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1.
[(4氮间杂六甲基十四烷环)~(-4)·2Mn~(2+)]·4HCl·[4氮间杂六甲基十四烷环)·2H_2O]的晶体结构已用单晶X线衍射技术测定完成。它属于三斜晶系,P_1空间群,晶胞参数a=9.028(2),b=11.055(2),c=12.202(4),α=71.70(2),B=88.41(2),γ=75.32(2)~°,Z=1。对于2597个可观察独立反射计算R=0.073。结构分析证实,该晶体存在有四类物种,由负4价的四氮间杂六甲基十四烷环(简称电负性大环Ⅱ),2个Mn~(2+)正离子,4个HCl分子和一个携带2个结晶水的4氮间杂六甲基十四烷环(简称电中性大环Ⅰ)组成。 4个HCl分子处于电负性大环Ⅱ的周围,大环Ⅱ和Mn~(2+)离子间按离子键特点取空间最稳定构型与电中性大环Ⅰ沿c方向周期性交替排布,构成四元包合物O~-、N~-、Cl~-等电负性强的离子之间形成很强的H键网。 六十年代以来,以四氨间杂六甲基十四烷环作配体,以Co~(2+)、Co~(3+)、Ni~(2+)等金属离子为络合中心的大环络合物,国外已有许多报导。这些结构的共同特点是大环配体的4个氮原子围绕金属离子以构成四配位或六配位结构,研究表明,络合以后金属的电子组态发生了变化。 近来,我们将Mn~(2+)与上述的配体反应,结果得到与上述结构绝然不同的化合物。NMR谱证实,该化合物中包含电中性和电负性两种大环。环伏安法测其锰离子是2价正离子(详见  相似文献   

2.
The complex of [4Ni(salen)·GGH] CLO_4·EtOH·H_2O has been synthesized and studied by X-ray single crystal analysis. The results show that there are both intra-unit hydrogen bonds in the [4Ni(salen)·GGH]~+ and inter-unit hydrogen bonds between the two [4Ni(salen)·GGH]~+. Ni(salen) in the unit are still centrosymmetric dimers with planar structure. Imide N(10)—H(10) in the [GGH]~+ bonds with one phenolic oxygen 0(7) of Ni(salen) dimer in the same unit. Two H atoms of amino group N(9)— H [H(A), H(C)] in the glycylglycine perchlorate interact with phenolic oxygen [0(3), 0(5)] of [4Ni(salen)·GGH]~+ through two strong hydrogen bonds respectively.  相似文献   

3.
Strain measurement and quasiequilibrium thermogravimetry were used to study the dissociation processes of two clathrates, [Ni(MePy)4(NCS)2]·(MePy) and [Cu(MePy)4(NCS)2]·2/3(MePy), accompanied by the liberation of MePy into the gaseous phase. In the Ni clathrate dissociation process in the temperature range 298–368 K the liberated MePy was redistributed between the solid clathrate and gaseous phases; the MePy vapour pressure over the clathrate is a function of temperature and the guest contenty, which agrees with the presence in the MePy-[Ni(MePy)4(NCS)2] system of a wide range of -clathrate solutions, [Ni(MePy)4(NCS)2y(MePy). The same methods used to study the Cu clathrate dissociation resulted in conclusions different from those obtained for the dissociation process of the above clathrate: the process is described by the equation [Cu(MePy)4(NCS)2]·2/3(MePy)solid =[Cu(MePy)2(NCS)2]solid+22/3(MePy)gas; the temperature dependence of the Mepy vapour pressure over the solid sample does not depend on its composition, which points to the absence from the system of solid solutions based on the clathrate. Standard changes of the enthalpy, entropy, and isobaric-isothermal reaction potential for the temperature range 292–325 K are equal to 178.6±1.7 kJ (mole of clathrate)–1, 463±5.6 J (mole of clathrate)–1 K–1, and 40.4±2.4 kJ (mole of clathrate)–1, respectively.  相似文献   

4.
The title complex was synthesized in an aqueous solution and its crystal structure was determined by X-ray diffraction. The crystal is rhombohedral, space group R3 with a=1.947 0(3) nm, b=1.947 0(3) nm, c=1.768 3(3) nm, α=90°, β=90°, γ=120°, V=5.805(2) nm3, Z=3, the final R value is 0.051 2. The complex contains a novel tetranuclear cation with four Er3+ ions connected by four μ3-OH ions and six bridging carboxyl groups. Each erbium ion is coordinated by three μ3-OH, three carboxylic oxygen atoms from three L-proline, and two or one oxygen atoms from water molecules.  相似文献   

5.
Novel compounds of Gd(III), Tb(III), Er(III), and Tm(III) with 4,4??-bipyridine (4-bpy) and trichloroacetates are prepared. The title compounds are isomorphic and isostructural in the solid state. All atoms in the studied compound lie in general positions of the Cc space group. The coordination polyhedra around central atoms can be described as bicapped trigonal prisms slightly disordered towards a square antiprism. All 4-bpy molecules are located in the outer coordination sphere together with four trichloroacetate anions and four water molecules. One of the nitrogen atoms of one 4-bpy is protonated due to stoichiometry.  相似文献   

6.
Differentkindsofcopper(II)carboxylateadductshavebeensynthesizedandalsodinuclearcopper(Il)complexeshavebeenearlystUdiedasusefulmodelstoestablishmagneto-structUra1correlationsforspinexchangebetWeenmetalions.CostaIshowedthestructureof[Cu,(ll-OOCFc),(bpy),(ClO')(CH,Oand[Cu,(n-OOCFc),(bpy)(CH,OH),]' .Asfarasweknow,thecopper(II)compoundscontainingFCAandphenhavenotbeenreported.TheligandofFCAwassynthesizedaccordingtothefoIlowingscheme2.3:Asolutioncontainingl98mg(lmmol)ofphenandl5mLofmet…  相似文献   

7.
This research was done on hureaulite samples from the Cigana claim, a lithium bearing pegmatite with triphylite and spodumene. The mine is located in Conselheiro Pena, east of Minas Gerais. Chemical analysis was carried out by Electron Microprobe analysis and indicated a manganese rich phase with partial substitution of iron. The calculated chemical formula of the studied sample is: (Mn3.23, Fe1.04, Ca0.19, Mg0.13)(PO4)2.7(HPO4)2.6(OH)4.78. The Raman spectrum of hureaulite is dominated by an intense sharp band at 959 cm−1 assigned to PO stretching vibrations of HPO42− units. The Raman band at 989 cm−1 is assigned to the PO43− stretching vibration. Raman bands at 1007, 1024, 1047, and 1083 cm−1 are attributed to both the HOP and PO antisymmetric stretching vibrations of HPO42− and PO43− units. A set of Raman bands at 531, 543, 564 and 582 cm−1 are assigned to the ν4 bending modes of the HPO42− and PO43− units. Raman bands observed at 414, and 455 cm−1 are attributed to the ν2 HPO42− and PO43− units. The intense A series of Raman and infrared bands in the OH stretching region are assigned to water stretching vibrations. Based upon the position of these bands hydrogen bond distances are calculated. Hydrogen bond distances are short indicating very strong hydrogen bonding in the hureaulite structure. A combination of Raman and infrared spectroscopy enabled aspects of the molecular structure of the mineral hureaulite to be understood.  相似文献   

8.
合成了一个五核簇合物[MoS4CU4(dppm)4](NCS)2·4(CH3)2CHOH,用单晶X-射线衍射方法测得该晶体属于单斜晶系,空间群P21/a,晶胞参数a=2.0536(2),b=1.8095(2),c=3.1951(4)nm,β=100.220(4)°,V=11.6846(23)nm3,Z=4,Dc=1.349g/cm3,μ=10.87cm-1,F(000)=4896,R=0.085,Rw=0.089.其二价簇阳离子是一个MoS4单元被一个十六原子环[-Cu-P-C-P-]4包围在中心的"主客体"结构.  相似文献   

9.
Two Cu(II) hydroxo succinates [Cu3(H2O)2(OH)2(C4H4O4)2]?·?4H2O (1) and [Cu4(H2O)2(OH)4(C4H4O4)2]?·?5H2O (2) and one Cu(II) hydroxo glutarate [Cu5(OH)6(C5H6O4)2]?·?4H2O (3) have been prepared and structurally characterized by single crystal X-ray diffraction methods. They feature 1D and 2D copper oxygen connectivity of elongated {CuO6} octahedra in “4?+?1?+?1” and “4?+?2” coordination geometries. Within 1, linear trimers of three edge-sharing {CuO6} octahedra are connected into copper oxygen chains, which are bridged by the anti conformational succinate anions to generate 2D layers with mono terminally coordinating gauche succinate anions on both sides. The layers are assembled into a 3D framework by interlayer hydrogen bonds with lattice H2O molecules distributed in channels. Different from 1, the principal building units in 2 are linear tetramers of four edge-sharing {CuO6} octahedra. The tetramers are condensed into copper oxygen chains and the succinate anions interlink them into a 3D framework with triangular channels filled by lattice H2O molecules. The {CuO6} octahedra in 3 are edge-shared to form unprecedented 2D inorganic layers with mono terminally coordinating glutarate anions on both sides. Interlayer hydrogen bonding interactions are responsible for supramolecular assembly of the layers into a 3D framework with lattice H2O molecules in the channels. The inorganic layers in 3 can be described as hexagonal close packing of oxygen atoms with the Cu atoms in the octahedral cavities. The title compounds were further characterized by elemental analyses, IR spectra and thermal analyses.  相似文献   

10.
In light of the important recent synthesis of a stable tetrasilacyclobutadiene dianion compound by Sekiguchi and co-workers and the absence of theoretical studies, ab initio methods have been used to investigate this dianion and a number of related species. These theoretical methods predict multiple minima for each compound, and most minima contain folded and bicyclic silicon rings. For (Si(4)H(4))(2-), (Si(4)H(4))(2-)·2Li(+), [Si(4)(SiH(3))(4)](2-)·2Li(+), [Si(4)(SiH(3))(4)](2-)·2Na(+), and [Si(4)(SiH(3))(4)](2-)·2K(+), respectively, the energetically lowest-lying structures are designated A-3 (C(2v) symmetry), B-8 (C(1) symmetry), C-1 (C(2) symmetry), D-1 (C(2) symmetry), and E-1 (C(2h) symmetry). None of these structures satisfies both the ring planarity and the cyclic bond equalization criteria of aromaticity. However, all of the representative NICS values of these lowest-lying structures are negative, indicating some aromatic character. Especially, structures C-1 and D-1 of C(2) symmetry effectively satisfy the criteria of aromaticity due to the slightly trapezoidal silicon rings, which are nearly planar with nearly equal bond lengths. SiH(3) substitution for hydrogen in (Si(4)H(4))(2-)·2Li(+) significantly reduces the degree of aromaticity, as reflected in the substantially smaller NICS absolute values for [Si(4)(SiH(3))(4)](2-)·2Li(+) than those of (Si(4)H(4))(2-) and (Si(4)H(4))(2-)·2Li(+). The aromaticity is further weakened in [Si(4)(SiH(3))(4)](2-)·2Na(+) and [Si(4)(SiH(3))(4)](2-)·2K(+) by replacing lithium with the sodium and potassium cations.  相似文献   

11.
Two new hydrogen storage compounds,Na Zn(BH_4)_3·en and Na Zn(BH_4)_3·2en(en=ethylene diamine)are synthesized by a solution method.They can release 6.4 wt% and 6.3 wt% pure hydrogen below 200℃,respectively,demonstrating the potential to be used as hydrogen carriers.Additionally,their dehydrogenation products,thermodynamics and kinetics are well characterized and analyzed.Results shows that the stronger Zn-N interactions and the Hδ~+–Hδ~- interactions are significant for their stability below 100℃,relatively low decomposition temperatures and elimination of gas impurities.  相似文献   

12.
Density functional theory (DFT) is used to investigate the structural properties of Ni(II) cubane [Ni4(ampdH)4Cl4]·MeCN. The structural features and ground state geometry calculations are computed at the B3LYP/6-31G* (LANL2DZ) level of theory. We shed light on the highest occupied molecular orbital and lowest unoccupied molecular orbital. The absorption spectrum is calculated using time-dependent DFT. The absorption wavelengths are calculated using different functionals, i.e., pw91pw91, B3LYP, BHandHLYP, CAM-B3LYP, LC-BLYP, and M06. The LC-BLYP is in good agreement with the experimental data.  相似文献   

13.
14.
15.
<正> {[Eu(OOCCH2NHCOCH2NH3)2(H2O)2]·(ClO4)3·2H2O}2,Mr = 1572,P21/n,a=12. 014(4),b=8. 910(5),c=22. 749(5)A ,β=91. 73(3)°,V = 2034 A3,Z=2,Dx=2. 15g·cm-3,λ(MoKa) = 0. 71073A,R=0. 060 for 3107 unique observed reflections (I≥3σ(I)). The complex cation is of one-dimensional chain structure in which the basic unit is a dinuclear complex and the gly-gly ligands are coordinated to metal atoms in two kinds of forms. The overall structure of the dinuclear unit is dioxo and dicarboxyl-bridged.  相似文献   

16.
四核银原子簇化合物Ag_4(α-C_(10)H_7CS_2)_4(Py)_4·2Py由α-萘荒酸与硝酸银在有机溶剂中反应,经吡啶重结晶获得单晶。由于反应中采用不同的银盐与α-萘荒酸的投料比(1:2与1:4),得到了两种颜色的晶体(甲和乙)。用X射线单晶衍射法测定了它们的晶体结构。晶体甲的空间群为C_(2h)~5—P2_1/a。晶胞参数:a=2.2822(4)(?),b=12.803(4)(?),c=24.444(7)(?),β=103.90(2)°,V=6933.14(?)~3,Z=4。晶体乙的空间群为c_(2h)~6—c2/c。晶胞参数:a=29.150(2)(?),b=12.789(3)(?),c=24.413(2)(?),β=130.56(4)°,V=6914.38(?)~3,Z=4。Ag_4(α-C_(10)H_7CS_2)_4(Py)_4在两种晶体中的空间构型基本相同,差别只在于分子的对称性上。晶体乙中,分子处在二重轴上,分子的对称性较高。本文只报道晶体乙的结构测定和结构参数.3338个反射参与修正,最终的偏差因子R=0.093。分子中Ag_4呈压扁的四面体构型。六个Ag—Ag距离可分成两类,硫桥相连的Ag—Ag平均键长为2.924(?)(2.875—2.972(?)),表明有相当程度的金属键相互作用。不与硫桥相连的Ag—Ag距离为3.563(?)。  相似文献   

17.
Sulfur tetrafluoride and triethylamine react at low temperatures to form a 1?:?1 adduct. The unambiguous characterization of the SF(4)·N(C(2)H(5))(3), which is only stable at low temperature, proves the Lewis acid property of SF(4) towards organic Lewis bases. The S-N bond has a length of 2.384(2) ? and is an archetypical example of a dative S(IV)← N bonding modality.  相似文献   

18.
测定了三元体系La(ClO4)3-OCBAAP-H2O在30℃时的溶解度.结果表明,该体系有一个新固相(不一致溶解化合物)La(OCBAAP)4(ClO4)3·6H2O形成.参考该体系溶度图确定合成条件,合成了系列化合物Ln(OCBAAP)4(ClO4)3·nH2O(Ln=La,n=6;Ln=Pr,Nd,Sm,Gd,Yb,n=2).通过化学分析、元素分析、TG-DTG、IR和密度对化合物进行了表征,计算了La(OCBAAP)4(ClO4)3热分解过程各阶段的表观活化能.  相似文献   

19.
FewcompoundswithMninthe 5oxidationstatewerestructuraIlycharacterizedsofaLC.L.HilIlfirstdeterminedthecrystalstructUreoftheMn(V)complex:NMnTpMPP-Nitriodotrtrakis(p-methoxyphenyl)porphinnato-manganese(V).Thepapers'-'reportedseveralnovelmanganese(V)and(Vl)complexes.RecentpublicationshavebeenestablishedthatthecoordinationcompoundsofhighvaIentmanganesedisplaymanyinterestingfeatures.Theyshowabilitytoundergointramolecularinterligandormetal-ligandelectrontransferreaction,especiallyonthenatUreo…  相似文献   

20.
One new cadmium complex [Cd(phen)3]·(ClO4)2·(p-MBA)2·(H2O)2 has been hydro- thermally synthesized by reacting p-methylbenzoic acid (p-MBA), 1,10-phenanthroline (phen) and cadmium perchlorate. It crystallizes in the triclinic system, space group P, with a = 1.2809(3), b = 1.3431(3), c = 1.3734(3) nm, α = 84.259(4), β = 71.603(3), γ = 74.424(3)o, V = 2.1594(8) nm3, Dc = 1.532 g/cm3, Z = 2, F(000) = 1008, μ = 0.697 mm-1, R = 0.0646 and wR = 0.1648. The crystal structure shows that the cadmium ion is coordinated with six nitrogen atoms from three 1,10-phenanthroline molecules, forming a distorted octahedral coordination geometry. The result of electrochemical property analysis shows that the electron transfer in the electrode reaction is irreversible.  相似文献   

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