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1.
S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2001,64(2):629-636
Thermogravimetry (TG), differential thermal analysis (DTA) and other analytical methods have been applied to the investigation
of the thermal behaviour and structure of the complexes Mg(pc)(na)3⋅3H2O (I), Mg(pc)(py)2⋅2H2O (II),Mg(pc)(pic)2⋅2H2O (III) and Mg(pc)(caf)2⋅4H2O (IV), where pc=2,6- pyridinedicarboxylate, na=nicotinamide,py=pyridine, pic=γ-picoline and caf=caffeine. The thermal decomposition of these compounds is multi-stage processes. The chemical composition of the complexes,
the solid intermediates and the resultant products of thermolysis have been identified by means of elemental analysis and
complexometric titration. Schemes of destruction of these complexes are suggested. Heating of these compounds first resulted
in a release of water molecules. In complexes I, II and IV the loss of the molecular ligands (na, py and caf) occur (on the
TG curves) in one step (-2na, -2py and -2caf) and in complex III in two steps (-pic, -pic). The final product of the thermal
decomposition was MgO. The thermalstability of the complexes can be ordered in the sequence: IV<I<III<II. Nicotinamide, pyridine,
γ-picoline and caffeine were co-ordinated to Mg(II) through the N atom of the respective heterocyclic ring. IR data suggested
a unidentate co-ordination of carboxylates to Mg(II) in complexes I–IV.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Prof. Dr. Gui‐Ling Wang Yong‐Mei Tian Dr. Wen‐Bin Sun Bing‐Lu Han Mang‐Fei Yu Hui Xu Ting Gao 《无机化学与普通化学杂志》2011,637(11):1616-1621
The salen‐type ligand H2L [H2L = N,N′‐bis(salicylidene)‐1,2‐cyclohexanediamine] was utilized for the synthesis of two lanthanide(III) coordination polymers [LnH2L(NO3)3MeOH]n [Ln = Eu ( 1 ) and Ln = Lu ( 2 )]. The single‐crystal X‐ray diffraction analyses of 1 and 2 revealed that they are isomorphous and exhibit one‐dimension neutral structure, in which H2L effectively functions as a bridging ligand and give rise to a chain‐like polymer. The luminescent properties of polymers in solid state and in solution were investigated and 1 exhibits typical red luminescence of EuIII ions in solid state and dichloromethane solution and 2 emits the ligand‐centered blue luminescence. The energy transfer mechanisms in these luminescent lanthanide polymers were described through calculation of the lowest triplet level of ligand H2L. 相似文献
3.
Lu Huang Yu Zhang Zhong-Yi Liu Xiu-Guang Wang Xiao-Jun Zhao En-Cui Yang 《无机化学与普通化学杂志》2020,646(5):282-287
Two N'-(2-hydroxybenzylidene)pyridine N-oxide-carbohydrazide (H3L)-based coordination complexes with the formula [Ln2(DMF)2(OAc)2(HL)2]n (Ln = Dy for 1 and Eu for 2 ) were solvothermally synthesized. Crystal structures, thermal stabilities, magnetic and luminescent properties of the two complexes were fully investigated. Both complexes are isomorphic two-dimensional layers with centrosymmetric {Ln2} subunits extended by doubly deprotonated HL2– connectors. Complex 1 with highly anisotropic DyIII spin exhibits slightly frequency-dependent magnetic relaxations under zero dc field with an effective energy barrier of ca. 6.84 K. EuIII-based complex 2 displays only one weak fluorescent emission around 532 nm with the absence of characteristic emission of EuIII ion. These results provide helpful hints of the hydrazide Schiff-functionalized organic ligands on the function modulations of the resulting Ln complexes. 相似文献
4.
Synthesis,Crystal Structure,Fluorescent and Antioxidation Properties of Cerium(III) and Europium(III) Complexes with Bis(3‐methoxysalicylidene)‐3‐oxapentane‐1,5‐diamine
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Two aliphatic ether Schiff base lanthanide complexes (Ln = Eu, Ce) with bis(3‐methoxysalicylidene)‐3‐oxapentane‐1,5‐diamine (Bod), were synthesized and characterized by physicochemical and spectroscopic methods. [Eu(Bod)(NO3)3] ( 1 ) is a discrete mononuclear species and [Ce(Bod)(NO3)3DMF]∞ ( 2 ) exhibits an inorganic coordination polymer. In the two complexes, the metal ions both are ten‐coordinated and the geometric structure around the LnIII atom can be described as distorted hexadecahedron. Under excitation at room temperature, the red shift in the fluorescence band of the ligand in the complexes compared with that of the free ligand can be attributed to coordination of the rare earth ions to the ligand. Moreover, the antioxidant activities of the two complexes were investigated. The results demonstrated that the complexes have better scavenging activity than both the ligand and the usual antioxidants on the hydroxyl and superoxide radicals. 相似文献
5.
Synthesis, Crystal Structure, and Thermal Decomposition of Mg(H2O)6[B12H12] · 6 H2O By reaction of an aqueous solution of the free acid (H3O)2[B12H12] with MgCO3 and subsequent isothermic evaporation of the resulting solution to dryness, colourless, bead‐shaped single crystals of the dodecahydrate of magnesium dodecahydro closo‐dodecaborate Mg(H2O)6[B12H12] · 6 H2O (cubic, F4132; a = 1643.21(9) pm, Z = 8) emerge. The crystal structure is best described as a NaTl‐type arrangement in which the centers of gravity of the quasi‐icosahedral [B12H12]2— anions (d(B—B) = 178—180 pm, d(B—H) = 109 pm) occupy the positions of Tl— while the Mg2+ cations occupy the Na+ positions. A direct coordinative influence of the [B12H12]2— units at the Mg2+ cations is however not noticeable. The latter are octahedrally coordinated by six water molecules forming isolated hexaaqua complex cations [Mg(H2O)6]2+ (d(Mg—O) = 206 pm, 6×). In addition, six “zeolitic” water molecules are located in the crystal structure for the formation of a strong O—Hδ+···δ—O‐hydrogen bridge‐bonding system. The evidence of weak B—Hδ—···δ+H—O‐hydrogen bonds between water molecules and anionic [B12H12]2— clusters is also considered. Investigations on the dodecahydrate Mg[B12H12] · 12 H2O (≡ Mg(H2O)6[B12H12] · 6 H2O) by DTA/TG measurements showed that its dehydration takes place in two steps within a temperature range of 71 and 76 °C as well as at 202 °C, respectively. Thermal treatment eventually leads to the anhydrous magnesium dodecahydro closo‐dodecaborate Mg[B12H12]. 相似文献
6.
Andrew L. Hector William Levason Mark E. Light Gillian Reid Kripasindhu Sardar Wenjian Zhang 《无机化学与普通化学杂志》2013,639(6):906-910
Crystalline CrOCl3 contains [Cl2OCr(μ‐Cl)2CrOCl2] molecules with two square pyramidal CrOCl4 units sharing a common edge and with the Cr–O arranged anti, a new structure type for transition metal MOX3 compounds. Crystals are monoclinic with space group P21/c, Z = 4, with a = 5.735(5), b = 13.738(7), c = 11.318(4) Å, α = 90°, β = 98.346(6)°, γ = 90°. Its IR and UV/Vis spectra are reported and compared with those of the C3v monomer found in the gas phase. Structures are also reported for M2[CrOCl5] (M = Cs or Rb) and show a pseudo‐octahedral anion. Cs2[CrOCl5] adopts a K2PtCl6‐type structure with [CrOCl5]2– ions randomly orientated, but Rb2[CrOCl5] is orthorhombic with space group Pnma with a = 13.6471(7), b = 9.9175(5), and c = 6.9562(4) Å. Rietveld refinement of the data on the rubidium salt gave Cr–O = 1.628(1), Cr–CltransO = 2.652(7), Cr–CltransCl = 2.239(8)–2.342(3) Å. Corresponding CrV oxide bromide species do not form. 相似文献
7.
Two new mononuclear lanthanide(III) complexes Ln(pytz)3(H2O)3·(H2O)3.5[Ln=Tb(1); Eu(2); Hpytz= 5-(2-pyridyl)tetrazole] were synthesized by reacting Hpytz with the corresponding lanthanide(III) ions and characterized. The single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are isostructural and the lanthanide(III) ions in both complexes 1 and 2 are nine-coordinated, with three oxygen atoms of three coordination water molecules and six nitrogen atoms of three pytz ligands, forming a monocapped square antiprism. Extensive hydrogen bonds exist, resulting in a three-dimensional supramolecular network structure by hydrogen-bonds in both complexes 1 and 2, respectively. Complex 1 exhibits typical green fluorescence of Tb(III) ion and complex 2 red fluorescence of Eu(III) ion, in solid state at room temperature. 相似文献
8.
Lanthanide Complexes with 2,3‐Dimethoxybenzoic Acid and Terpyridine: Crystal Structures,Thermal Properties,and Antibacterial Activities
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The lanthanide coordination complexes Er(2,3‐DMOBA)3(terpy)(H2O) ( 1 ) and [Nd(2,3‐DMOBA)3(terpy)(H2O)]2 ( 2 ) (2,3‐DMOBA = 2,3‐dimethoxybenzoate; terpy = 2,2′:6′,2′′‐terpyridine) were synthesized and characterized by IR spectroscopy, powder X‐ray diffraction (XRD), single‐crystal X‐ray diffraction, and thermogravimetric analysis. Complex 1 crystallizes in the triclinic system, space group P1, and the mononuclear subunits form a 1D chain structure along the a axis by hydrogen bonds. Complex 2 crystallizes in the monoclinic system, space group P21/c, and the dinuclear subunits are further linked via the offset face‐to‐face π ··· π weak stacking interactions to form a supramolecular 2D layered structure. Thermal analysis showed that the complexes have three decomposition steps. The first step is the loss of coordination water molecules. The neutral terpy ligands and partial 2,3‐DMOBA ligands are lost in the second step. The remaining 2,3‐DMOBA ligands are lost in the third step. The 3D stacked plots for the FT‐IR spectra of the evolved gases are recorded and the gaseous products are identified by the typical IR spectra obtained at different temperatures from the 3D stacked plots. Meanwhile, the results of the antibacterial action tests show that 1 and 2 have better antibacterial activities to Candida albicans than to Escherichia coli or Staphylococcus aureus. In addition, complex 2 has better antibacterial action to Candida albicans than complex 1 . 相似文献
9.
Cheng‐Lin Wang Jing Li Prof. Dr. Zhen‐Gang Sun Rui‐Nian Hua Yan‐Yu Zhu Kai Chen Cheng‐Qi Jiao Chao Li Ming‐Jing Zheng Wei Chu Hui Tian Shou‐Hui Sun 《无机化学与普通化学杂志》2012,638(1):111-115
Five new lanthanide(III) diphosphonates, namely, Ln[(HL)(H2O)] · H2O [Ln = La ( 1 ), Ce ( 2 ), Pr ( 3 ), Nd ( 4 ), Sm ( 5 ); H4L = C6H11N(CH2PO3H2)2] were synthesized under hydrothermal reaction conditions at 140 °C and structurally characterized by X‐ray single‐crystal diffraction, X‐ray powder diffraction, IR spectroscopy, elemental, and thermogravimetric analysis. Compounds 1 – 5 are isostructural and exhibit a 2D framework structure. The LnO8 polyhedra form 1D zigzag chains along the c axis by edge‐sharing, which are further interconnected by CPO3 tetrahedra through edge‐ and corner‐sharing to form a 2D layer in the ac plane. The cyclohexyl groups of the ligands are orientated toward the interlayer space. 相似文献
10.
Investigations on the Crystal Structure of Lithium Dodecahydro‐closo‐dodecaborate from Aqueous Solution: Li2(H2O)7[B12H12] By neutralization of an aqueous solution of the acid (H3O)2[B12H12] with lithium hydroxide (LiOH) and subsequent isothermic evaporation of the resulting solution to dryness, it was possible to obtain the heptahydrate of lithium dodecahydro‐closo‐dodecaborate Li2[B12H12] · 7 H2O (≡ Li2(H2O)7[B12H12]). Its structure has been determined from X‐ray single crystal data at room temperature. The compound crystallizes as colourless, lath‐shaped, deliquescent crystals in the orthorhombic space group Cmcm with the lattice constants a = 1215.18(7), b = 934.31(5), c = 1444.03(9) pm and four formula units in the unit cell. The crystal structure of Li2(H2O)7[B12H12] can not be described as a simple AB2‐structure type. Instead it forms a layer‐like structure analogous to the well‐known barium compound Ba(H2O)6[B12H12]. Characteristic feature is the formation of isolated cation pairs [Li2(H2O)7]2+ in which the water molecules form two [Li(H2O)4]+ tetrahedra with eclipsed conformation, linked to a dimer via a common corner. The bridging oxygen atom (∢(Li‐ O ‐Li) = 112°) thereby formally substitutes Ba2+ in Ba(H2O)6[B12H12] according to (H2 O )Li2(H2O)6[B12H12]. A direct coordinative influence of the [B12H12]2— cluster anions to the Li+ cations is not noticeable, however. The positions of the hydrogen atoms of both the water molecules and the [B12H12]2— units have all been localized. In addition, the formation of B‐Hδ—···δ+H‐O‐hydrogen bonds between the water molecules and the hydrogen atoms from the anionic [B12H12]2— clusters is considered and their range and strength is discussed. The dehydratation of the heptahydrate has been investigated by DTA‐TG measurements and shown to take place in two steps at 56 and 151 °C, respectively. Thermal treatment leads to the anhydrous lithium dodecahydro‐closo‐dodecaborate Li2[B12H12], eventually. 相似文献
11.
TG, DTA and other analytical methods were applied to investigate the thermal behaviour and structures of the compounds Mg(ClAc)2(Py)2·2H2O (I), Mg(Cl2Ac)2(Py)·H2O (II), Mg(Cl3Ac)2(Py)·6H2O (III) and Mg(SCN)2(Py)3·2H2O (IV), where ClAc=ClCH2COO−, Cl2Ac=Cl2CHCOO−, Cl3Ac=Cl3CCOO− and Py=Pyridine. The compositions of the complexes and the solid-state intermediates and products of thermolysis were identified
by means of elemental analysis. Possible schemes of destruction of the complexes are suggested. The final products of the
thermal decompositions were MgO (I–III) and MgS (IV). The IR data suggest unidentate coordination of the carboxylate ions
to Mg(II) in complexes I–III. Py is coordinated to the Mg(II) through the nitrogen atom of its heterocyclic ring.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
13.
The new octadecanuclear Cu‐Ln complex, [Cu12Nd6(OH)24(betaine)16(NO3)3(H2O)10](NO3)[PF6]14·5H2O, was synthesized, which crystallizes in triclinic P1¯ space group, a = 18.649(6)Å, b = 20.363(7)Å, c = 19.865(7)Å, α = 116.61(2)°, β = 91.99(2)°, γ = 117.93(2)°, V = 5666(3)Å3. Its crystal structure features a [Cu12Nd6(OH)24(betaine)16(NO3)3(H2O)10]15+ core of pseudocubic Oh symmetry, with the six Nd ions positioned at the vertices of a regular octahedron and the twelve Cu ions located at the midpoints of the twelve octahedral edges. The Cu‐Nd metal framework may be viewed as a cuboctahedron, which is interconnected by twenty‐four μ3‐OH bridges that are each linked to one Nd ion and two Cu ions. In the centre of metal polyhedron, there is an encapsulated NO3— anion that exhibits a multi‐ coordinating mode. 相似文献
14.
Dariusz Wyrzykowski Rafał Kruszyński Tomasz Maniecki Zygmunt Warnke Dr. 《无机化学与普通化学杂志》2007,633(2):285-289
Two new tetrachloroferrates(III) have been synthesized of molecular formulas [(CH3)2NH2][FeCl4] and [(CH3)2NH2]2FeCl5. The differences in their physicochemical properties have been highlighted using thermal analysis (TG‐MS) and differential scanning calorimetry (DSC). The crystal and molecular structure of [(CH3)2NH]2FeCl5 was determined. The iron(III) cation is four coordinated by chloride ions, and it adopts a slightly distorted tetrahedral coordination with three angles smaller and three larger than the tetrahedral one. In the structure four intermolecular N‐H···Cl hydrogen bonds link the [(CH3)2NH2]+ cations to dimers via a Cl? bridge. 相似文献
15.
16.
The reactions of transition metal salts with taurine 5‐chlorosalicylaldelyde Schiff base gave two complexes [Ni(TCSSB)(H2O)3].H2O (1) and [Cu(TCSSB)(H2O)2]2[Cu(TCSSB)2].6H2O (2) (TCSSB=taurine‐5‐chlorosalicylaldelyde Schiff base), which were characterized by elemental analysis and X‐ray diffraction analysis. The complex 1 crystallized in monoclinic system with space group P2 1/c, and a=1.4816(2) nm, b=1.3953(2) nm, c= 0.7466(1) nm, β= 100.499(3)°, V=1.5176(4) nm3, Z=4, and an infinite 3‐D network structure was formed by hydrogen bonds among sulfo group, crystal water and coordinated water. Complex 2 crystallized in triclinic system with space group P1 , with the cell parameters: a = 0.6413(2) nm, b= 1.4596(3) nm, c= 1.6188(4) nm, a= 102.473(5)°, β= 98.979(4)°, γ=101.739°, V=1.4165(6) nm3, Z=1. The coordination environment between Cu(1) and Cu(2) is different. Cu(1) is slightly distorted square pyramidal while Cu(2) is distorted square‐plane. The complex 1 is mononuclear while the complex 2 is made up of two coordinated subunits, namely [Cu(TCSSB)2] and [CU(TCSSB)(H2O)2]2. Besides that the TG‐DTG of the complex 1 was analyzed, the thermal decomposition reaction of the complex was studied under a non‐isothermal condition by TG‐DTG. The TG and DTG curves indicate that the complex was decomposed in three stages: . 相似文献
17.
Huilu Wu Yuchen Bai Yanhui Zhang Guolong Pan Jin Kong Furong Shi Xiaoli Wang 《无机化学与普通化学杂志》2014,640(10):2062-2071
The Schiff base N,N′‐bis(salicylidene)‐1,5‐diamino‐3‐oxapentane (H2L) and its lanthanide(III) complexes, PrL(NO3)(DMF)(H2O) ( 1 ) and Ho2L2(NO3)2 · 2H2O ( 2 ), were synthesized and characterized by physicochemical and spectroscopic methods. Single crystal X‐ray structure analysis revealed that complex 1 is a discrete mononuclear species. The PrIII ion is nine‐coordinate, forming a distorted capped square antiprismatic arrangement. Complex 2 is a centrosymmetric dinuclear neutral entity in which the HoIII ion is eight‐coordinate with distorted square antiprismatic arrangement. The DNA‐binding properties of H2L and its LnIII complexes were investigated by spectrophotometric methods and viscosity measurements. The results suggest that the ligand H2L and its LnIII complexes both connect to DNA in a groove binding mode; the complexes bind more strongly to DNA than the ligand. Moreover, the antioxidant activities of the LnIII complexes were in vitro determined by superoxide and hydroxyl radical scavenging methods, which indicate that complexes 1 and 2 have OH · and O2– · radical scavenging activity. 相似文献
18.
从含4,4'-二吡啶胺结构单元的双(二吡啶胺) 桥联配体出发,采用溶剂热法合成了两个结构新颖的配位聚合物:[CdL1Br2]n?7.5nH2O (L1 = N,N,N′,N′-四(4-吡啶)-1,4-苯二胺) (1)和[Cu2L2(μ1,1,3-SCN)2]n?nMeOH (L2 = N,N-二(2-吡啶)-N',N'-二(4-吡啶)-1,4-苯二胺) (2),对它们进行了元素分析、红外光谱等表征,并用X-射线单晶衍射测定了其晶体结构。单晶测试结果显示,配合物1中配体L1的四个吡啶N原子均参与配位,桥联了4个Cd原子,每个Cd原子与四个吡啶 N 原子和两个溴配位,形成六配位的八面体构型。通过这些配位作用,最终形成包含 Kagome 结构的三维超分子网络。配合物2 是由一维柱状 {Cu(SCN)}n 链通过 L2 桥联生成的二维结构。有趣的是,L2中具有螯合能力的2,2'-二吡啶胺单元并未参与配位,只有4,4'-二吡啶胺单元中的两个吡啶N原子分别与一个 Cu(I) 配位,连接了相邻两条平行的{Cu(SCN)}n 链,生成二维结构。 相似文献
19.
4‐Methylpyridinium cations, mpyH+, crystallized with complex aqua/chloro/lanthanoid(III) species for the gamut of the rare earth series, have ‘domains of existence’ defined for the following forms:
- (a) The triclinic series (mpyH)2[{(H2O)3Cl3Ln(μ‐Cl)(2|2)}2], previously defined for the Ln = La–Nd members (those for La, Pr characterized by full structure determinations);
- (b) The triclinic series (mpyH)2[(H2O)3LnCl4]Cl, previously defined for the Ln = Eu, Ho members by full structure determinations, is here augmented by the Ln = Nd, Sm examples (full structure determinations, the latter a new ‘light’ Ln extremum);
- (c) A new monoclinic C2/c series (mpyH)2[(H2O)4LnCl3]Cl2, defined for the Ln = Er–Yb extrema (full structural characterizations for the Ln = Er, Tm, Yb members); the lanthanoid‐containing entity (which, with the cations, exhibits some disorder) is a neutral molecule of a new type. For the Ln = Lu case, a fully ordered derivative monoclinic C2 form has been obtained in a cell one half the size.
- (i) For Ln = La, (mpyH)8[{(H2O)3Cl3La(μ‐Cl)(2|2)}2]‐[{(H2O)4Cl2La(μ‐Cl)2La(OH2)2Cl2(μ‐Cl)(2|2)}2]Cl4·6H2O·mpy has been defined by a full structural determination; the binuclear anion is similar to that in (a), albeit with some disorder, with the tetranuclear anion derivative of it.
- (ii) For Ln = Lu, (mpyH)2[(H2O)5LuCl2]Cl3 is defined by a full structure determination.
- (iii) For Ln = Y, (mpyH)2[(H2O)7YCl]Cl4 is defined by a full structure determination; here, and in (ii), the complex component is cationic.
20.
在水-乙醇混合体系中, 将浓硝酸硝化的Sm2O3与1,10-邻菲啰啉反应, 用冰醋酸调节pH≈4, 形成醋酸根桥联的双核钐配合物[Sm2(CH3COO)4(NO3)2(phen)2](phen=1,10-邻菲啰啉), 用元素分析、红外光谱和核磁共振谱等进行了表征, 并用X射线衍射测定了配合物的晶体结构, 此外, 对配合物进行了非等温热分解动力学研究. 该晶体属于三斜晶系, P1空间 群, 晶胞参数a=0.979 6(3) nm, b=0.981 3(4) nm, c=1.127 3(4) nm, α=106.666(5)°, β=113.034(5)°, γ=102.656(5)°, V=0.885 4(5) nm3, Z=1, μ=3.361 mm-1, Dc=1.915 g/cm3, F(000)=498, R1=0.059 6, wR2=0.144 8. 该配合物是双核分子, 2个Sm(Ⅲ)离子通过4个醋酸根的羧基桥联, 每个中心离子分别与周围5个来自羧基的桥氧原子、 一个硝酸根的两个氧原子和一个邻菲啰啉分子中的两个氮原子配位, 形成九配位扭曲多面体. 非等温热分解动力学研究结果表明, 配合物第一步热分解反应可能为二级反应, 其动力学方程为dα/dT=A/[βe-E/RT(1-α)2], 分解反应的表观活化能为344.84 kJ/mol, 指前因子lnA=66.52. 相似文献