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1.
The product from reaction of lanthanum chloride heptahydrate with salicylic acid and thioproline, [La(Hsal)2•(tch)]•2H2O, was synthesized and characterized by IR, elemental analysis, molar conductance, thermogravimatric analysis and chemistry analysis. The standard molar enthalpies of solution of LaCl3•7H2O (s), [2C7H6O3 (s)], C4H7NO2S (s) and [La(Hsal)2•(tch)]•2H2O (s) in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide (DMSO) and 3 mol•L-1 HCl were determined by calorimetry to be [LaCl3•7H2O (s), 298.15 K]=(-102.36±0.66) kJ•mol-1, [2C7H6O3 (s), 298.15 K]=(26.65±0.22) kJ•mol-1, [C4H7NO2S (s), 298.15 K]=(-21.79±0.35) kJ•mol-1 and {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}=(-41.10±0.32) kJ•mol-1. The enthalpy change of the reaction LaCl3•7H2O (s)+2C7H6O3 (s)+C4H7NO2S (s)=[La(Hsal)2•(tch)]•2H2O (s)+3HCl (g)+5H2O (l) (Eq. 1) was determined to be =(41.02±0.85) kJ•mol-1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of [La(Hsal)2•(tch)]•2H2O (s) was estimated to be {[La(Hsal)2•(tch)]•2H2O (s), 298.15 K}=(-3017.0±3.7) kJ•mol-1.  相似文献   

2.
The CaCl2-(NH4)2HPO4-NH4HCO3-(C6H11NO4) n -H2O system at 25°C has been investigated by the solubility (Tananaev’s residual concentration) method and pH measurements. Coprecipitation conditions have been determined for nanocrystalline type A and B calcium carbonate apatites. Type A: Ca10(PO4)6(CO3) x (OH)2 − 2x · yC6H11NO4 · zH2O (x = 0.2, 0.5, 1.0; y = 0.1, 0.3, 0.5; z = 5.3−6.7); type B: Ca10[(PO4)5.7(CO3)0.45]CO3 · 0.3C6H11NO4 · 9H2O, and Ca10[(PO4)5.55(CO3)0.675]CO3 · 0.3C6H11NO4 · 9.2H2O. The solid phases have been characterized by chemical analysis, X-ray diffraction, thermogravimetric analysis, and IR spectroscopy.  相似文献   

3.
The deterioration of zinc, zinc—calcium and manganese phosphate coatings and oxalate coatings on steel on heating was investigated by conversion electron Mössbauer spectrometry. and the chemical change of the coatings was analysed on the basis of the thermal characteristics of Zn3(PO4)2·4H2O, Zn2Fe(PO4)4·4H2O, CaZn2(PO4)2·2H2O, Fe3(PO4)2·8H2O. (Mn, Fe)5H2(PO4)4·4H2O and FeC2O4·2H2O. The steel substrate beneath the coatings influenced the thermal decomposition and evaporation of coating materials under the various heating atmospheres. The heat resistance of these coatings and the state of the substrate were also investigated.  相似文献   

4.
The self‐assembly reactions of transition metal ions and 1,3,5‐benzenetricarboxylic acid (H3btc) in the presence of auxiliary aromatic bidentate ligands 1,10‐phenanthroline (1,10‐phen) or 4,4′‐bipyridine‐N,N′‐dioxide (4,4′‐bpdo) have isolated four coordination polymers [Co18(btc)10(H2O)6(OH)6(1,10‐phen)6] · 14H2O · 3DMF ( 1 ) and [M3(btc)2(H2O)4(4,4′‐bpdo)] · 2H2O · 2DMF [M = Co ( 2 ), Mn ( 3 ), Ni ( 4 )]. Single‐crystal X‐ray diffraction analysis revealed that the M3 clusters in the structure of 1 – 4 are connected by hydroxyl group oxygen atoms (or oxygen atoms from 4,4′‐bpdo ligands) and carboxyl groups to generate a three‐dimensional framework. The network of final assemblies can be adjusted by varying the type of auxiliary ligands (1,10‐phen, 4,4′‐bpdo). In addition, the gas adsorption properties of 2 are also investigated.  相似文献   

5.
以1,1′-二羟基-5,5′-联四唑(H_2BTO)为配体,镧系金属离子作为金属中心,采用溶剂热法制备了5种金属配合物:[La_2(BTO)_3(H_2O)_8]·2H_2O (1)、[Ce_2(BTO)_3(H_2O)_8]·2H_2O (2)、[Pr_2(BTO)_3(H_2O)_8]·2H_2O (3)、[Sm_2(BTO)_3(H_2O)_8]·2H_2O (4)和[Nd_2(BTO)_3(DMF)_4]·6H_2O (5)。通过单晶X射线衍射和元素分析对5种配合物的结构进行了表征。结果表明,5种配合物均属于单斜晶系,P2_1/n空间群。利用差示扫描量热法研究了配合物1~4的热稳定性,采用Kissinger法和Ozawa法分别计算了其热分解动力学参数。  相似文献   

6.
Three complexes, Na4[DyIII(dtpa)(H2O)]2?·?16H2O, Na[DyIII(edta)(H2O)3]?·?3.25H2O and Na3[DyIII (nta)2(H2O)]?·?5.5H2O, have been synthesized in aqueous solution and characterized by FT–IR, elemental analyses, TG–DTA and single-crystal X-ray diffraction. Na4[DyIII(dtpa)(H2O)]2?·?16H2O crystallizes in the monoclinic system with P21/n space group, a?=?18.158(10)?Å, b?=?14.968(9)?Å, c?=?20.769(12)?Å, β?=?108.552(9)°, V?=?5351(5)?Å3, Z?=?4, M?=?1517.87?g?mol?1, D c?=?1.879?g?cm?3, μ?=?2.914?mm?1, F(000)?=?3032, and its structure is refined to R 1(F)?=?0.0500 for 9384 observed reflections [I?>?2σ(I)]. Na[DyIII(edta)(H2O)3]?·?3.25H2O crystallizes in the orthorhombic system with Fdd2 space group, a?=?19.338(7)?Å, b?=?35.378(13)?Å, c?=?12.137(5)?Å, β?=?90°, V?=?8303(5)?Å3, Z?=?16, M?=?586.31?g?mol?1, D c?=?1.876?g?cm?3, μ?=?3.690?mm?1, F(000)?=?4632, and its structure is refined to R 1(F)?=?0.0307 for 4027 observed reflections [I?>?2σ(I)]. Na3[DyIII(nta)2(H2O)]?·?5.5H2O crystallizes in the orthorhombic system with Pccn space group, a?=?15.964(12)?Å, b?=?19.665(15)?Å, c?=?14.552(11)?Å, β?=?90°, V?=?4568(6)?Å3, Z?=?8, M?=?724.81?g?mol?1, D c?=?2.102?g?cm?3, μ?=?3.422?mm?1, F(000)?=?2848, and its structure is refined to R 1(F)?=?0.0449 for 4033 observed reflections [I?>?2?σ(I)]. The coordination polyhedra are tricapped trigonal prism for Na4[DyIII(dtpa)(H2O)]2?·?16H2O and Na3[DyIII(nta)2(H2O)]?·?5.5H2O, but monocapped square antiprism for Na[DyIII(edta)(H2O)3]?·?3.25H2O. The crystal structures of these three complexes are completely different from one another. The three-dimensional geometries of three polymers are 3-D layer-shaped structure for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 1-D zigzag type structure for Na[DyIII(edta)(H2O)3]?·?3.25H2O and a 2-D parallelogram for Na3[DyIII(nta)2(H2O)]?·?5.5H2O. According to thermal analyses, the collapsing temperatures are 356°C for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 371°C for Na[DyIII(edta)(H2O)3]?·?3.25H2O and 387°C for Na3[DyIII(nta)2(H2O)]?·?5.5H2O, which indicates that their crystal structures are very stable.  相似文献   

7.
A series of transition metal (Zn, Cu, Mn) complexes with chelidamic acid (2,6-dicarboxy-4-hydroxypyridine, H3CAM) and 4,4′-bipyridine (bipy), [Zn2(bipy)Cl2] n (1), {[Zn2(HCAM)(H2CAM)2]?·?(bipy)?·?3.5H2O} n (2), [Mn3(HCAM)3(H2O)7]?·?(bipy)?·?3H2O (3), [Mn2(HCAM)2(bipy)?·?(H2O)2]?·?4H2O (4), [Cu2(HCAM)2(bipy)?·?(H2O)2]?·?4H2O (5), and Cu2(HCAM)2(bipy)?·?(H2O)2 (6), have been synthesized by hydrothermal or solution methods and characterized by single-crystal X-ray diffraction. The structural analyses reveal that 1 exhibits a zigzag chain of Zn(II), Cl?, and 4,4′-bipyridine. In 2, a 1-D polymeric [Zn2(HCAM)(H2CAM)2] n chain and a discrete 4,4′-bipyridine assemble into a 2-D supramolecular network via H-bonds. Complex 3 consists of asymmetric units of Mn3(HCAM)3(H2O)7 that are linked by hydrogen bonds to form a 2-D H-bonded network. Complexes 46 are isomorphous and possess discrete structures. The photoluminescent properties of 16 at room temperature were studied.  相似文献   

8.
Two new complexes of the Ln2(oda)3·nH2O (oda =–O2CCH2OCH2CO2–) series are reported, i.e. {[Pr2(C4H4O5)3(H2O)3]·5H2O}n and {[Nd2(C4H4O5)3(H2O)6]·C4H6O5·‐2H2O}n. The former is isostructural with the reported La analogue, while the latter is a new structural variety within the series. Each compound exhibits two independent nine‐coordinated Ln centres showing a variety of coordination geometries.  相似文献   

9.
Reactions of a freshly prepared Zn(OH)2‐2x(CO3)x · yH2O precipitate, phenanthroline with azelaic and sebacic acid in CH3OH/H2O afforded [Zn(phen)(C9H15O4)2] ( 1 ) and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O ( 2 ), respectively. They were structurally characterized by X‐ray diffraction methods. Compound 1 consists of complex molecules [Zn(phen)(C9H15O4)2] in which the Zn atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different monodentate hydrogen azelaato groups. Intermolecular C(alkyl)‐H···π interactions and the intermolecular C(aryl)‐H···O and O‐H···O hydrogen bonds are responsible for the supramolecular assembly of the [Zn(phen)(C9H15O4)2] complexes. Compound 2 is built up from crystal H2O molecules and the centrosymmetric binuclear [Zn2(phen)2(H2O)2(C10H16O4)2] complex, in which two [Zn(phen)(H2O)]2+ moieties are bridged by two sebacato ligands. Through the intermolecular C(alkyl)‐H···O hydrogen bonds and π‐π stacking interactions, the binuclear complex molecules are assembled into layers, between which the lattice H2O molecules are sandwiched. Crystal data: ( 1 ) C2/c (no. 15), a = 13.887(2), b = 9.790(2), c = 22.887(3)Å, β = 107.05(1)°, U = 2974.8(8)Å3, Z = 4; ( 2 ) P1¯ (no. 2), a = 8.414(1), b = 10.679(1), c = 14.076(2)Å, α = 106.52(1)°, β = 91.56(1)°, γ = 99.09(1)°, U = 1193.9(2)Å3, Z = 1.  相似文献   

10.
Hydrogen conformations in [Ta6Br12(H2O)6]X2 · trans — [Ta6Br12(OH)4(H2O)2] · 18H2O (X = Cl or Br), [Ta6Br12(H2O)6]8 · (ZnBr4)8 · 96H2O, Na6[RuO2{TeO4(OH)2}2] · 16H2O, and Na5[Ag{TeO4(OH)2}2] · 16H2O were modeled from a set of simple rules. The systems are quite complex, but subsequent energy optimizations show that it is possible to make quite good predictions of where the hydrogen atoms are situated.  相似文献   

11.
Five lanthanide(III) coordination polymers with 2-methyl-1H-imidazole-4,5-dicarboxylic acid (H3MIDC) and ammonium oxalate, {[(Ln1)2(HMIDC)2(C2O4)(H2O)3]?·?3H2O} n (Ln1?=?Nd (1), Sm (2)), {[Eu2(HMIDC)2(C2O4)(H2O)3]?·?0.5EtOH?·?3H2O} n (3), {[Ce2(HMIDC)2(C2O4)(H2O)3]?·?EtOH?·?3H2O} n (4), and {[Gd2(HMIDC)2(C2O4)(H2O)3]?·?MeOH?·?3H2O} n (5), have been prepared and structurally characterized. Single-crystal X-ray diffraction analyses reveal that 1 and 2 are isostructural, as are 3, 4, and 5. Each exhibits a 3-D open framework, which is built by a regular 2-D grid connected by HMIDC2? and Ln(III). The luminescence and thermal properties of these complexes have been investigated as well.  相似文献   

12.
The solid-state coordination reaction: Nd(NO3)3·6H2O(s)+4Ala(s) → Nd(Ala)4(NO3)3·H2O(s)+5H2O(l) and Er(NO3)3·6H2O(s)+4Ala(s) → Er(Ala)4(NO3)3·H2O(s)+5H2O(l) have been studied by classical solution calorimetry. The molar dissolution enthalpies of the reactants and the products in 2 mol L–1 HCl solvent of these two solid-solid coordination reactions have been measured using a calorimeter. From the results and other auxiliary quantities, the standard molar formation enthalpies of [Nd(Ala)4(NO3)3·H2O, s, 298.2 K] and[Er(Ala)4(NO3)3·H2O, s,298.2 K] at 298.2 K have been determined to be Δf H m 0 [Nd(Ala)4(NO3)3·H2O,s, 298.2 K]=–3867.2 kJ mol–1, and Δf H m 0 [Er(Ala)4(NO3)3·H2O, s, 298.2 K]=–3821.5 kJ mol–1. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
V2O3(OH)4(g), Proof of Existence, Thermochemical Characterization, and Chemical Vapor Transport Calculations for V2O5(s) in the Presence of Water By use of the Knudsen-cell mass spectrometry the existence of V2O3(OH)4(g) is shown. For the molecules V2O3(OH)4(g), V4O10(g), and V4O8(g) thermodynamic properties were calculated by known Literatur data. The influence of V2O3(OH)4(g) for chemical vapor transport reactions of V2O5(s) with water ist discussed. ΔBH°(V2O3(OH)4(g), 298) = –1920 kJ · mol–1 and S°(V2O3(OH)4(g), 298) = 557 J · K–1 · mol–1, ΔBH°(V4O10(g), 298) = –2865,6 kJ · mol–1 and S°(V4O10(g), 298) = 323.7 J · K–1 · mol–1, ΔBH°(V4O8(g), 298) = –2465 kJ · mol–1 and S°(V4O8(g), 298) = 360 J · K–1 · mol–1.  相似文献   

14.
A 3-D metal-organic framework [Cd3(L)2(DMF)2]?·?2H2O?·?2DMF (1) (H3L?=?2-(dimethylcarbamoyl)biphenyl-5,2′,5′-tricarboxylic acid, DMF?=?N,N-dimethylformamide) with trinuclear Cd(II) units has been prepared. Complex 1 is a (3,?6)-connected (42?·?6)2(44?·?62?·?88?·?10) coordination net, which results from the solvothermal in situ formation of a new asymmetric ligand, 2-(dimethylcarbamoyl)biphenyl-5,2′,5′-tricarboxylic acid (H3L), through amidation of biphenyl-2,5,2′,5′-tetracarboxylic acid (H4bptc). Additionally, the luminescence of 1 has been investigated.  相似文献   

15.
The title complex {[Co(dimb)2(H2O)2]·(NO3)2·(H2O)2}n ( 1 ) (dimb = 1,3‐di(imidazol‐1‐ylmethyl)‐5‐methylbenzene) has been hydrothermally synthesized by the reaction of dimb with Co(NO3)2·6H2O in aqueous solution. The cobalt(II) atoms are linked by bridging dimb ligands to form 2D corrugated and wavy networks containing Co4(dimb)4 macrocyclic motifs. Two neighboring independent layers interlinked each other in a parallel fashion to construct three‐dimensional structure by O–H···O, N–H···O and C–H···O hydrogen bonds. Magnetic measurement shows the weak antiferromagnetic interaction with a one‐dimensional chain model in the range of 5–300 K, with J of –0.68 cm−1.  相似文献   

16.
Interactions between the nucleotides: adenosine‐5′‐diphosphate (ADP) and adenosine‐5′‐triphosphate (ATP) with NiII and CoII ions, as well as with spermine (Spm) and 1,11‐diamine‐4,8‐diazaundecane (3,3,3‐tet) are the subject of this study. Composition and stability constants of mixed complexes thus formed have been determined on the basis of the potentiometric measurements, whereas interaction centres in ligands have been identified by VIS and NMR spectral parameter analysis. Mixed tetraprotonated complexes with NiII, i.e. Ni(ADP)H4(Spm), Ni(ATP)H4(Spm), Ni(ADP)H4(3,3,3‐tet) and Ni(ATP)H4(333‐tet), are identified as ML·······L′ type adducts, in which the main coordination centre is the nucleotide nitrogen N(1) or N(7) donor atom, and the fully protonated polyamine is engaged in noncovalent interactions with nucleotide phosphate group oxygen atoms. Ni(ADP)H2(Spm), Ni(ATP)H2(Spm), Ni(ADP)H2(3,3,3‐tet) and Ni(ATP)H2(3,3,3‐tet) complexes represent the {N3} coordination type In diprotonated mixed complexes of NiII with spermine are weak noncovalent interligand interactions, providing an additional stabilising effect. Formation of ML·······L′ type molecular complexes has been observed in systems with CoII: Co(ADP)H4(Spm), Co(ATP)H4(Spm), Co(ADP)H4(3,3,3‐tet) and Co(ATP)H4(3,3,3‐tet), in which the N(7) atom and oxygen atoms of the phosphate group are involved in coordination and the fully protonated polyamine is engaged in noncovalent interactions with the nucleotide N(1).  相似文献   

17.
Five complexes [Co3(Hpmad)6]·(4‐sb)2·(CH3COO)2·(H2O)2 ( 1 ), [Co3(Hpmad)6]·(3‐sb)2·(CH3COO)2·(H2O)0.5 ( 2 ), [Co(Hpmad)2(4‐sb)]n ( 3 ), [Co(Hpmad)2(3‐sb)]n ( 4 ) and {[Co(Hpmad)(SO4)(H2O)2]·H2O}n ( 5 ) [Hpmad is 2‐pyrimidineamidoxime, H2(4‐sb) is 4‐sulfobenzoic acid and H2(3‐sb) is 3‐sulfobenzoic acid], were prepared at room temperature. Complexes 1 – 5 were characterized by elemental analyses, single crystal X‐ray diffractions, powder X‐ray diffractions, infrared spectra, thermogravimetric analyses, fluorescence spectra and magnetic susceptibility measurements. Complexes 1 and 2 possess the linear trinuclear Co2+ structures. Complexes 3 and 4 exhibit similar one‐dimensional (1D) chains. Complex 5 comprises the 1D helical chain. The change of anion in cobalt salt from CH3COO? to Cl? to SO42? leads to the structural evolution from the linear trinuclear Co2+ structure to the 1D chain to the 1D helical chain. Complexes 1 – 5 exhibit the Hpmad‐based emissions. The magnetic properties of 1–5 were also investigated.  相似文献   

18.
Polyol Metal Complexes. 491) μ‐Dulcitolato‐O2, 3;4, 5 Complexes with CuII(en) and NiII(tren) Metal Fragments The dinuclear ethylenediamine‐copper(II) complex of the tetra‐anion of the achiral alditol dulcitol (galactitol) is remarkable, since it was the first crystalline carbohydrate—metal complex ever reported (W. Traube, G. Glaubitt, V. Schenck, Ber. Dtsch. Chem. Ges. 1930 , 63, 2083—2093). Although its existence is recognized for many decades, its structure remained unknown due to a kind of crystal packing that promotes twinning. Crystal growth at low temperatures now yielded crystalline specimens of [(en)2Cu2(Dulc2, 3, 4, 5H—4)] · 7 H2O ( 1 ) that have allowed us to unravel both the crystal structure and the twinning law. Closely related molecular structures are adopted by [(tren)2Ni2(Dulc2, 3, 4, 5H—4)] · 20 H2O ( 2 ) and [(Me3tren)2Ni2(Dulc2, 3, 4, 5H—4)] · 16 H2O ( 3 ), the latter showing the shortest hydrogen bond towards a polyolate acceptor ever found (O···O distance: 2.422Å).  相似文献   

19.
The reactions of Ln(NO3)3 · 6H2O and 4‐acetamidobenzoic acid (Haba) with 4,4′‐bipyridine (4,4′‐bpy) in ethanol solution resulted in three new lanthanide coordination polymers, namely {[Ln(aba)3(H2O)2] · 0.5(4,4′‐bpy) · 2H2O} [Ln = Sm ( 1 ), Gd ( 2 ), and Er ( 3 ), aba = 4‐acetamidobenzoate]. Compounds 1 – 3 are isomorphous and have one‐dimensional chains bridged by four aba anions. 4,4′‐Bipyridine molecules don’t take part in the coordination with LnIII ions and occur in the lattice as guest molecules. Moreover, the adjacent 1D chains in the complex are further linked through numerous N–H ··· O and O–H ··· O hydrogen bonds to form a 3D supramolecular network. In addition, complex 1 in the solid state shows characteristic emission in the visible region at room temperature.  相似文献   

20.
The coordinating properties of a new bis(pyridylhydrazone) ligand derived from iminodiacetic acid diethyl ester and 2-pyridinecarboxaldehyde (picolinaldehyde) H3Imdp and of the bis(salicylhydrazone) H5Imds and H4MeImds ligands derived, respectively, from iminodiacetic acid diethyl ester and from methyl-iminodiacetic acid diethyl ester and salicylaldehyde were considered, by means of analytical and spectroscopic methods, towards first row transition metal ions. These ligands showed various coordination modes in complexation with Cu(II), Co(II), Mn(II) and Zn(II) ions. In particular, we have synthesized and characterized, by analytical, 1H NMR and IR techniques, tri-, di- and mononuclear metal complexes of formula Co3(HImdp)(NO3)4·2H2O, Cu3(HImdp)(NO3)4·C2H5OH·H2O, Cu3(HImdp)Cl4, Zn2(H3Imdp)(ClO4)4·2H2O, Co3(HImds)Cl2·CH3OH·H2O, Zn2(H3Imds)Cl2·2H2O, Co(H4Imds)NO3·2H2O, Mn(H4Imds)Cl·CH3OH·H2O, Cu(H3Imds)·CH3OH·H2O and Cu(H2MeImds).CH3OH·3H2O. Antibacterial, antifungal and antiprotozoal properties of H5Imds and H3Imdp together with three copper(II) trinuclear species of H5Imds of formula Cu3(HImds)(NO3)2.2CH3OH·2H2O, Cu3(HImds)(ClO4)2.EtOH·2H2O and Cu3(HImds)SO4·4H2O are also discussed. The H5Imds ligand and their trinuclear copper(II) complexes showed good activities versus Trichomonas vaginalis, Staphylococcus epidermidis and Acanthamoeba castellanii.  相似文献   

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