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1.
The (enH2)[GdIII 2(pdta)2(H2O)2]?·?8H2O (1) (en?=?ethylenediamine and H4pdta?=?propylenediamine-N,?N,?N′,?N′-tetraacetic acid) and (enH2)[GdIII(egta)(H2O)]2?·?6H2O (2) (H4egta?=?ethyleneglycol-bis-(2-aminoethylether)-N,?N,?N′,?N′-tetraacetic acid) complexes were synthesized and characterized by infrared spectrum, thermal analysis, and single-crystal X-ray diffraction. The complex (enH2)[GdIII 2(pdta)2(H2O)2]?·?8H2O has a binuclear eight-coordinate structure with pseudo square antiprism and crystallizes in the monoclinic crystal system with C2/c space group. Through a carboxylate bridge, an infinite 1-D zigzag polymeric binuclear [GdIII 2(pdta)2(H2O)2]2? complex anion is formed. All infinite zigzag polymeric complex anions link through hydrogen bonds, yielding a layer structure. (enH2)[GdIII(egta)(H2O)]2?·?6H2O has a mononuclear nine-coordinate structure with pseudo monocapped square antiprism and crystallizes in the monoclinic crystal system with P21/n space group. Each enH2 2+ cation, through hydrogen bonds, connects two adjacent [GdIII(egta)(H2O)]? complex anions.  相似文献   

2.
3.
Two rare-earth metal coordination compounds, (NH4)4[SmIII2(Httha)2]·16H2O (1) (H6ttha?=?triethylenetetramine-N,N,N,N′′,N′′′,N′′′-hexaacetic acid) and (NH4)4[SmIII2(dtpa)2]·10H2O (2) (H5dtpa?=?diethylenetriamine-N,N,N,N′′,N′′-pentaacetic acid), have been synthesized through reflux and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction techniques. SmIII of (NH4)4[SmIII2(Httha)2]·16H2O (1) is nine-coordinate, forming tricapped trigonal prismatic coordination with three amine nitrogens and six oxygens, in which four oxygens are from one ttha and two from the other ttha. (NH4)4[SmIII2(Httha)2]·16H2O (1) crystallizes in the monoclinic crystal system with P2(1)/c space group. The crystal data are: a?=?13.9340(13) Å, b?=?22.890(3) Å, c?=?20.708(2) (14) Å, β?=?99.521(2)°, and V?=?6513.7(13) Å3. There are two –NH+– groups in the [SmIII2(Httha)2]4?. The polymeric (NH4)4[SmIII2(dtpa)2]·10H2O (2) also is nine-coordinate with tricapped trigonal prismatic conformation and crystallizes in the triclinic crystal system with P–1 space group. The cell dimensions are: a?=?9.8240(8) Å, b?=?10.0329(9) Å, c?=?13.0941(11) Å, β?=?77.1640(10)°, and V?=?1227.30(18) Å3. In (NH4)4[SmIII2(dtpa)2]·10H2O, there are two types of ammonium cations, which connect [SmIII2(dtpa)2]4? and lattice water through hydrogen bonds, leading to a 2-D ladder-like layer structure.  相似文献   

4.
The title complexes, Na[ErIII(Cydta)(H2O)2] · 5H2O (I) and Na2[SmIII(Cydta)][SmIII(Cydta)(H2O)3] · 11H2O (II) (Cydta is trans-1,2-cyclohexanediaminetetraacetic acid), are prepared and characterized using IR, elemental analyses, and single-crystal X-ray diffraction techniques. Crystal I belongs to triclinic system (space group P1), which has a mononuclear eight-coordinate slightly distorted square antiprismatic conformation. The crystal data are as follows: a = 8.371(12) Å, b = 9.952(14) Å, c = 14.74(2) Å, α = 88.32(2)°, β = 76.30(2)°, γ = 87.87(2)°, V = 1192(3) Å3, Z = 1, ρ = 1.835 g/cm3, μ = 3.612 mm?1, F(000) = 658, R = 0.0194, and wR = 0.0520 for 4130 observed reflections with I≥2σ(I). Crystal II belongs to monoclinic system (space group P21/n), which has the binuclear nine-coordinate structure with tricapped trigonal prismatic conformation for Sm(1) and the pseudomonocapped square antiprismatic conformation for Sm(2). The crystal data are as follows: a = 12.283(6) Å, b = 15.626(7) Å, c = 25.875(12) Å, β = 97.962(7)°, V = 4919(4) Å3, Z = 4, ρ = 1.717 g/cm3, μ = 2.476 mm?1, F(000) = 2536, R = 0.0781, and wR = 0.1745 for 8554 observed reflections with I ≥ 2σ(I).  相似文献   

5.
Two dysprosium coordination compounds, (mnH)2[DyIII(Httha)]·3H2O (1) (H6ttha?=?triethylenetetramine-N,N,N′,N″,N′′′,N′′′-hexaacetic acid and mn?=?methylamine) and (enH2)3[DyIII(ttha)]2·9H2O (2) (en?=?ethylenediamine), were synthesized through direct heating and characterized by elemental analysis, FT-IR, thermal analysis, and single-crystal X-ray diffraction. X-ray diffraction analysis displays that 1 is a mononuclear nine-coordinate complex with a pseudo-monocapped square antiprismatic conformation (MCSAP) crystallizing in the monoclinic crystal system with P2(1)/c space group. The crystal data are as follows: a?=?16.1363(19)?Å, b?=?13.9336(11)?Å, c?=?13.6619(14)?Å, β?=?102.2490(10)°, and V?=?3001.8(5)?Å3. There are two kinds of methylamine cation in 1. They connect [DyIII(Httha)]2?and crystal waters through hydrogen bonds, leading to formation of a 2-D ladder-like layer structure. The polymeric 2 also is a nine-coordinate structure with a pseudo-MCSAP crystallizing in the monoclinic crystal system with P2/c space group. The cell dimensions are: a?=?17.7801(16)?Å, b?=?9.7035(10)?Å, c?=?22.096(2)?Å, β?=?118.874(2)°, and V?=?3338.3(6)?Å3. In 2 there are also two types of ethylenediamine cations. One connects three adjacent [DyIII(ttha)]3? complex anions through hydrogen bonds and the other is symmetrical forming hydrogen bonds with two neighboring [DyIII(ttha)]3? complex anions. These hydrogen bonds result in formation of a 2-D ladder-like layer structure as well.  相似文献   

6.
Two title rare earth metal coordination compounds, (MnH)[GdIII(Edta)(H2O)3] · 4H2O (I) and (MnH)2[Gd 2 III (H2Ttha)2] · 4H2O (II), where Mn = methylamine, H4Edta = ethylenediamine-N,N,N′,N′-tetraacetic acid, H6Ttha = triethylenetetramine-N,N,N′,N″,N′″,N′″-hexaacetic acid), have been successfully synthesized through direct heating reflux and characterized by FT-IR spectroscopy, thermal analysis and single-crystal X-ray diffraction techniques. In complex I, the Gd3+ ion is nine-coordinated by an Edta ligand and three water molecules, yielding a pseudo-monocapped square antiprismatic (MC-SAP) conformation. Complex I crystallizes in the orthorhombic crystal system with space group Fdd2. The cell dimensions are as follows: a = 19.5207(17), b = 35.387(3), c = 12.5118(11) Å, and V = 8642.8(13) Å3. The central Gd3+ ion of II is also ninecoordinate, forming tricapped trigonal prismatic (TC-TP) conformation with three amine nitrogen atoms and six oxygen atoms. Complex II crystallizes in the monoclinic crystal system with P2/c space group. The crystal data are as follows: a = 14.4301(13), b = 11.2400(11), c = 17.7102(16) Å, β = 112.606(2)°, and V = 2651.8(4) Å3. There retain outer-protonated and inner-protonated carboxyl oxygen atoms in the [Gd 2 III (H2Ttha)2]2? complex anion. In II, there are only one type of methylamine cation (MnH+) as the counter ion, which connects [Gd 2 III (H2Ttha)2]2? complex anions and lattice water molecules through hydrogen bonds, leading to the formation of 2D ladder-like layer structure.  相似文献   

7.
Tian  F. Y.  Yang  F.  Jiang  X. Q.  Wu  Q.  Wang  J. 《Russian Journal of Coordination Chemistry》2017,43(7):481-490

Two novel rare earth metal coordination compounds, (MnH)4[Ho III2 (Dtpa)2] · 12H2O (I) (Mn = methylamine, H5Dtpa = diethylenetriamine-N,N,N′,N″,N″-pentaaceticacid) and {(MnH)[HoIII(Egta)] · 3H2O} n (II) (H4Egta = ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) have been successfully synthesized through direct heating reflux and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction techniques (CIF files CCDC nos. 890878 (I) and 1457061 (II)). Complex I shapes a binuclear nine-coordinate structure with distorted tricapped trigonal prismatic conformation and crystallizes in the triclinic crystal system with space group P1?. The central Ho3+ ion is coordinated by three nitrogens and six oxygens from two octadentate Dtpa ligands. The cell dimensions are as follows: a = 9.8420(10), b = 12.1319(13), c = 13.2931(15) Å, α = 89.223(2)°, β = 68.4280(10)°, γ = 72.1280(10)° and V = 1396.0(3) Å3. Complex II adopts a polynuclear nine-coordinate structure with pseudo-monocapped square antiprismatic conformation and crystallizes in the monoclinic crystal system with space group C2/c. The central Ho3+ ion is coordinated by two nitrogens and seven oxygens from two octadentate Egta ligands. The crystal data are as follows: a = 38.4755(13), b =13.5569(5), c = 8.7343(3) Å, β = 100.135(3)° and V = 4484.8(3) Å3.

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8.
Two novel complexes, (EnH2)1.5[HoIII(Ttha)] · 4.5H2O (I) (En = ethylenediamine and H6Ttha = triethylenetetramine-N,N,N′,N″,N?,N?-hexaacetic acid) and (EnH2)[HoIII(Egta)(H2O)]2 · 6H2O (II) (H4Egta = ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid), were synthesized and their crystal structures were determined by single crystal X-ray diffraction techniques. Complex I has a nine-coordinate mononuclear structure with distorted tricapped trigonal prismatic conformation and crystallizes in the monoclinic crystal system with P2/n space group. The crystal data are as follows: a = 17.7541(18), b = 9.6810(10), c = 22.166(2) Å, β = 118.913(2)°, and V = 3335.0(6) Å3. Complex II has a mononuclear nine-coordinate structure with pseudo-monocapped square antiprismatic conformation and crystallizes in the monoclinic crystal system with P21/n space group. The crystal data are as follows: a = 12.978(8), b = 12.685(8), c = 14.905(9) Å, β = 105.333(7)°, and V = 2366(2) Å3. In I, there are two types of EnH 2 2+ anions. They connect to [HoIII(Ttha)]3? by hydrogen bonds leading to the formation of 3D pore structure along z axis. In II, EnH 2 2+ cation connects three adjacent [HoIII(Egta)(H2O)]? complex anions through hydrogen bonds, these hydrogen bonds lead to the formation of 2D network structure in [101] plane. The results showed that ligand structures play a crucial role in crystal and molecular structure of their complexes. In addition, the protonated (EnH 2 2+ ) cations conjugating to [HoIII(Ttha)]3? and [HoIII(Egta)(H2O)]? complex anions are reviewed, which act as an important beginning for study of Ho(III) complexes conjugating with other various amino and heterocyclic biomolecule.  相似文献   

9.
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   

10.
Two lanthanide complexes, (mnH)2[EuIII(egta)]2·6H2O (1) (H4egta = ethyleneglycol-bis-(2aminoethylether)-N,N,N,N′-tetraacetic acid) and (mnH)4[EuIII2(dtpa)2]·6H2O (2) (H5dtpa = diethylenetriamine-N,N,N,N″,N″-pentaacetic acid), have been synthesized and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction. X-ray diffraction reveals that 1 is multinuclear nine-coordinate and crystallizes in the monoclinic crystal system with space group C2/c. The obtained cell dimensions are a = 38.513(3)?Å, b = 13.5877(8)?Å, c = 8.7051(5)?Å, β = 99.6780(10)°, and 4490.6(5)?Å3. Each methylamine (mnH+) cation in 1, through hydrogen bonds, connects three adjacent [EuIII(egta)]? anions. The [EuIII(egta)]? anions connect one another forming a 1-D multinuclear zigzag chain structure along the c-axis. Complex 2 is nine-coordinate binuclear structure with tricapped trigonal prismatic conformation and crystallizing in the monoclinic crystal system, but with space group P21/n. The obtained cell dimensions are a = 9.9132(8)?Å, b = 24.1027(18)?Å, c = 10.7120(10)?Å, β = 109.1220(10)°, and 2418.2(3)?Å3. For 2, there are two kinds of methylamine cations (mnH+) connecting [EuIII2(dtpa)2]4? complex anions and lattice waters through hydrogen bonds, leading to formation of a 2-D ladder-like layer structure.  相似文献   

11.
Two novel rare-earth metal complexes, namely, mononuclear Na4[EuIII(Dtpa)(H2O)]2 · 11.5H2O (I) and binuciear (NH4)4[EuIII(Dtpa)]2 · 10H2O (II) (H5Dtpa = diethylenetriamine-N,N,N??,N??,N??-pentaacetic acid), have successfully been synthesized and characterized by infrared spectrum, UV-Vis spectrum, fluorescence spectrum, thermal analysis, and single-crystal X-ray diffraction techniques. Since these two Eu(III) complexes have different counterions, causing different coordination environment, fluorescence spectrum analysis displays different fluorescence properties. X-ray diffraction reveals that the coordination polyhedra of both complexes adopt pseudo-D 3h tricapped trigonal prismatic conformation. However, I is a nine-coordinate mononuclear complex and crystallizes in the monoclinic crystal space group P21/n and II is a nine-coordinate binuciear complex and crystallizes in the triclinic crystal space group $P\bar 1$ . In addition, II has two independent binuciear structural units, [Eu(1)2(Dtpa)2] and [Eu(2)2(Dtpa)2]. Along the yz plane both [Eu(1)2(Dtpa)2] and [Eu(2)2(Dtpa)2] form a 1D chain structure, respectively. Further, along the y axis linking of each other forms a 2D planar structure.  相似文献   

12.
The three title complexes, NH4[HoIII(Edta)(H2O)3] · 1.5H2O (I) (H4Edta = ethylenedianine-N,N,N′,N′-tetraacetic acid), (NH4)4[Ho 2 III (Dtpa)2] · 9H2O (II) (H5Dtpa = diethylenetriamine-N,N,N′,N″,N″-entaacetic acid), and (NH4)3[HoIII(Ttha)] · 5H2O (III) (H6 Ttha = triethylenetetramine-N,N,N′,N″,N?,N?-hexaacetic acid), have been prepared and characterized by FT-IR, elemental analyses, and single-crystal X-ray diffraction technique. Complex I has a nine-coordinate mononuclear structure with distorted monocapped square antiprismatic conformation and its crystal structure belongs to orthorhombic system and Fdd2 space group. The crystal data are as follows: a = 19.343(9), b = 35.125(17), c = 12.364(6) Å, V = 8400(7) Å3, Z = 16, M = 552.26, ρcalcd = 1.747 g cm?3 μ = 3.828 mm?1, and F(000) = 4368. Complex II has a binuclear nine-coordinate pseudomonocapped square antiprismatic conformation and its crystal structure belongs to triclinic system and space P1 group. The crystal data are as follows: a = 9.7637(16), b = 9.9722(16), c = 12.945(2) Å, α= 85.853(2)°, β = 77. 140(2)°, γ = 77.140(2)°, V = 1198.4(3) Å3, Z = 1, M = 1340.80, ρcalcd = 1.858 g cm?3, μ = 3.380 mm?1, and F(000) = 674. As for complex III, it also has nine-coordinate mononuclear structure with distorted tricapped trigonal prism and its crystal structure belongs to monoclinic system andP21/c space group. The crystal data are as follows: a = 10.349(3), b = 12.760(4), c = 23.142(7) Å, β = 91.020(6)°, V = 3055.6(16) Å3, Z = 2, M = 797.55, ρcalcd = 1.734 g cm?3, μ = 2.674 mm?1, and F(000) = 1624. The results showed that although the ligands are different from one another in the shape and the numbers of coordination atoms, they all have nine-coordinate structures. However, one of them has binuclear structure and the other two have mononuclear structures because of the difference of the ligands.  相似文献   

13.
14.
Two title complexes, [TbIII(Eg3a)(H2O)2] · 4.5H2O (I) (H3Eg3a = 3-carboxymethyl-6, 9-dioxa-3,12-diazatetradecanedioic acid) and K[TbIII(Edta)(H2O)3] · 5H2O(II) (H4Edta = ethylenediamine-N,N,N′,N′-tetraaceti acid), were prepared and characterized by FT-IR, elemental analyses, TGA-DTA-DTG, and single-crystal X-ray diffraction technique. For I, the Tb3+ ion is nine-coordinated by an Eg3a ligand and two coordination water molecules, yielding a monocapped square-antiprismatic (MCSAP) conformation. Complex I crystallizes in the monoclinic system with P21/c space group. The crystal data are as follows: a = 9.237(3), b = 10.018(3), c = 23.580(7) Å, β = 99.021(5)°, V = 2155.2(11) Å3, Z = 4, ρ = 1.822 Mg m?3, μ = 3.353 mm?1, F(000) = 1180, R 1 = 0.0445 and wR 2 = 0.1034 for 4262 observed reflections with I ≥ 2σ(I). For II, the Tb3+ ion is nine-coordinated by an Edta ligand and three coordinate water molecules also yielding a MCSAP conformation. Complex II crystallizes in the orthorhombic system with Fdd2 space group. The crystal data are as follows: a = 19.373(5), b = 35.429(10), c = 12.114(3) Å, V = 8315(4) Å3, Z = 16, ρ = 2.014 Mg m?3, μ = 2.014 mm?1, F(000) = 5024, R 1 = 0.0224 and wR 2 = 0.0557 for 3189 observed reflections with I ≥ 2σ(I). The potassium cations bridge the coordination spheres yielding many infinite long 1-D zigzag-type chains. The molecular structure of I is more stable than that of II. According to thermal analyses, the collapsing temperatures of crystal structure are 314°C for I and 348°C for II, which indicates that the crystal structure of II is more stable.  相似文献   

15.
Compounds p-HOOCC6F4COOH · H2O (H2L · H2O), [Tb2(H2O)4(L)3 · 2H2O] n (I), and Tb2(Phen)2(L)3 · 2H2O (II) are synthesized. According to the X-ray structure analysis data, the crystal structure of H2L · H2O is built of centrosymmetric molecules H2L and molecules of water of crystallization. The crystal structure of compound I is built of layers of coordination 2D polymer [Tb2(H2O)4(L)3] n and molecules of water of crystallization. The ligands are the L2? anions performing both the tetradentate bridging and pentadentate bridging-chelating functions. The coordination polyhedron TbO9 is a distorted three-capped trigonal prism. Acid H2L manifests photoluminescence in the UV region (??max = 368 nm). Compounds I and II have the green luminescence characteristic of the Tb3+ ions, and the band with ??max = 545 nm (transition 5 D 4?? 7 F 5) is maximum in intensity. The photoluminescence intensity of compound II is higher than that for compound I.  相似文献   

16.
Complexes [Ca(H2O)2(Dmf@CB[6])(Bdc)] · DMF · 4H2O (I) and [Ca(H2O)3(Dmf@CB[6])]Cl2 · 2H2O (II) are synthesized by the heating (95°C) of a mixture of calcium chloride and cucurbit[6]uril (CB[6]) in a mixture of dimethylformamide (DMF) and water with the addition of terephthalic acid (H2Bdc) in the case of complex I or triethylamine for complex II. The compounds are characterized by X-ray diffraction analysis, IR spectroscopy, and thermogravimetric and elemental analyses. The luminescence spectra are also recorded. According to the X-ray diffraction data, the calcium atom is coordinated by the oxygen atoms of the cucurbit[6]uril molecule, water molecules, and terephthalate anion (for I). The internal cavity of the cavitand is occupied by DMF.  相似文献   

17.
18.
From hydrothermal treatment of benzene-1,2-diamine, pyrocatechol, and MoO3 in acetic acid solution, a new compound, [Mo22-O)2(C6H4O2)2(H2O)] · (C8H9N2)2 · 2H2O (I), constructed from pyrocatechol chelated dinuclear molybdenum units and 2-methylbenzimidazole has been synthesized. Single-crystal structure analysis reveals that the compound crystallizes in the monoclinic space group P21/c with a = 23.365(2), b = 7.2214(5), c = 19.3021(16) β = 97.929(4), V = 3225.6(5), Z = 4, M = 808.46, ρc = 1.665 g/cm3, μ(MoK α) = 0.84 mm?1, F(000) = 1608, the final R = 0.0622 and wR = 0.1484 for 7385 independent reflections with R int = 0.0393. Interestingly, an in situ condensation between acetic acid and benzene-1,2-diamine has occurred, and the unexpected 2-methyl-1-H-benzo[d] imidazoles serve as counterions and N-H donors to form stable hydrogen-bond network in the crystal. Furthermore, intermolecular hydrogen bonds are found among the cations, anions and crystalline water molecules. The double nuclear molybdenum units are connected by O-H...O hydrogen bonds with the crystalline water molecules to form one-dimensional chains, and the chains are further joined together by N-H...O to form a quasi-two dimensional structure.  相似文献   

19.
(enH2)5[(VO)12O6B18O36(OH)6]·2(H3O)·6H2O的水热合成和晶体结构   总被引:1,自引:0,他引:1  
以NH4VO3,H3BO3,乙二胺,MoO3,H2O为原料,按物质的量比2∶20∶9∶3∶222,在180℃条件下晶化,得到黑色棱形晶体(enH2)5[(VO)12O6B18O36(OH)6].2(H3O).6H2O.单晶结构分析结果表明该化合物属三斜晶系,Pī空间群,晶胞参数a=1.336 8(3)nm,b=1.599 8(3)nm,c=1.663 4(3)nm,α=94.040(1)°,β=91.530(1)°,γ=95.830(1)°,V=3.528 1(12)nm3,Z=2,Dc=2.099 g/cm3,μ=1.649 mm-1,F(000)=2 228,15 641个可观察独立衍射点射点(I>2σ(I)),最后结构精修到偏离因子R1=0.047 5,wR2=0.150 4,S=1.039.该化合物的结构主要由阴离子簇[(VO)12O6B18O36(OH)6]12-构成.该阴离子簇由B18O36(OH)6十八元环夹在两个以共边交替相连形成的V6O18簇中间,通过共用氧原子形成三明治式结构新颖的硼-钒-氧离子簇,簇间填充了一些(enH2)2+离子和水分子.  相似文献   

20.
The eight-coordinate (enH2)[YIII(pdta)(H2O)](2)·10H2O (en=ethylenediamine and H4pdta=1,3-propylenediamine-N,N,N',N'-tetraacetic acid) was synthesized, meanwhile its molecular and crystal structures were determined by single-crystal X-ray diffraction technology. The interaction between [Y(III)(pdta)(H2O)]2(2-) and bovine serum albumin (BSA) was investigated by UV-vis and fluorescence spectra. The results indicate that [YIII(pdta)(H2O)]2(2-) quenched effectively the intrinsic fluorescence of BSA via a static quenching process with the binding constant (Ka) of the order of 10(4). Meanwhile, the binding and damaging sites to BSA molecules were also estimated by synchronous fluorescence. Results indicate that the hydrophobic environments around Trp and Tyr residues were all slightly changed. The thermodynamic parameters (ΔG=-25.20 kJ mol(-1), ΔH=-26.57 kJ mol(-1) and ΔS=-4.58 J mol(-1) K(-1)) showed that the reaction was spontaneous and exothermic. What is more, both ΔH and ΔS were negative values indicated that hydrogen bond and Van der Waals forces were the predominant intermolecular forces between [YIII(pdta)(H2O)]2(2-) and BSA.  相似文献   

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