. The structure of 3 consists of 1D chains, in which HmtpO displays a N1,N3,O71-tridentate-bridging mode. It should be noted that these coordination modes of the HmtpO ligand are unique in the case of compounds 2 and 3. On the other hand, the magnetic properties of the polynuclear complexes 2 and 3 have been studied showing weak ferromagnetic and antiferromagnetic behaviour, respectively. 相似文献
78.
Abderrahim Guelylah Gotzon Madariaga 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):i32-i34
The structure of Rb2Cd2(SO4)3 at room temperature has been refined using X‐ray diffraction data. The structure is similar to that of other cubic langbeinites. However, the title compound differs from other type I langbeinites in that the bond‐valence sums of the metal cations (in particular the Rb atoms) are practically equal to their nominal chemical valences. 相似文献
79.
Aintzane Goni Luis Lezama Jose Luis Pizarro Jaione Escobal Maria Isabel Arriortua Teofilo Rojo 《ChemInform》1999,30(40):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
80.
Estibaliz Ruiz-Bilbao Dr. Amaia Iturrospe Dr. Santiago Reinoso Dr. Beñat Artetxe Dr. Garikoitz Beobide Dr. Leire San Felices Prof. Luis Lezama Prof. Juan M. Gutiérrez-Zorrilla Dr. Shaza Darwish Dr. Debobroto Sensharma Prof. Michael J. Zaworotko 《Angewandte Chemie (International ed. in English)》2023,62(42):e202307436
The 3D hybrid framework [{Cu(cyclam)}3(κ-Mo8O27)] ⋅ 14H2O ( 1 ) (cyclam=1,4,8,11-tetraazacyclotetradecane) undergoes sequential single-crystal-to-single-crystal transformations upon heating to afford two different anhydrous phases ( 2 a and 3 a ). These transitions modify the framework dimensionality and enable the isomerization of κ-octamolybdate (κ-Mo8) anions into λ ( 2 a ) and μ ( 3 a ) forms through metal migration. Hydration of 3 a involves condensation of one water molecule to the cluster to afford the γ-Mo8 isomer in 4 , which dehydrates back into 3 a through the 6 a intermediate. In contrast, 2 a reversibly hydrates to form 5 , exhibiting the same Mo8 cluster as that of 1 . It is remarkable that three of the Mo8 clusters (κ, λ and μ) are new and that up to three different microporous phases can be isolated from 1 ( 2 a , 3 a , and 6 a ). Water vapor sorption analyses show high recyclability and the highest uptake values for POM-based systems. The isotherms display an abrupt step at low humidity level desirable for humidity control devices or water harvesting in drylands. 相似文献