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101.
Laura Cañadillas‐Delgado Dr. Tomás Martín Dr. Oscar Fabelo Dr. Jorge Pasán Dr. Fernando S. Delgado Dr. Francesc Lloret Prof. Dr. Miguel Julve Prof. Dr. Catalina Ruiz‐Pérez Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(13):4037-4047
The preparation, X‐ray crystallography and magnetic investigation of the first examples of methanetriacetate (mta)‐containing lanthanide(III) complexes of formulae [Gd(mta)(H2O)3]n ? 4 n H2O ( 1 ) [Gd(mta)(H2O)3]n ? 2 n H2O ( 2 ) and [Gd2(mta)2(H2O)2]n ? 2 n H2O ( 3 ) are described herein. This tripodal ligand promotes the formation of 63 networks; thus 1 consists of a honeycomb structure, whereas in 2 two of these layers are condensed to form a rare five‐connected two‐dimensional (4862) network. Compound 3 can be seen as an aggregation of 63 layers leading to a three‐dimensional (6,6)‐connected binodal (41263)(4966)‐ nia net, in which the gadolinium(III) ions and the mta ligands act as octahedral and as trigonal prismatic nodes, respectively. The magnetic properties of 1 – 3 were investigated in the temperature range 1.9–300 K. A close fit to the Curie law ( 1 ) and weak either antiferro‐ [J=?0.0063(1) cm?1 ( 2 )] or ferromagnetic [J=+0.0264(6) cm?1 ( 3 )] interactions between the GdIII ions are observed; the different exchange pathways involved [extended tris‐bidentate mta ( 1 ) and μ‐O(1);κ2O(1),O(2) ( 2 and 3 ) plus single syn–syn carboxylate‐mta ( 3 )] accounting for these magnetic features. The nature and magnitude of the magnetic interactions, between the GdIII ions in 1 – 3 , agree with the small amount of data existing in the literature for these kind of bridges. 相似文献
102.
Dr. Emilio Pardo Jesús Ferrando‐Soria Dr. Marie‐Claire Dul Dr. Rodrigue Lescouëzec Dr. Yves Journaux Dr. Rafael Ruiz‐García Dr. Joan Cano Prof. Dr. Miguel Julve Prof. Dr. Francesc Lloret Dr. Laura Cañadillas‐Delgado Dr. Jorge Pasán Prof. Dr. Catalina Ruiz‐Pérez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(43):12762-12762
103.
Martínez-Lillo J Delgado FS Ruiz-Pérez C Lloret F Julve M Faus J 《Inorganic chemistry》2007,46(9):3523-3530
The use of the (NBu4)2[ReIVCl4(ox)] mononuclear species as a ligand toward divalent first row transition metal ions in the presence of imidazole affords the new trinuclear compounds of formula (NBu4)2[{ReIVCl4(mu-ox)}2MII(Him)2] [NBu4+=tetra-n-butylammonium cation, ox=oxalate dianion, Him=imidazole; M=Mn (1), Co (2), Ni (3), Cu (4)] whose preparation, crystal structures, and magnetic properties are reported. 1-4 are isostructural complexes which are made up of discrete trinuclear [{ReIVCl4(mu-ox)}2MII(Him)2]2- anions and bulky NBu4+ cations. The Re and M atoms exhibit somewhat distorted octahedral surroundings which are built by four chloro and two oxalate oxygens (Re) and two imidazole nitrogen and four oxalate oxygen atoms (M), the central M atom being linked to the two peripheral Re atoms through bis-bidentate oxalate. The values of the Re...M separation across bridging oxalate vary in the range 5.646(2) (M=Ni) to 5.794(2) A (M=Mn). Magnetic susceptibility measurements on polycrystalline samples of 1-4 in the temperature range 1.9-300 K show the occurrence of significant intramolecular antiferro- (1) and ferromagnetic (2-4) interactions. The nature and magnitude of the magnetic coupling in 1-4 are qualitatively understood through orbital symmetry considerations. 相似文献
104.
Isabel Castro Juan Faus Miguel Julve Michèle Philoche-Levisalles 《Transition Metal Chemistry》1992,17(3):263-269
Two complexes of formula [Cu(terpy)(H2O)](CF3SO3)2 (1) and [Cu(terpy)(OH)]BPh4 (2) (terpy=2,2′∶6′,2″-terpyridine and BPh4=tetraphenylborate anion) have been synthesized and characterized by spectroscopic techniques. The x-ray crystal structure
of (1) has been determined by x-ray diffraction. The structure is made up of [Cu(terpy)(H2O)]2+ mononuclear cations plus semi-coordinated CF3SO3
− anions. The coordination geometry around the copper atom is approximately elongated tetragonal octahedral. The oxygen atom
of water and the three nitrogen atoms of terpy occupy the equatorial sites whereas the apical ones are filled by trifluoromethanesulphonate
oxygen atoms. The formation of hydroxo complexes of [Cu(terpy)(H2O)]2+ has been investigated by potentiometry in aqueous solutions and the constants of the Equilibria (1) and (2)
相似文献
105.
Armentano D Mastropietro TF De Munno G Rossi P Lloret F Julve M 《Inorganic chemistry》2008,47(9):3772-3786
A series of oxalate-bridged iron(III) complexes have been synthesized by the reaction of FeCl 3 with oxalic acid (H 2ox) and XCl, where X is a substituted univalent ammonium or an alkaline cation. We have obtained basically two different types of compounds by varying the nature and the shape of the counterion, with the dimensionality of the resulting product being strongly influenced by the counterion. Three-dimensional (3D) networks of oxo- and oxalato-bridged iron(III) ions of the general formula {X 2[Fe 2O(ox) 2Cl 2]. pH 2O} n have been obtained for X = Li (+) ( 1), Na (+) ( 2), and K (+) ( 3) with p = 4 and X = MeNH 3 (+) ( 4), Me 2NH 2 (+) ( 5), and EtNH 3 (+) ( 6) with p = 2. Similar 3D hydroxo- and oxalato-bridged iron(III) networks of the formula {X[Fe 2(OH)(ox) 2Cl 2].2H 2O} n resulted for X = EtNH 3 (+) ( 7a) and PrNH 3 (+) ( 8). Compound 7a undergoes a solid-to-solid transformation, leading to a new species of the formula {(H 3O)(EtNH 3)[Fe 2O(ox) 2Cl 2].H 2O} n ( 7b). Chainlike compounds of the formula {X 2[Fe 2(ox) 2Cl 4]. pH 2O} n [X = Me 2NH 2 (+)( 9, p = 1), Me 3NH (+) ( 10, p = 2), and Me 4N (+) ( 11, p = 0)] have been obtained for the bulkier alkylammonium cations. Magnetic susceptibility measurements in the temperature range 1.9-295 K show the occurrence of weak ferromagnetic ordering due to spin canting in the 3D networks 1- 8, with the value of the critical temperature ( T c) varying with the cation in the range 26 K ( 2) to 70 K ( 8) without significant structural modifications. The last three one-dimensional compounds exhibit the typical behavior of antiferromagnetically coupled chains of interacting spin sextets [ J = -8.3 ( 9), -6.9 ( 10), and -8.4 ( 11) cm (-1) with H = - J summation operator i S i S i+1 ]. 相似文献
106.
Vallejo J Cano J Castro I Julve M Lloret F Fabelo O Cañadillas-Delgado L Pardo E 《Chemical communications (Cambridge, England)》2012,48(62):7726-7728
The coordination chemistry of the 2,3-quinoxalinediolate ligand with different lanthanide(III) ions in basic media in air affords a new family of carbonato-bridged M(2)(III) compounds (M = Pr, Gd and Dy), the Dy(2)(III) analogue exhibiting slow magnetic relaxation behaviour typical of single-molecule magnets. 相似文献
107.
Pardo E Bernot K Julve M Lloret F Cano J Ruiz-García R Delgado FS Ruiz-Pérez C Ottenwaelder X Journaux Y 《Inorganic chemistry》2004,43(9):2768-2770
Two new hexanuclear oxamatocopper(II) complexes 3 and 4 have been synthesized from the binuclear copper(II) complexes of the meta- and para-phenylenebis(oxamate) ligands, respectively. Complexes 3 and 4 possess an overall ladderlike structure made up of two oxamate-bridged linear trinuclear units ("rails") connected through two phenylenediamidate bridges ("rungs") between the central copper atoms to give metallacyclic cores of the meta- and para-cyclophane type, respectively. They show different ground spin states, S = 1 (3) or S = 0 (4), depending on the substitution pattern in the aromatic spacers. The triplet state molecule 3 containing two spin doublet Cu(II)3 units connected by two m-phenylenediamidate bridges represents a successful extension of the concept of "ferromagnetic coupling units" to metal complexes, which is a well-known approach toward high spin organic radicals. 相似文献
108.
Ferrando-Soria J Pasán J Ruiz-Pérez C Journaux Y Julve M Lloret F Cano J Pardo E 《Inorganic chemistry》2011,50(18):8694-8696
Two new heterobimetallic manganese(II)-copper(II) coordination polymers of formulas [Mn(2)Cu(2)(Me(3)mpba)(2)(H(2)O)(6)]·8H(2)O (1) and [Mn(2)Cu(2)(Me(4)ppba)(2)(H(2)O)(6)]·8H(2)O (2) [Me(3)mpba = 2,4,6-trimethyl-N,N'-1,3-phenylenebis(oxamate) and Me(4)ppba = 2,3,5,6-tetramethyl-N,N'-1,4-phenylenebis(oxamate)] have been synthesized following a molecular-programmed self-assembly method from the corresponding dicopper(II) complexes acting as metalloligands toward Mn(II) ions. 1 and 2 consist of neutral Mn(II)(2)Cu(II)(2) layers with a brick-wall structure made up of oxamato-bridged Mn(II)Cu(II) chains connected through double meta- (1) and para-substituted (2) permethylated phenylene spacers. Overall magnetic (1) and nonmagnetic (2) layer ground states result from the ferro- and antiferromagnetic interchain interactions between the oxamato-bridged Mn(II)Cu(II) ferrimagnetic chains across m- and p-phenylene spacers, respectively. Interestingly, compound 1 exhibits a long-range ferromagnetic ordering with a rather high Curie temperature (T(C)) of 20.0 K. 相似文献
109.
Martínez-Lillo J Mastropietro TF De Munno G Lloret F Julve M Faus J 《Inorganic chemistry》2011,50(12):5731-5739
Four heterotrinuclear Re(IV)(2)M(II) compounds of general formula (NBu(4))(2)[{Re(IV)Br(4)(μ-ox)}(2)M(II)(Him)(2)] [NBu(4)(+) = tetra-n-butylammonium cation, ox = oxalate, Him = imidazole; M = Mn (1), Co (2), Ni (3), and Cu (4)] have been synthesized by using the novel mononuclear complex [Re(IV)Br(4)(ox)](2-) as a ligand toward divalent first-row transition metal ions in the presence of imidazole. Compounds 1-4 are isostructural complexes whose structure contains discrete trinuclear [{Re(IV)Br(4)(μ-ox)}(2)M(II)(Him)(2)](2-) anions and bulky NBu(4)(+) cations. The Re and M atoms are six-coordinated: four peripheral bromo and two oxalate-oxygens (at Re), and two cis-coordinated imidazole molecules and four oxygen atoms from two oxalate ligands (at M), build distorted octahedral surroundings. Two peripheral [ReBr(4)(ox)](2-) units act as bidentate ligands through the oxalate group toward the central [M(II)(Him)(2)] fragment affording the trinuclear entities. The values of the intramolecular Re···M separation are 5.62(1) (1), 5.51(1) (2), 5.46(1) (3), and 5.55(1) ? (4). Magnetic susceptibility measurements on polycrystalline samples of 1-4 in the temperature range of 1.9-300 K show the occurrence of intramolecular antiferro- [J = -1.1 cm(-1) (1)] and ferromagnetic interactions [J = +3.9 (2), +19.7 (3), and +14.4 cm(-1) (4)], the Hamiltonian being defined as H? = -J [S?(M)(S?(Re1) + S?(Re2))]. The larger spin delocalization on the oxalato bridge in 1-4 when compared to the trinuclear Re(IV)(2)M(II) complexes with chloro instead of bromo as peripheral ligands (1'-4') accounts for the strengthening of the magnetic interactions in 1-4 [J = -0.35 (1'), +14.2 (3'), and +7.7 cm(-1) (4')]. An incipient frequency dependence of the out-of-phase ac signals of 3 at very low temperatures is reminiscent of a system with slow relaxation of the magnetization, a phenomenon characteristic of single-molecule magnet behavior. 相似文献
110.
Rafael Ruiz Miguel Julve Juan Cano Juan Soto Ramón Martínez-Máñez Carmen Muñoz Jorgel Payá 《Transition Metal Chemistry》1993,18(5):523-527
Summary A series of complexes of formula {Ni(Me6[14]aneN4)X2| (Me6[14]aneN4) = C-meso-5,5,7,12,12,14-hexamethyl-1,4,-8,11-tetraazacyclotetradecane and X = N3
(1), NCO (2), NCS (3), AcO (4) or I (5) has been synthesized. The crystal structure of (5) has been determined by X-ray diffraction methods. The nickel atom is surrounded by a square-planar array of nitrogen atoms, giving a low-spin complex. The macrocyclic ligand shows the most stable conformation, the six-membered rings exhibiting the chair form while the gauche conformation is adopted by the five-membered rings. Spectroscopic and magnetic data for (1)–(4) are consistent with octahedral coordination around the nickel atom, which is achieved by four N atoms of the macrocyclic ligand in a single plane and by two azido-N (1), cyanato-N (2), thiocyanato-N (3) and carboxylato-O (4) groups occupying the axial positions. An electrochemical study of the oxidation of (1)–(5) has been carried out in nonaqueous solvents and the prospects of synthesis of the corresponding nickel(III) species are discussed in the light of the electrochemical data. 相似文献