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41.
Konarev DV Khasanov SS Kovalevsky AY Saito G Otsuka A Lyubovskaya RN 《Dalton transactions (Cambridge, England : 2003)》2006,(30):3716-3720
Single crystals of the ionic C60 complex with bis(benzene)chromium: {Cr(I)(C6H6)2(.+)}.(C60.-)).C6H4Cl2 (1) were obtained. The crystal structure of 1 shows the presence of monomeric C60.- radical anions at 250 K and the formation of single-bonded (C60-)2 dimers at 90 K. The dimerization is realized in two types of the C60.-) pairs with different interfullerene center-to-center distances of 10.052 and 10.279 A arranged in zigzag chains along the a-direction. As a result, two symmetrically independent (C60-)2 dimers found in 1 at 90 K have different environments, intercage C-C bond lengths and C60- center-to-center distances. Such differences should provide different thermal stability of these dimers and result in the appearance of two stages at the dimerization. Indeed, according to SQUID measurements, the magnetic moment of 1 decreases stepwise at the dimerization in two temperature ranges at 240-200 and 200-160 K. 相似文献
42.
Konarev DV Khasanov SS Saito G Vorontsov II Otsuka A Lyubovskaya RN Antipin YM 《Inorganic chemistry》2003,42(12):3706-3708
The C(60) complex with decamethylcobaltocene, (Cp(2)Co)(2)C(60)(C(6)H(4)Cl(2), C(6)H(5)CN)(2) (1) (C(6)H(4)Cl(2) = 1,2-dichlorobenzene; C(6)H(5)CN = benzonitrile), has been obtained as single crystals by the diffusion method. The IR and UV-vis-NIR spectra show the presence of the C(60)(2)(-) and the Cp(2)Co(+) ions, which form a three-dimensional framework with channels accommodating solvent molecules. EPR and SQUID measurements show that C(60)(2)(-) has a diamagnetic singlet (S = 0) state in the 2-140 K range. The appearance of a broad EPR signal and the increase in magnetic susceptibility of 1 above 140 K are assigned to a thermal population of a close lying triplet (S = 1) state. The singlet-triplet energy gap for C(60)(2)(-) in solid 1 is estimated to be 730+/-10 cm(-)(1). 相似文献
43.
O. A. D'yachenko S. V. Konovalikhin G. V. Shilov R. N. Lyubovskaya M. Z. Aldoshina R. B. Lyubovskii 《Russian Chemical Bulletin》1995,44(5):878-882
On the basis of completely deuterated bis(ethylenedithio)tetrathiafulvalene (d8-ET), new organic conductors, (d8-ET)4[Hg2(SCN)4Cl2] and (d8-ET)2[Hg(SCN)2Br] have been synthesized and studied by X-ray structural analysis. Unlike nondeuterated organic metalsk-(ET)2[Hg(SCN)3–n
X
n
] (X = Cl or Br;n=1 and 2), the crystal structure of (d8-ET)4[Hg2(SCN)4Cl4] exhibits -type packing of the d8-ET radical cations in the conducting layer and a polymeric structure of anions, in which both the SCN groups and the Cl atoms are involved in the bridging bonds. The crystals of (d8-ET)2[Hg(SCN)2Br] and the nondeuterated form (ET)2[Hg(SCN)2Br] are isostructural.Translated fromIzvestiya Akademii Nauk. Seriya Khlmicheskaya, No. 5, pp. 905–909, May, 1995.This work was financially supported by the International Science Foundation (Grant RE1 000), the Scientific Council on the Problems of High-Temperature Superconductivity (Project No. 93030), and the Russian Foundation for Basic Research (Project No. 94-03-09950). 相似文献
44.
Konarev DV Khasanov SS Saito G Lyubovskaya RN Yoshida Y Otsuka A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(16):3837-3848
A method for the synthesis of the multicomponent ionic complexes: [Cr(I)(C(6)H(6))(2) (.+)][Co(II)(tpp)(fullerene)(-)].C(6)H(4)Cl(2), comprising bis(benzene)chromium (Cr(C(6)H(6))(2)), cobalt(II) tetraphenylporphyrin (Co(II)(tpp)), fullerenes (C(60), C(60)(CN)(2), and C(70)), and o-dichlorobenzene (C(6)H(4)Cl(2)) has been developed. The monoanionic state of the fullerenes has been proved by optical absorption spectra in the UV/vis/NIR and IR ranges. The crystal structures of the ionic [[Cr(I)(C(6)H(6))(2)](.+)](1.7)[[Co(II)(tpp)(C(60))](2)](1.7-). 3.3 C(6)H(4)Cl(2) and [[Cr(I)(C(6)H(6))(2)] (.+)](2)[Co(II)(tpp)[C(60)(CN)(2)]](-)[C(60)(CN)(2) (.-)]).3 C(6)H(4)Cl(2) are presented. The essentially shortened Co.C(fullerene) bond lengths of 2.28-2.32 A in these complexes indicate the formation of sigma-bonded [Co(II)(tpp)][fullerene](-) anions, which are diamagnetic. All the ionic complexes are semiconductors with room temperature conductivity of 2 x 10(-3)-4 x 10(-6) S cm(-1), and their magnetic susceptibilities show Curie-Weiss behavior. The neutral complexes of Co(II)(tpp) with C(60), C(60)(CN)(2), C(70), and Cr(0)(C(6)H(6))(2), as well as the crystal structures of [Co(II)(tpp)](C(60)).2.5 C(6)H(4)Cl(2), [Co(II)(tpp)](C(70)). 1.3 CHCl(3).0.2 C(6)H(6), and [Cr(0)(C(6)H(6))(2)][Co(II)(tpp)] are discussed. In contrast to the ionic complexes, the neutral ones have essentially longer Co.C(fullerene) bond lengths of 2.69-2.75 A. 相似文献
45.
Konarev DV Khasanov SS Saito G Otsuka A Yoshida Y Lyubovskaya RN 《Journal of the American Chemical Society》2003,125(33):10074-10083
New ionic complexes of fullerenes C(60) and C(70) with decamethylchromocene Cp*(2)Cr.C60.(C(6)H(4)Cl(2))(2) (1), Cp*(2)Cr.C60.(C(6)H(6))(2) (2); the multicomponent complex of (Cs(+))(C70-) with cyclotriveratrylene CTV.(Cs)(2).(C70)(2).(DMF)(7).(C(6)H(6))(0.75) (3); bis(benzene)chromium Cr(C(6)H(6))(2).C60.(C(6)H(4)Cl(2))(0.7) (4), Cr(C(6)H(6))(2).C60.C(6)H(5)CN (5), Cr(C(6)H(6))(2).C70.C(6)H(4)Cl(2) (6), Cr(C(6)H(6))(2).C60 (7); cobaltocene Cp(2)Co.C60.C(6)H(4)Cl(2) (8), Cp(2)Co.C70.(C(6)H(4)Cl(2))(0.5) (9); and cesium Cs.C70.(DMF)(5) (10) have been obtained. The complexes have been characterized by the elemental analysis, IR-, UV-vis-NIR spectroscopy, EPR and SQUID measurements. It is shown that C(60)(.-) exists as a single-bonded diamagnetic (C60-)2 dimer in 1, 2, 4, 5, and 8 at low temperatures (1.9-250 K). The dimers dissociate above 160-250 K depending on donor and solvent molecules involved in the complex. C60(.-) dimerizes reversibly and shows a small hysteresis (<2 K) at slow cooling and heating rates. The single-bonded diamagnetic (C70-)2 dimers are also formed in 6, 9, and 10 and begin to dissociate only above 250-360 K. The IR and UV-vis-NIR spectra of sigma-bonded negatively charged fullerenes are presented. 相似文献
46.
New molecular complexes of C60 with metal(II) dibenzyldithiocarbamates, M(dbdtc)2.C60.0.5(C6H5Cl), where M=Cu(II), Ni(II), Pd(II), and Pt(II) and an ionic multicomponent complex [Cr(I)(C6H6)2*+].(C60*-).0.5[Pd(dbdtc)2] (Cr(C6H6)2: bis(benzene)chromium) were obtained. According to IR, UV-visible-NIR, and EPR spectra, involve neutral components, whereas 5 comprises neutral Pd(dbdtc)2 and C60*- and Cr(I)(C6H6)2*+ radical ions. The crystal structure of at 90 K reveals strongly puckered fullerene layers alternating with those composed of Pd(dbdtc)2. The Cr(I)(C6H6)2*+ radical cations are arranged between the layers. Fullerene radical anions form pairs within the layer with an interfullerene C...C contact of 3.092(2) A, indicating their monomeric state at 90 K. This contact is essentially shorter than the sum of van der Waals radii of two carbon atoms, and consequently, C60*- can dimerize. According to SQUID and EPR, single-bonded diamagnetic (C60-)2 dimers form in below 150-130 K on slow cooling and dissociate above 150-170 K on heating. The hysteresis was estimated to be 20 K. For the (C60-)2 dimers in, the dissociation temperature is the lowest among those for ionic complexes of C60 (160-250 K). Fast cooling of the crystals within 10 min from room temperature down to 100 K shifts dimerization temperatures to lower than 60 K. This shift is responsible for the retention of a monomeric phase of at 90 K in the X-ray diffraction experiment. 相似文献
47.
A. N. Lapshin V. A. Smirnov R. N. Lyubovskaya N. F. Goldshleger 《Russian Chemical Bulletin》2005,54(10):2338-2342
Axial coordination of the pyrrolidine nitrogen atom in cis-1,3-di(2-pyridyl)[60]fullereno[1,2-c]pyrrolidine to zinc meso-tetraphenylporphyrinate in cyclohexane gives rise to a donor-acceptor complex. The formation constant of the 1: 1 porphyrin—fullerenopyrrolidine
complex was determined by spectrophotometric and fluorescence titration. The values of the constant estimated by spectrophotometric
and fluorescence methods are 1.2·104 and 9.7·103 L mol−1, respectively.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2265–2269, October, 2005. 相似文献
48.
S. V. Konovalikhin G. V. Shilov O. A. D'yachenko R. N. Lyubovskaya M. Z. Aldoshina R. B. Lyubovskii 《Russian Chemical Bulletin》1992,41(4):704-709
The composition and structure of the radical-ion salt (ET)
2
[Hg(SCN)
2
Cl], a new organic metal withT
M-D=50 K, were established in an x-ray structure investigation. Principal crystallographic data:a=36.69(1),b=8.302(8),c=11.732(8) Å, =90.02(6)°, space groupCc, Z=4,d
calc=2.08 g/cm
3
,R=0.067. The crystal structure of the salt consists of an alternation of organic (cationic) and inorganic (anionic) layers along the axisa. The anionic layer consists of the polymeric chains in which the [Hg(SCN)
2
Cl]– ions are linked together along the axisc through secondary Hg···N bonds with lengths of 2.75(3) and 2.98(8) Å. On account of these interactions the trigonal configuration of the bonds of the Hg atom is built up to trigonal-bipyramidal. In the organic layer with a structure of the type the ET cations form dimers with an interplanar distance of 3.53 Å. ET cations belonging to neighboring dimers are linked together through shortened intermolecular S...S contacts with lengths of 3.40–3.50(2) Å.Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 903–909, April, 1992. 相似文献
49.
E. I. Yudanova D. V. Konarev L. L. Gumanov R. N. Lyubovskaya 《Russian Chemical Bulletin》1999,48(4):718-721
Complexes of fullerenes C60 and C70 with cobalt(II) and manganese(II) tetraphenylporphyrinates of compositions Mn(TPP)·(C60)2(CS2)1.5 (1), Mn(TPP)·C70(CS2)
x
, wherex<=1.25 (2), Co(TPP)·C60(CS2)0.5 (3), and Co(TPP)·C70(CS2)
x
, wherex<0.25 (4), were synthesized and studied by ESR spectroscopy. At 77 K, complexes1 and2 have singlet ESR spectra characteristic of the low-spin (S=1/2) state of MnII, withg=2.002 and linewidths of 250 G and 300 G, respectively, and differing significantly from that of the initial MnII(TPP) (g
1=5.9 andg=2.0,S=5/2). The spectra of complexes1 and2 exposed to oxygen exhibit hyperfine structure due to interaction with55Mn and14N nuclei. The ESR spectra of complexes3 and4 are asymmetric (<g>=2.4, ΔH
pp=(500–600) G), which is due to the overlap of parallel and perpendicular spectral components. The absence of ESR signals from
C60
.− and C70
.− radical anions makes it possible to conclude that the formation of complexes1–4 is not accompanied by electron transfer from Co(TPP) and Mn(TPP) to fullerences C60 and C70.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 722–725, April, 1999. 相似文献
50.
A. V. Kornilov V. M. Pudalov A. P. Kochkin R. N. Lyubovskaya R. B. Lyubovskii 《Journal of Experimental and Theoretical Physics》1999,88(6):1198-1201
The conductivity of single crystals of the organic conductor (ET)4Hg3I8 [ET-bis(ethylendithio)tetrathiafulvalene] has been investigated at temperatures from 4.2 to 360 K and pressures of up to
75 kbar. Two first-order phase transitions have been detected at room temperature at pressures of 2.75 and 6.7 kbar. On the
basis of the experimental data, the p-Tphase diagram for the first-order phase transitions has been plotted. The unusual shape of the phase diagram (a slow monotonic
growth of the transition temperature with a slope dT/dp=4 deg/kbar followed by a sharp drop around the point p
0=6.5 kbar, T
0=324 K) has been analyzed using the Landau theory of second-order phase transitions. Our analysis supports the hypothesis
of a second-order phase transition around this point and also exhibits satisfactory agreement between calculations and the
experimental curves of the first-order phase transitions.
Zh. éksp. Teor. Fiz. 115, 2190–2196 (June 1999) 相似文献