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1.
毛礼胜  沈琪  林永华 《有机化学》1994,14(2):215-219
本文合成了配合物[ Li(DME)~3] [(t-BuCp)~2Nd(NP-h~2)~2]·1/2 DME 并测定了其晶体结构. 晶体结构利用Patterson 和Fourier 技术得到, 并经最小二乘法修正.转入各向异性温度因子后, 按理论模型投入所有氢原子坐标, 最后一致性因子R=0.042, Rw=0.040.  相似文献   

2.
四— (对—磺酸基 )苯基卟啉 ( TSPP4-)作为超灵敏显色剂和电极修饰材料在光谱分析和电化学分析中有重要应用。它在酸性条件下以质子化二酸 H2 4TSPP4-的形式存在。七十年代 ,Paster-nack等人曾发现 H2 4TSPP4-的电子吸收谱随溶液 p H的改变产生复杂的变化 ,并推测与H2 4TSPP4-的分子缔合有关 [1] 。近年来 ,H2 4TSPP4-的分子缔合及其光谱性质重新引起人们的兴趣。基于光谱实验结果 [2 -6] ,一些作者认为 TSPP在强酸性条件下形成准一维的有序结构 ,类似于菁染料的 J-聚集体 ( Jelley- Scheibe聚集体 ) [3— 5 ] 。目前对 …  相似文献   

3.
<正> The title complex crystallizes in the orthorhombic space group Pna21 with Mr = 570. 8, a = 16. 927(6), b = 18.942(7), c=10. 618(5)(?) and Z = 4. The structure was solved by Patterson and Fourier techniques and refined by block-diagonal least squares techniques to R = 0. 090 and Rw = 0. 093 for 1553 reflections with I>1. 5σ(I). The Pr3+ ion is bonded to five carbon atoms of cyclopentadi-enyl ring, four μ-chlorine atoms and one oxygen atom of THF in an octahedral geometry with the Pr-C distances in the range 2. 6.7 - 2. 79(?)(av. 2. 76(?)) , the Pr-Cl distances in the range 2. 81 - 2. 92(?) (av. 2. 86(?)) and the Pr -O distance of 2. 51 (?). Each Li+ ion is coordinated by two μ-chlorine atoms and two oxygen atoms from THF in a tetrahedral geometry with the Li-Cl distances in the range 2. 24 - 2. 61(?) (av. 2. 43(?)) and the Li -O distances in the range 1. 86-1. 94(?)(av. 1. 91(?)). The Pr atom and the two Li atoms are bridged asymmetrically by the chlorine atoms.  相似文献   

4.
(R)-[1-(Dimethylamino)ethyl]benzene reacts with nBuLi in a 1:1 molar ratio in pentane to quantitatively yield a unique hetero-aggregate (2 a) containing the lithiated arene, unreacted nBuLi, and the complexed parent arene in a 1:1:1 ratio. As a model compound, [Li(4)(C(6)H(4)CH(Me)NMe(2)-2)(2)(nBu)(2)] (2 b) was prepared from the quantitative redistribution reaction of the parent lithiated arene Li(C(6)H(4)CH(Me)NMe(2)-2) with nBuLi in a 1:1 molar ratio. The mono-Et(2)O adduct [Li(4)(C(6)H(4)CH(Me)NMe(2)-2)(2)(nBu)(2)(OEt(2))] (2 c) and the bis-Et(2)O adduct [Li(4)(C(6)H(4)CH(Me)NMe(2)-2)(2)(nBu)(2)(OEt(2))(2)] (2 d) were obtained by re-crystallization of 2 b from pentane/Et(2)O and pure Et(2)O, respectively. The single-crystal X-ray structure determinations of 2 b-d show that the overall structural motifs of all three derivatives are closely related. They are all tetranuclear Li aggregates in which the four Li atoms are arranged in an almost regular tetrahedron. These structures can be described as consisting of two linked dimeric units: one Li(2)Ar(2) dimer and a hypothetical Li(2)nBu(2) dimer. The stereochemical aspects of the chiral Li(2)Ar(2) fragment are discussed. The structures as observed in the solid state are apparently retained in solution as revealed by a combination of cryoscopy and (1)H, (13)C, and (6)Li NMR spectroscopy.  相似文献   

5.
We compute and analyze the potential energy for the twenty-six lowest-lying states of Li2 which correspond asymptotically to the interaction of Li(2s2S) with Li(2s2S). Li(2p2P) or Li(3s2S), and the interaction Li(2p2P) with Li(2p2P) to obtain the leading terms of the first-order electrostatic energies, and the second-order dispersion energies. Ion-pair perturbations are found to dominate the potential curves of several states. The polarizabilities of Li 2s, 2p and 3s in various fields are calculated.  相似文献   

6.
Reaction of HN(PiPr2)2 with one equivalent of selenium in hexane at room temperature yields the monoselenide as the P-H tautomer Se=PiPr2-N=P(H)iPr2 (2b). Deprotonation of 2b with n butyllithium in the presence of TMEDA at -78 degrees C followed by addition of tellurium produces the air-sensitive, mixed chalcogenido complex [(TMEDA)Li(SePiPr2)(TePiPr2)N] (8Li) in >97% purity after recrystallisation. Similarly, deprotonation of Te=PiPr2-N=P(H)iPr2 (2c), followed by addition of sulfur, gives the sulfur analogue [(TMEDA)Li(SPiPr2)(TePiPr2)N] (7Li) in >99% purity. The symmetrical complexes [(TMEDA)Li(SePiPr2)2N] (4Li) and [(TMEDA)Li(TePiPr2)2N] (5Li) are produced by similar methods. Compounds 2b, 4Li, 5Li, 7Li and 8Li were characterised in solution by multinuclear (1H, 31P, 77Se and 125Te) NMR spectroscopy and their solid-state structures were determined by X-ray crystallography. The X-ray crystal structures of the polymeric chains [NaN(EPiPr2)2]infinity (4Na, E = Se and 5Na, E = Te) are also reported.  相似文献   

7.
Syntheses and Structures of the Lithiumtitanates(III)/(IV) (py)2Li[(py)2Ti(OPh)4] and (py)2Li[(py)Ti(OPh)5] The new lithiumtitanates (py)2Li[(py)2Ti(OPh)4] ( 1 ) and (py)2Li[(py)Ti(OPh)5] ( 2 ) have been obtained from the reaction of titaniumtrichloride (respectively titaniumtetrachloride 2 ) with LiOPh in the presence of the base pyridine (py). The crystal structures of both compounds show that the titanium atoms are in the centres of distorted octahedral coordination figures. In compound 1 , four oxygen and two nitrogen atoms (in cis orientation) are bonded to titanium, whereas in 2 , five oxygen and one nitrogen atom form the coordination polyeder around titanium. In both compounds, the lithium atoms are attached through phenolate bridges to the octahedra. The titanate (py)2Li[(py)2Ti(OPh)4] ( 1 ) has a single absorption band in the visible region of the UV‐spectrum showing a shoulder shifted to the bathochromic region, due to the Jahn‐Teller‐effect for d1‐systems.  相似文献   

8.
The evolution of the Li-ion displacements in the 3D interstitial pathways of the cubic garnet-type Li(7)La(3)Zr(2)O(12), cubic Li(7)La(3)Zr(2)O(12), was investigated with high-temperature neutron diffraction (HTND) from RT to 600 °C; the maximum-entropy method (MEM) was applied to estimate the Li nuclear-density distribution. Temperature-driven Li displacements were observed; the displacements indicate that the conduction pathways in the garnet framework are restricted to diffusion through the tetrahedral sites of the interstitial space.  相似文献   

9.
本文合成了组成为(LaCl)DME(u~2-Cl)~5(u~3-Cl)(La.DME)-Li(THF)~2的新型桥式链状配合物, 并测定了晶体结构。  相似文献   

10.
The title compound [2,6-Mes(2)C(2)H(3)](2)Ga(+)Li[Al(OCH(CF(3))(2))(4)](2)(-), 1, containing a linear two-coordinate gallium cation, has been obtained by metathesis reaction of [2,6-Mes(2)C(2)H(3)](2)GaCl with 2 equiv of Li[Al(OCH(CF(3))(2))(4)] in C(6)H(5)Cl solution at room temperature. Compound 1 has been characterized by (1)H, (13)C((1)H), (19)F, and (27)Al NMR spectroscopy and X-ray crystallography. Compound 1 consists of isolated [2,6-Mes(2)C(6)H(3)](2)Ga(+) cations and Li[Al(OCH(CF(3))(2))(4)](2)(-) anions. The C-Ga-C angle is 175.69(7) degrees, and the Ga-C distances are 1.9130(14) and 1.9145(16) A. The title compound is remarkably stable, is only a weak Lewis acid, and polymerizes cyclohexene oxide.  相似文献   

11.
Todorov I  Sevov SC 《Inorganic chemistry》2005,44(15):5361-5369
The title compounds were synthesized from the elements by heating the corresponding mixtures at high temperature. Their structures were determined from single-crystal X-ray diffraction. Li(9)(-)(x)()EuSn(6+)(x)(), Li(9)(-)(x)()CaSn(6+)(x)(), Li(5)Ca(7)Sn(11), and Li(6)Eu(5)Sn(9) contain columns of stacked aromatic pentagons of Sn(5)(6)(-) that are analogous to the cyclopentadienyl anion C(5)H(5)(-). The pentagons are separated with Ca(2+) or Eu(2+) in the columns and resemble a polymeric metallocene. In addition to the columns, the isostructural Li(9)(-)(x)()EuSn(6+)(x)() and Li(9)(-)(x)()CaSn(6+)(x)() contain isolated tin atoms and bent tin trimers while Li(5)Ca(7)Sn(11) and Li(6)Eu(5)Sn(9) contain flat zigzag hexamers and flat zigzag infinite chains of tin, respectively. The isostructural LiMgEu(2)Sn(3) and LiMgSr(2)Sn(3) do not contain columns of pentagons but only flat zigzag infinite chains of tin. The aromaticity of the pentagons and the conjugation of the pi-systems of the hexamers and the infinite chains are discussed. The title compounds are also characterized by magnetic and conductivity measurements.  相似文献   

12.
Tris(2-((pyrid-2-ylmethyl)uredio)ethyl)amine (2) and its perchlorate salt, 2.HClO(4), bind with Li+ in nitromethane in a 1:1 fashion. The stability constants of K(Li+) and K(H)(Li+) were found to be 112 +/- 25 and 130 +/- 30 M(-)(1) in CD(3)NO(2), respectively. Formation of the 1:1 complexes were further evidenced by electrospray ionization mass spectrometry (ESI-MS). The slight increase, or at least the same order of magnitude, of K(H)(Li+) compared to K(Li+) points to a remarkable preorganization of the protonated podand in 2.HClO(4), that essentially overcomes the increased Columbic repulsion occurring on complexation to Li+.  相似文献   

13.
The Li+-(H2)n n=1-3 complexes are investigated through infrared spectra recorded in the H-H stretch region (3980-4120 cm-1) and through ab initio calculations at the MP2/aug-cc-pVQZ level. The rotationally resolved H-H stretch band of Li+-H2 is centered at 4053.4 cm-1 [a -108 cm-1 shift from the Q1(0) transition of H2]. The spectrum exhibits rotational substructure consistent with the complex possessing a T-shaped equilibrium geometry, with the Li+ ion attached to a slightly perturbed H2 molecule. Around 100 rovibrational transitions belonging to parallel Ka=0-0, 1-1, 2-2, and 3-3 subbands are observed. The Ka=0-0 and 1-1 transitions are fitted by a Watson A-reduced Hamiltonian yielding effective molecular parameters. The vibrationally averaged intermolecular separation in the ground vibrational state is estimated as 2.056 A increasing by 0.004 A when the H2 subunit is vibrationally excited. The spectroscopic data are compared to results from rovibrational calculations using recent three dimensional Li+-H2 potential energy surfaces [Martinazzo et al., J. Chem. Phys. 119, 11241 (2003); Kraemer and Spirko, Chem. Phys. 330, 190 (2006)]. The H-H stretch band of Li+-(H2)2, which is centered at 4055.5 cm-1 also exhibits resolved rovibrational structure. The spectroscopic data along with ab initio calculations support a H2-Li+-H2 geometry, in which the two H2 molecules are disposed on opposite sides of the central Li+ ion. The two equivalent Li+...H2 bonds have approximately the same length as the intermolecular bond in Li+-H2. The Li+-(H2)3 cluster is predicted to possess a trigonal structure in which a central Li+ ion is surrounded by three equivalent H2 molecules. Its infrared spectrum features a broad unresolved band centered at 4060 cm-1.  相似文献   

14.
The treatment of Me3SiN=P(NHBut)3 with three equivalents of LiBun in toluene produces (Li3(P(NBut)3(NSiMe3)))2 comprised of a Li6N6 cyclic ladder capped on the two hexagonal faces by mu 3-PNSiMe3 groups; the corresponding reaction of O=P(NHBut)3 yields the face-sharing double-cubane (Li2(THF)P(O)(NBut)2(NHBut))2 with a central Li2O2 ring.  相似文献   

15.
The complex [{(TMS)2N}4(mu4-Cl)Sm4(mu-SPh)4(mu3-Cl)Li(THF)] has been formed by protonolysis of [(Me3Si)2N]3Sm(mu-Cl)Li(THF)3 with 1 equiv of HSPh, which contains a square array of Sm(III) ions connected by a central mu4-Cl ligand. The edges of the square Sm4 array are bridged by four mu3-Cl and four mu-SPh ligands. The four Sm atoms and Li atom are connected by four mu3-Cl ligands.  相似文献   

16.
The hydrolysis of [ClP(mu-NtBu)]2 with H2O-Et3N in thf, followed by in situ lithiation with nBuLi gives the Li13 cage [[[O-P(mu-NtBu)]2Li2]3(LiCl)6Li(Cl/OnBu)0.5(thf)7], containing a [O-P(mu-NtBu)]2(2-) dianion that is isoelectronic with ligands of the type [(RN)P(mu-NR)]2(2-).  相似文献   

17.
五元交互体系Li+,Na+,K+//CO32-,Cl--H2O在298.15K的相平衡研究   总被引:1,自引:0,他引:1  
针对西藏扎布耶盐湖卤水组成,采用等温溶解平衡法研究了五元交互体系Li+,Na+,K+//CO32-,Cl--H2O于298.15K时的相平衡,并绘制了相图(空间立体图和Li2CO3饱和的投影图).结果表明,该五元体系相图含有7个结晶区、13条单变量线和4个无变量点.7个结晶区由6个单盐结晶区和1个复盐结晶区组成,分别为LiCl·H2O,NaCl,KCl,Li2CO3,K2CO3·3/2H2O,Na2CO3·10H2O和NaKCO3·6H2O,没有形成固溶体和天然碱(Na2CO3·NaHCO3·2H2O).4个无变量点标记成K1,K2,K3和K4,所对应的平衡固相盐分别是:Li2CO3+NaKCO3·6H2O+Na2CO3·10H2O+KCl,Li2CO3+NaKCO3·6H2O+K2CO3·3/2H2O+KCl,Li2CO3+NaCl+KCl+LiCl·H2O和Li2CO3+NaCl+Na2CO3·10H2O+KCl.  相似文献   

18.
The following crystalline, or microcrystalline (4), metal diamides have been prepared under mild conditions from the N,N'-disubstituted 1,2-diaminobenzene [{N(R)H}2C6H4-1,2] (H(2): R = CH2But; H2L': R = SiMe2NPri2): [Li(thf)(mu-L)(mu-I)Ca(thf)] (1), [Li(thf)4][{Zn(mu-L)}3(mu3-Cl)] (2), [Li(thf)4][Zn(L)2] (3), [{Li(OEt2)(mu-L)Zn}2(mu-L)] (4), [Li(OEt2)(mu-L)Zn(mu-L)Zn(LH)] (5) and [Li(thf)(mu-L')Li(thf)2] (6). Compounds 1-5 were obtained from [Li2(L)] and CaI2 (1) or ZnCl2 (2-5) while 6 was derived from H2(L') and LiBun. Compound 5 was isolated as a very minor by-product from the synthesis of 4, and is assumed to have been formed therefrom by adventitious hydrolysis. The green salt 3 was paramagnetic with the negative charge uniformly delocalised on the two ligands. The other compounds were colourless and diamagnetic. The X-ray structures of each, except 4, are reported and discussed.  相似文献   

19.
Li0.33MnO2 cathode material was synthesized by solid state reaction which showed a monoclinic structure.In situ synchrotron diffraction showed a reversible structural transition of Li0.33MnO2 during Li+ insertion/extraction.However,it is difficult to determine the crystal structure of lithiated Li0.33+xMnO2 based on their poorly resolved diffraction patterns.This difficulty was successfully resolved by X-ray absorption spectroscopy(XAS) and Raman scattering which are sensitive to the short-range ordering of...  相似文献   

20.
Reaction of TiF4 and LiORf (Rf = C(CF3)2Ph) in the donor solvent-THF lead to the isolation of the heterometallic lithium-titanium complex (THF)2Li(mu-F)2Ti(ORf)2(mu-F)2Ti(ORf)(2)(mu-F)2Li(THF)2 (1) and Ti(ORf)4 alkoxide (2). Interaction of TiF4 and LiORf in the non-coordinating and low polar toluene yielded only Ti(ORf)4 (2). Compounds 1 and 2 were characterized by X-ray single-crystal analysis, IR, NMR and mass spectrometry. Compound 1 is a centrosymmetric fluorine bridged dimer and contains the Li(mu-F)2Ti(mu-F)2Ti(mu-F)2Li cage. Complex 2 containing four bulky ligands is monomeric. NMR evidence is presented that the TiF4 and LiORf in THF solution gave lithium-titanium heterometallic complexes containing Li-(mu-F)-Ti and the Ti-(mu-F)-Ti bonds.  相似文献   

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