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1.
The title compound, [Nd(C7H3O6S)(H2O)]n or [Nd(SSA)(H2O)]n (H3SSA is 5‐sulfosalicylic acid), was synthesized by the hydrothermal reaction of Nd2O3 with H3SSA in water. The compound forms a three‐dimensional network in which the asymmetric unit contains one NdIII atom, one SSA ligand and one coordinated water mol­ecule. The central NdIII ion is eight‐coordinate, bonded to seven O atoms from five different SSA ligands [Nd—O = 2.405 (4)–2.612 (4) Å] and one aqua O atom [Nd—OW = 2.441 (4) Å].  相似文献   

2.
Ruthenium(II) Complexes containing pyrimidine‐2‐thiolate (pymS) and bis(diphenylphosphanyl)alkanes [Ph2P–(CH2)m–PPh2, m = 1, dppm; m = 2, dppe; m = 3, dppp; m = 4, dppb] are described. Reactions of [RuCl2L2] (L = dppm, dppp) and [Ru2Cl4L3] (L = dppb) with pyrimidine‐2‐thione (pymSH) in 1:2 molar ratio in dry benzene in the presence of Et3N base yielded the [Ru(pymS)2L] complexes (pymS = pyrimidine‐2‐thiolate; L = dppm ( 1 ); dppp ( 3 ); dppb ( 4 )). The complex [Ru(pymS)2(dppe)] ( 2 ) was indirectly prepared by the reaction of [Ru(pymS)2(PPh3)2] with dppe. These complexes were characterized using analytical data, IR, 1H, 13C, 31P NMR spectroscopy, and X‐ray crystallography (complex 3 ). The crystal structure of the analogous complex [Ru(pyS)2(dppm)] ( 5 ) with the ligand pyridine‐2‐thiolate (pyS) was also described. X‐ray crystallographic investigation of complex 3 has shown two four‐membered chelate rings (N, S donors) and one six‐membered ring (P, P donors) around the metal atom. Compound 5 provides the first example in which RuII has three four‐membered chelate rings: two made up by N, S donor ligands and one made up by P, P donor ligand. The arrangement around the metal atoms in each complex is distorted octahedral with cis:cis:trans:P, P:N, N:S, S dispositions of the donor atoms. The 31P NMR spectroscopic data revealed that the complexes are static in solution, except 2 , which showed the presence of more than one species.  相似文献   

3.
Reaction of 1, 9‐dihydro‐purine‐6‐thione (puSH2) in presence of aqueous sodium hydroxide with PdCl2(PPh3)2 suspended in ethanol formed [Pd(κ2‐N7,S‐puS)(PPh3)2] ( 1 ). Similarly, complexes [Pd(κ2‐N7,S‐puS)(κ2‐P, P‐L‐L)] ( 2 – 4 ) {L‐L = dppm (m = 1) ( 2 ), dppp (m = 3) ( 3 ), dppb (m = 4) ( 4 )} were prepared using precursors the [PdCl2(L‐L)] {L‐L = Ph2P–(CH2)m–PPh2}. Reaction of puSH2 suspended in benzene with platinic acid, H2PtCl6, in ethanol in the presence of triethylamine followed by the addition of PPh3 yielded the complex [Pt(κ2‐N7,S‐puS)(PPh3)2] ( 5 ). Complexes [Pt(κ2‐N7,S‐puS)(κ2‐P, P‐L‐L)] ( 6 – 8 ) {L‐L = dppm ( 6 ), dppp ( 7 ), dppb ( 8 )} were prepared similarly. The 1, 9‐dihydro‐purine‐6‐thione acts as N7,S‐chelating dianion in compounds 1 – 8 . The reaction of copper(I) chloride [or copper(I) bromide] in acetonitrile with puSH2 and the addition of PPh3 in methanol yielded the same product, [Cu(κ2‐N7,S‐puSH)(PPh3)2] ( 9 ), in which the halogen atoms are removed by uninegative N, S‐chelating puSH anion. However, copper(I) iodide did not lose iodide and formed the tetrahedral complex, [CuI(κ1‐S‐puSH2)(PPh3)2] ( 10 ), in which the thio ligand is neutral. These complexes were characterized with the help of elemental analysis, NMR spectroscopy (1H, 31P), and single‐crystal X‐ray crystallography ( 3 , 7 , 8 , 9 , and 10 ).  相似文献   

4.
The title complex, catena‐poly[[[(2,2′‐bipyridine‐1κ2N,N′)tris(methanol‐2κO)(nitrato‐2κ2O,O′)‐μ‐cyanido‐1:2C:N‐cyanido‐1κC‐iron(II)neodymium(III)]‐di‐μ‐cyanido‐1:2′C:N;2:1′N:C] methanol solvate], {[FeIINdIII(CN)4(NO3)(C10H8N2)(CH3OH)3]·CH3OH}n, is made up of ladder‐like one‐dimensional chains oriented along the c axis. Each ladder consists of two strands based on alternating FeII and NdIII centers connected by cyanide bridges. Furthermore, two such parallel chains are connected by additional cyanide cross‐pieces (the `rungs' of the ladder), which likewise connect FeII and NdIII centers, such that each [Fe(CN)4(bipy)]2− unit (bipy is 2,2′‐bipyridine) coordinates with three NdIII centers and each NdIII center connects with three different [Fe(CN)4(bipy)]2− units. In the complex, the iron(II) cation is six‐coordinated with a distorted octahedral geometry and the neodymium(III) cation is eight‐coordinated with a distorted dodecahedral environment.  相似文献   

5.
Nd3NCl6 and Nd4NS3Cl3: Two Derivatives of Neodymium Nitride with Discrete Units of Edge‐Shared ([N2Nd6]12+) and Isolated [NNd4]9+ Tetrahedra, respectively For the preparation of Nd3NCl6 (orthorhombic, Pbca; a = 1049.71(8), b = 1106.83(8), c = 1621.1(1) pm; Z = 8) and Nd4NS3Cl3 (hexagonal, P63mc; a = 922.78(6), c = 683.06(4) pm; Z = 2) elemental neodymium is reacted with sodium azide (NaN3), neodymium trichloride (NdCl3) and in the case of Nd4NS3Cl3 additionally with sulfur in evacuated silica tubes at 750 °C (Nd3NCl6) and 850 °C (Nd4NS3Cl3), respectively. Thereby the hydrolysis‐sensitive nitride chloride forms coarse, brick‐shaped single crystals, while those of the insensitive nitride sulfide chloride emerge hexagonally and pillar‐shaped. The pale violet compounds each exhibit [NNd4] tetrahedra as characteristic structural features, which are connected via a common edge to form discrete pairs of tetrahedra ([N2Nd6]12+) in Nd3NCl6 and are present in Nd4NS3Cl3 even as isolated [NNd4]9+ units. Their three‐dimensional cross‐linkage as well as the charge‐balance regulation proceed solely through Cl anions in the nitride chloride, but through equimolar amounts of S2– and Cl anions in the nitride sulfide chloride. The crystal structure of Nd3NCl6 shows three crystallographically independent Nd3+ cations, each of which is eightfold coordinated by anions (Nd1: 2 N3– + 6 Cl; Nd2 and Nd3: 1 N3– + 7 Cl). Only two different kinds of Nd3+ underlie the structure of Nd4NS3Cl3: Nd1 is surrounded by one N3–, six S2– and three Cl with CN = 10, whereas one N3–, four S2– and three Cl only are coordinating Nd2 with CN = 8.  相似文献   

6.
Luminescent CuI complexes have emerged as promising substitutes for phosphorescent emitters based on Ir, Pt and Os due to their abundance and low cost. The title heteroleptic cuprous complex, [9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)‐9H‐xanthene‐κ2P ,P ](2‐methylquinolin‐8‐ol‐κ2N ,O )copper(I) hexafluorophosphate, [Cu(C10H9NO)(C39H32OP2)]PF6, conventionally abbreviated as [Cu(Xantphos)(8‐HOXQ)]PF6, where Xantphos is the chelating diphosphine ligand 9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)‐9H‐xanthene and 8‐HOXQ is the N ,O‐chelating ligand 2‐methylquinolin‐8‐ol that remains protonated at the hydroxy O atom, is described. In this complex, the asymmetric unit consists of a hexafluorophosphate anion and a whole mononuclear cation, where the CuI atom is coordinated by two P atoms from the Xantphos ligand and by the N and O atoms from the 8‐HOXQ ligand, giving rise to a tetrahedral CuP2NO coordination geometry. The electronic absorption and photoluminescence properties of this complex have been studied on as‐synthesized samples, whose purity had been determined by powder X‐ray diffraction. In the detailed TD–DFT (time‐dependent density functional theory) studies, the yellow emission appears to be derived from the inter‐ligand charge transfer and metal‐to‐ligand charge transfer (M +L ′)→LCT excited state (LCT is ligand charge transfer).  相似文献   

7.
The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT) with 4‐methylbenzaldehyde and 4‐methoxybenzaldehyde in ethanol led to the iminic derivatives ‐4‐(4‐methylbenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)thione ( L1 ) and 4‐(4‐methoxybenzyl‐ideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione ( L2 ). The reaction of L1 with CuCl in the presence of triphenylphosphane as co‐ligand in methanol/chloroform solution gave the CuI complex containing L1 , [Cu( L1 )(PPh3)2Cl]·0.5CH3OH·0.25CHCl3 ( 1 ). Treatment of L2 with the same metal salt in a molar ratio of 1:1 in methanol and further addition of a solution of PPh3 in chloroform led to the complex [Cu( L2 )(PPh3)2Cl]·2.5CHCl3 ( 2 ). The complexes and L1 were characterized by IR and NMR spectroscopy as well as by X‐ray diffraction studies. In both complexes, the Schiff base ligand is coordinated to the copper ion through its sulfur atom. The other coordination sites around the copper ion are occupied by two triphenylphosphane molecules and one chloride ion. Therefore, each CuI ion is in a distorted tetrahedral environment. Crystal data for L1 at ?100 °C: space group P21/n with a = 720.5(1), b = 1140.6(1), c = 1426.3(2) pm, β = 91.25(1)°, Z = 4, R1 = 0.03, for 1 at ?120 °C : space group with a = 1286.3(1), b = 1740.3(1), c = 2060.2(1) pm, α = 79.085(6), β = 83.827(5), γ = 76.688(6)°, Z = 4, R1 = 0.0649 and for 2 at ?80 °C : space group with a = 1183.7(2), b = 1370.1(2), c = 1812.1(3) pm, α = 85.69(2), β = 88.52(2), γ = 64.89(2)°, Z = 2, R1 = 0.0488.  相似文献   

8.
Lanthanide triflates have been used to incorporate NdIII and SmIII ions into the 2.2.2‐cryptand ligand (crypt) to explore their reductive chemistry. The Ln(OTf)3 complexes (Ln=Nd, Sm; OTf=SO3CF3) react with crypt in THF to form the THF‐soluble complexes [LnIII(crypt)(OTf)2][OTf] with two triflates bound to the metal encapsulated in the crypt. Reduction of these LnIII‐in‐crypt complexes using KC8 in THF forms the neutral LnII‐in‐crypt triflate complexes [LnII(crypt)(OTf)2]. DFT calculations on [NdII(crypt)]2+], the first NdII cryptand complex, assign a 4f4 electron configuration to this ion.  相似文献   

9.
The NdIII coordination compounds [Nd(4‐pytza)3(H2O)2] · 2H2O ( 1 ) and [Nd(4‐pytza)2(H2O)4]Cl · 2H2O ( 2 ) [H4‐pytza = 5‐(4‐pyridyl)tetrazole‐2‐acetic acid] were synthesized by reactions of K4‐pytza and NdCl3 · 6H2O at different pH values. Single crystal X‐ray diffraction analysis reveals that 4‐pytza ligands in 1 in a μ1,3‐COO synsyn or μ1,1,3‐COO bridging mode coordinate to two central NdIII atoms to display a dinuclear unit, which is connected by one of these 4‐pytza ligands acting in end‐to‐end bridging mode to form a 1D ladder‐like chain. Different from 1 , each 4‐pytza in 2 with a μ1,3‐COO synanti bridging mode coordinates to two NdIII atoms to display a 1D zigzag chain. Furthermore, the luminescence properties of 1 and 2 were investigated at room temperature in the solid state.  相似文献   

10.
A family of neodymium complexes featuring a redox‐active ligand in three different oxidation states has been synthesized, including the iminoquinone (L0) derivative, (dippiq)2NdI3 ( 1‐iq ), the iminosemiquinone (L1−) compound, (dippisq)2NdI(THF) ( 1‐isq ), and the amidophenolate (L2−) [K(THF)2][(dippap)2Nd(THF)2] ( 1‐ap ) and [K(18‐crown‐6)][(dippap)2Nd(THF)2] ( 1‐ap crown ) species. Full spectroscopic and structural characterization of each derivative established the +3 neodymium oxidation state with redox chemistry occurring at the ligand rather than the neodymium center. Oxidation with elemental chalcogens showed the reversible nature of the ligand‐mediated reduction process, forming the iminosemiquinone metallocycles, [K(18‐crown‐6)][(dippisq)2Nd(S5)] ( 2‐isq crown ) and [K(18‐crown‐6)(THF)][(dippisq)2Nd(Se5)] ( 3‐isq crown ), which are characterized to contain a 6‐membered twist‐boat ring.  相似文献   

11.
A series of free ligands, H2 L 1 , H2 L 2 , H2 L 3 , and H2 L 4 , designed for the coordination and sensitization of near‐infrared(NIR)‐emitting Nd3+ were synthesized by modifying the salophen Schiff base with different numbers and locations of Br‐substituents. The nature of the Nd3+ complexes in solution was determined to be [ML2]? by spectrophotometric titrations as an indication that the different substituents do not affect significantly the nature of the formed species. The structures were determined in the solid phase from X‐ray diffraction experiments. The stoichiometries and structures in the solid state are different from those observed in solution. We established that the structures in the solid state can be partially controlled by the crystallization conditions. The ligands L 1 – L 4 have the ability to sensitize Nd3+ through intramolecular energy transfer from the ligand to the metal ion. We quantified that the numbers and locations of Br‐substituents control the emitted luminescence intensity of the complex by the heavy‐atom effect.  相似文献   

12.
The rare‐earth metal germanides RE2Ge9 (RE = Nd, Sm) have been prepared by thermal decomposition of the metastable high‐pressure phases REGe5 at ambient pressure. The compounds adopt an orthorhombic unit cell with a = 396.34(4) pm; b = 954.05(8) pm and c = 1238.4(1) pm for Nd2Ge9 and a = 395.46(7) pm; b = 946.4(2) pm and c = 1232.1(3) pm for Sm2Ge9. Crystal structure refinements reveal space group Pmmn (No. 59) for Nd2Ge9. The atomic pattern resembles an ordered defect variety of the pentagermanide motif REGe5 (RE = La; Nd, Sm, Gd, Tb) comprising corrugated germanium layers. These condense into a three‐dimensional network interconnected by eight‐coordinated germanium atoms. The resulting framework channels along [100] enclose the neodymium atoms. With respect to the atomic arrangement of the pentagermanides, half of the interlayer germanium atoms are eliminated in an ordered way so that occupied and empty germanium columns alternate along [001]. The rare‐earth metal atoms of both types of compounds, REGe5 and RE2Ge9, exhibit the electronic states 4f 3 and 4f 5 (oxidation state +3) for neodymium and samarium, respectively, evidencing that the modification of the germanium network leaves the electron configuration of the metal atoms unaffected.  相似文献   

13.
The crystal structures of rare‐earth diaryl‐ or dialkylphosphate derivatives are poorly explored. Crystals of bis[bis(2,6‐diisopropylphenyl)phosphato‐κO ]chloridotetrakis(methanol‐κO )neodymium methanol disolvate, [Nd(C24H34O4P)Cl(CH4O)4]·2CH3OH, (1), and of the lutetium, [Lu(C24H34O4P)Cl(CH4O)4]·2CH3OH, (2), and yttrium, [Y(C24H34O4P)Cl(CH4O)4]·2CH3OH, (3), analogues have been obtained by reactions between lithium bis(2,6‐diisopropylphenyl)phosphate and LnCl3(H2O)6 (in a 2:1 ratio) in methanol. Compounds (1)–(3) crystallize in the C 2/c space group. Their crystal structures are isomorphous. The molecule possesses C 2 symmetry with a twofold crystallographic axis passing through the Ln and Cl atoms. The bis(2,6‐diisopropylphenyl)phosphate ligands all display a κ1O‐monodentate coordination mode. The coordination polyhedron for the metal atom [coordination number (CN) = 7] is a distorted pentagonal bipyramid. Each [Ln{O2P(O‐2,6‐iPr2C6H3)2}2Cl(CH3OH)4] molecular unit exhibits two intramolecular O—H…O hydrogen bonds, forming six‐membered rings, and two intramolecular O—H…Cl interactions, forming four‐membered rings. Intermolecular O—H…O hydrogen bonds connect each unit via four noncoordinating methanol molecules with four other units, forming a two‐dimensional hydrogen‐bond network. Crystals of bis[bis(2,6‐diisopropylphenyl)phosphato‐κO ]tetrakis(methanol‐κO )(nitrato‐κ2O ,O ′)neodymium methanol disolvate, [Nd(C24H34O4P)(NO3)(CH4O)4]·2CH3OH, (4), have been obtained in an analogous manner from NdCl3(H2O)6. Compound (4) also crystalizes in the C 2/c space group. Its crystal structure is similar to those of (1)–(3). The κ2O ,O ′‐bidentate nitrate anion is disordered over a twofold axis, being located nearly on it. Half of the molecule is crystallographically unique (CNNd = 8). Unlike (1)–(3), complex (4) exhibits disorder of all three methanol molecules, one isopropyl group of the phosphate ligand and the NO3 ligand. The structure of (4) displays intra‐ and intermolecular O—H…O hydrogen bonds similar to those in (1)–(3). Compounds (1)–(4) represent the first reported mononuclear bis[bis(diaryl/dialkyl)phosphate] rare‐earth complexes.  相似文献   

14.
A series of seven new tetrazole‐based ligands (L1, L3–L8) containing terpyridine or bipyridine chromophores suited to the formation of luminescent complexes of lanthanides have been synthesized. All ligands were prepared from the respective carbonitriles by thermal cycloaddition of sodium azide. The crystal structures of the homoleptic terpyridine–tetrazolate complexes [Ln(Li)2]NHEt3 (Ln=Nd, Eu, Tb for i=1, 2; Ln=Eu for i=3, 4) and of the monoaquo bypyridine–tetrazolate complex [Eu(H2O)(L7)2]NHEt3 were determined. The tetradentate bipyridine–tetrazolate ligand forms nonhelical complexes that can contain a water molecule coordinated to the metal. Conversely, the pentadentate terpyridine–tetrazolate ligands wrap around the metal, thereby preventing solvent coordination and forming chiral double‐helical complexes similarly to the analogue terpyridine–carboxylate. Proton NMR spectroscopy studies show that the solid‐state structures of these complexes are retained in solution and indicate the kinetic stability of the hydrophobic complexes of terpyridine–tetrazolates. UV spectroscopy results suggest that terpyridine–tetrazolate complexes have a similar stability to their carboxylate analogues, which is sufficient for their isolation in aerobic conditions. The replacement of the carboxylate group with tetrazolate extends the absorption window of the corresponding terpyridine‐ (≈20 nm) and bipyridine‐based (25 nm) complexes towards the visible region (up to 440 nm). Moreover, the substitution of the terpyridine–tetrazolate system with different groups in the ligand series L3–L6 has a very important effect on both absorption spectra and luminescence efficiency of their lanthanide complexes. The tetrazole‐based ligands L1 and L3–L8 sensitize efficiently the luminescent emission of lanthanide ions in the visible and near‐IR regions with quantum yields ranging from 5 to 53 % for EuIII complexes, 6 to 35 % for TbIII complexes, and 0.1 to 0.3 % for NdIII complexes, which is among the highest reported for a neodymium complex. The luminescence efficiency could be related to the energy of the ligand triplet states, which are strongly correlated to the ligand structures.  相似文献   

15.
Copper(I) halides with triphenyl phosphine and imidaozlidine‐2‐thiones (L ‐NMe, L ‐NEt, and L ‐NPh) in acetonitrile/methanol (or dichloromethane) yielded copper(I) mixed‐ligand complexes: mononuclear, namely, [CuCl(κ1‐S‐L ‐NMe)(PPh3)2] ( 1 ), [CuBr(κ1‐S‐L ‐NMe)(PPh3)2] ( 2 ), [CuBr(κ1‐S‐L ‐NEt)(PPh3)2] ( 5 ), [CuI(κ1‐S‐L ‐NEt)(PPh3)2] ( 6 ), [CuCl(κ1‐S‐L ‐NPh)(PPh3)2] ( 7 ), and [CuBr(κ1‐S‐L ‐NPh)(PPh3)2] ( 8 ), and dinuclear, [Cu21‐I)2(μ‐S‐L ‐NMe)2(PPh3)2] ( 3 ) and [Cu2(μ‐Cl)21‐S‐L ‐NEt)2(PPh3)2] ( 4 ). All complexes were characterized with analytical data, IR and NMR spectroscopy, and X‐ray crystallography. Complexes 2 – 4 , 7 , and 8 each formed crystals in the triclinic system with P$\bar{1}$ space group, whereas complexes 1 , 5 , and 6 crystallized in the monoclinic crystal system with space groups P21/c, C2/c, and P21/n, respectively. Complex 2 has shown two independent molecules, [(CuBr(κ1‐S‐L ‐NMe)(PPh3)2] and [CuBr(PPh3)2] in the unit cell. For X = Cl, the thio‐ligand bonded to metal as terminal in complex 4 , whereas for X = I it is sulfur‐bridged in complex 3 .  相似文献   

16.
Pale violet, needle‐shaped single crystals of the new neodymium(III) oxide chloride oxoselenate(IV) Nd7O5Cl3[SeO3]4 were obtained by the reaction of Nd2O3 and NdCl3 with SeO2 (molar ratio: 3:1:4) in evacuated silica ampoules within seven days at 775 °C, if an excess of CsCl worked as fluxing agent. Nd7O5Cl3[SeO3]4 crystallizes in the triclinic space group P with the lattice parameters a = 694.46(4), b = 944.53(5), c = 1567.92(9) pm, α = 87.821(3), β = 81.849(3), γ = 84.852(3)° and Z = 2. Its structure exhibits seven crystallographically different Nd3+ cations, of which (Nd1)3+ – (Nd4)3+ are coordinated by O2– anions forming distorted square prisms. The polyhedra of (Nd1)3+ and (Nd2)3+ receive additional caps by one Cl anion each, and (Nd5)3+ – (Nd7)3+ show mixed square antiprismatic environments of O2– and Cl anions too. However, the polyhedra of (Nd5)3+ and (Nd6)3+ include two, the polyhedron about (Nd7)3+ even three Cl anions. Two‐dimensional layers of edge‐ and vertex‐linked [ONd4]10+ tetrahedra are built up by (O1)2– – (O5)2– together with all Nd3+ cations. All the other oxygen atoms belong to four crystallographically different Se4+ cations erecting ψ1‐tetrahedral oxoselenate(IV) units [SeO3]2– with stereochemically active non‐bonding electron pairs (“lone pairs”) pointing into the free space between the layers. Three independent Cl anions in threefold coordination of Nd3+ cations interconnect the layers to form a three‐dimensional network, thereby achieving the charge balance.  相似文献   

17.
The title compound, [Nd2(C5H6O4)2(C8H4O4)(H2O)4]·17H2O, obtained via hydrothermal reaction of Nd2O3 with glutaric acid and terephthalic acid, assembles as a three‐dimensional open framework with ten‐coordinate Nd–O polyhedra. The asymmetric part of the unit cell contains half a glutarate anion, a quarter of a terephthalate dianion, half an NdIII cation, one coordinated water molecule and 4.25 solvent water molecules. Each [NdO10] coordination polyhedron is comprised of six O atoms originating from four glutarate anions, two others from a terephthalate carboxylate group, which coordinates in a bidentate fashion, and two from water molecules. The Nd—O distances range from 2.4184 (18) to 2.7463 (18) Å. The coordination polyhedra are interconnected by the glutarate anions, extending as a two‐dimensional layer throughout the bc plane. Individual two‐dimensional layers are interlinked via terephthalate anions along the a axis. This arrangement results in rectangular‐shaped cavities with interstices of approximately 3.5 × 6 × 6.5 Å (approximately 140 Å3), which are occupied by water molecules. The NdIII cations, terephthalate anions, glutarate anions and one of the interstitial water molecules are located on special crystallographic positions. The Nd–terephthalate–Nd units are located across twofold rotation axes parallel to [100], with the NdIII cations located directly on these axes. In addition, the terephthalate anion is bisected by a crystallographic mirror plane perpendicular to that axis, thus creating an inversion centre in the middle of the aromatic ring. The glutarate ligand is bisected by a crystallographic mirror plane perpendicular to (001). One of the solvent water molecules lies on a site of 2/m symmetry, and the symmetry‐imposed disorder of its H atoms extends to the H atoms of the other four solvent water molecules, which are disordered over two equally occupied and mutually exclusive sets of positions.  相似文献   

18.
The reaction of 4‐amino‐1, 2, 4‐triazin‐3(2H)‐thione‐5‐one (ATTO, 1 ) with [Cu(PPh3)2]NO3 in ethanol led to the complex [Cu(PPh3)2(ATTO)]NO3 ( 2 ). 2 was characterized by elemental analyses, IR, 1H NMR and Raman spectroscopy. A single‐crystal X‐ray diffraction of compound 2 revealed that ATTO acts as a bidentate ligand via its nitrogen and sulfur atoms. Crystal data for 2 at 20 °C: space group P21/n with a = 975.7(1), b = 1533.5(2), c = 2504.2(3) pm, β = 92.25(1)°, Z = 4, R1 = 0.0632.  相似文献   

19.
Two heterobimetallic Zn‐Nd phenylene‐bridged Schiff‐base ligands complexes [ZnNd L1 (Py)(NO3)3] ( 1 ) and [Zn L2 Nd(Py)(NO3)3]·MeCN ( 2 ) (Py = pyridine, H2L1 = N,N′‐bis‐ (3‐methoxy‐salicylidene)phenylene‐1,2‐diamine, H2L2 = N,N′‐bis‐5‐bromo‐3‐methoxy‐salicylidene)phenylene‐1,2‐diamine) were obtained. Both 1 and 2 were structurally characterized by X‐ray crystallography, and their near‐infrared (NIR) luminescent properties were determined. For the two complexes, the occupation of pyridine at the axial position of 3d Zn2+ ions could effectively prevent luminescent quenching arising from OH‐, NH‐ or CH oscillators of the solvates around the 4f Nd3+ ions, and the heavy‐atom (Br) effect of the Schiff‐base ligands on their NIR luminescent properties is also discussed.  相似文献   

20.
The rational synthesis of the 2‐{1‐methylpyridine‐N‐oxide‐4,5‐[4,5‐bis(propylthio)tetrathiafulvalenyl]‐1H‐benzimidazol‐2‐yl}pyridine ligand ( L ) is described. It led to the tetranuclear complex [Dy4(tta)12( L )2] ( Dy‐Dy2‐Dy ) after coordination reaction with the precursor Dy(tta)3?2 H2O (tta?=2‐thenoyltrifluoroacetonate). The X‐ray structure of Dy‐Dy2‐Dy can be described as two terminal mononuclear units bridged by a central antiferromagnetically coupled dinuclear complex. The terminal N2O6 and central O8 environments are described as distorted square antiprisms. The ac magnetism measurements revealed a strong out‐of‐phase signal of the magnetic susceptibility with two distinct sets of data. The high‐ and low‐frequency components were attributed to the two terminal mononuclear single‐molecule magnets (SMMs) and the central dinuclear SMM, respectively. A magnetic hysteresis loop was detected at very low temperature. From both structural and magnetic points of view, the tetranuclear SMM Dy‐Dy2‐Dy is a self‐assembly of two known mononuclear SMMs bridged by a known dinuclear SMM.  相似文献   

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