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Dr. Zhifang Guo Dr. Victoria L. Blair Prof. Glen B. Deacon Prof. Peter C. Junk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(3):e202103865
Unique outcomes have emerged from the redox transmetallation/ protolysis (RTP) reactions of europium metal with [Ag(C6F5)(py)] (py=pyridine) and pyrazoles (RR′pzH). In pyridine, a solvent not normally used for RTP reactions, the products were mainly EuII complexes, [Eu(RR′pz)2(py)4] (RR′pz=3,5-diphenylpyrazolate (Ph2pz) 1 ; 3-(2-thienyl)-5-trifluoromethylpyrazolate (ttfpz) 2 ; 3-methyl-5-phenylpyrazolate (PhMepz) 3 ). However, use of 3,5-di-tert-butylpyrazole (tBu2pzH) gave trivalent [Eu(tBu2pz)3(py)2] 4 , whereas the bulkier N,N′-bis(2,6-difluorophenyl)formamidine (DFFormH) gave divalent [Eu(DFForm)2(py)3] 5 . In tetrahydrofuran (thf), the usual solvent for RTP reactions, C−F activation was observed for the first time with [Ag(C6F5)(py)] in such reactions. Thus trivalent [{Eu2(Ph2pz)4(py)4(thf)2(μ-F)2}{Eu2(Ph2pz)4(py)2(thf)4(μ-F)2}] ( 6 ), [Eu2(ttfpz)4(py)2(dme)2(μ-F)2] ( 7 ), [Eu2(tBu2pz)4(dme)2(μ-F)2] ( 8 ) were obtained from the appropriate pyrazoles, the last two after crystallization from 1,2-dimethoxyethane (dme). Surprisingly 3,5-dimethylpyrazole (Me2pzH) gave the divalent cage [Eu6(Me2pz)10(thf)6(μ-F)2] ( 9 ). This has a compact ovoid core held together by bridging fluoride, thf, and pyrazolate ligands, the last including the rare μ4-1η5(N2C3): 2η2(N,N′): 3κ(N): 4κ(N′) pyrazolate binding mode. With the bulky N,N′-bis(2,6-diisopropylphenyl)formamidine (DippFormH), which often favours C−F activation in RTP reactions, neither oxidation to EuIII nor C−F activation was observed and [Eu(DippForm)2(thf)2] ( 10 ) was isolated. By contrast, Eu reacted with Bi(C6F5)3 and Ph2pzH or tBu2pzH in thf without C−F activation, to give [Eu(Ph2pz)2(thf)4] ( 11 ) and [Eu(tBu2pz)3(thf)2] ( 12 ) respectively, the oxidation state outcomes corresponding to that for use of [Ag(C6F5)(py)] in pyridine. 相似文献
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Glen B. Deacon Ewan E. Delbridge Craig M. Forsyth 《Angewandte Chemie (International ed. in English)》1999,38(12):1766-1767
A linear supramoleculecular array of anions and cations is present in the solvent-free potassium salt of the homoleptic erbium pyrazolate complex [K{Er(η2-tBu2pz)4}n] ( 1 ). Treatment of 1 with [18]crown-6 in toluene/dimethoxyethane leads to formation of a charge-separated salt [Eq. (a)] in which the methyl group of a toluene molecule interacts with the potassium ion. tBu2pz=3,5-di-tert-butylpyrazolate. 相似文献
156.
Glen B. Deacon Craig M. Forsyth Dominique M. M. Freckmann Dominique M. M. Freckmann Gerd Meyer Dirk Stellfeldt 《无机化学与普通化学杂志》2000,626(2):540-546
The X‐ray crystal structures of Hg(C6F4X‐p)2 (X = NH2, OMe, or Me) show the compounds to have almost linear C–Hg–C stereochemistry (X = NH2, 176.3(4)°; X = OMe, 179.5(2)°; X = Me, 176.3(2)°), and the two tetrafluoroaryl rings rotated ca. 52–62° with respect to each other. Substantial conjugation of NH2 and OMe groups with the aromatic rings is evident from N–C and O–C(Ar) distances. For X = NH2 or OMe, two weak N(O)–Hg coordination interactions per mercury lead to a two dimensional supramolecular chain structure containing pairs of π‐stacked aromatic rings at near van der Waals contact distances rotated at 62.2° (X = NH2) or 52.9° (X = OMe) to each other. In Hg(C6F4Me‐p)2, which does not have potential donor atoms, no supramolecular structure is obtained, the molecules being laterally displaced from one another. 相似文献
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Chesman AS Turner DR Izgorodina EI Batten SR Deacon GB 《Dalton transactions (Cambridge, England : 2003)》2007,(14):1371-1373
The complexes [Et(4)N](3)[Ln(eta(2)-dcnm)(6)] (Ln = La, Ce, Nd, Gd, dcnm = dicyanonitrosomethanide) have discrete N, O 12-coordination owing to symmetrical chelation of the nitroso donor groups. 相似文献