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1.
Pyridine Complexes of Rare Earth Element Trichlorides. Syntheses and Crystal Structures of [YCl3(py)4] and [LnCl3(py)4] · 0.5 py with Ln = La and Er The pyridine complexes [YCl3(py)4] ( 1 ), [LaCl3(py)4] · 0.5 py ( 2 · 0.5 py), and [ErCl3(py)4] · 0.5 py ( 3 · 0.5 py) have been prepared from the diacetone‐alcohol complexes [LnCl3(DAA)2] or directly from the metal trichlorides with excess pyridine to give colourless, only sparingly moisture sensitive crystals. They were characterized by IR spectroscopy and by crystal structure determinations. 1 : Space group Pbca, Z = 16, lattice dimensions at –80 °C: a = 1647.4(1), b = 1743.1(1), c = 3190.5(1) pm, R1 = 0.031. 2 · 0,5 Py: Space group P21/n, Z = 4, lattice dimensions at –80 °C: a = 978.9(1), b = 1704.5(1), c = 1589.5(1) pm, β = 103.61(1)°, R1 = 0.0281. 3 · 0,5 Py: Space group P21/n, Z = 4, lattice dimensions at –80 °C: a = 970.1(1), b = 1706.4(1), c = 1566.1(1) pm, β = 103.46(1)°, R1 = 0.0232. All complexes realize monomeric molecular structures with the metal atom in a distorted pentagonal‐bipyramidal coordination. One of the chlorine atoms and the four pyridine molecules are in the equatorial plane. 相似文献
2.
Pyridinium Chlorometallates of Lanthanoid Elements. Crystal Structures of [HPy]2[LnCl5(Py)] mit Ln = Eu, Er, Yb und von [H(Py)2][YbCl4(Py)2] · Py The pyridinium chlorometallates [HPy]2[LnCl5(Py)] with Ln = Eu, Er and Yb, as well as [H(Py)2][YbCl4(Py)2]·Py have been obtained by the reaction of diacetone alcohol with solutions of the corresponding metal trichlorides in pyridine at 100 °C. According to the crystal structure determinations the anions [LnCl5(Py)]2— are linked by bifurcated Cl···H···Cl bridges with the protons of the [HPy]+ cations forming chains along [001]. The anions of [H(Py)2][YbCl4(Py)2]·Py form discrete octahedrons with trans‐positions of the pyridine ligands. [HPy]2[EuCl5(Py)] ( 1a ): Space group Pnma, Z = 4, lattice dimensions at —80 °C: a = 1874.4(2), b = 1490.2(2), c = 741.5(1) pm, R1 = 0.0466. [HPy]2[ErCl5(Py)] ( 1b ): Space group Pnma, Z = 4, lattice dimensions at —80 °C: a = 1864.3(1), b = 1480.7(2), c = 739.7(1) pm, R1 = 0.0314. [HPy]2[YbCl5(Py)] ( 1c ): Space group Pnma, Z = 4, lattice dimensions at —80 °C: a = 1858.9(2), b = 1479.0(1), c = 736.8(1) pm, R1 = 0.0306. [H(Py)2][YbCl4(Py)2]·Py ( 2 ·Py): Space group Ia, Z = 4, lattice dimensions at —80 °C: a = 1865.5(1), b = 827.5(1), c = 1873.4(1) pm, ß = 103.97(1)°, R1 = 0.0258. 相似文献
3.
Benjamin J. Hellmann Ajay Venugopal Dr. Andreas Mix Dr. Beate Neumann Hans‐Georg Stammler Dr. Alexander Willner Dr. Tanja Pape Alexander Hepp Dr. Norbert W. Mitzel Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(43):11701-11709
The reaction of the donor‐functionalised N,N‐bis(2‐{pyrid‐2‐yl}ethyl)hydroxylamine and [LnCp3] (Cp=cyclopentadiene) resulted in the formation of bis(cyclopentadienyl) hydroxylaminato rare‐earth metal complexes of the general constitution [Ln(C5H5)2{ON(C2H4‐o‐Py)2}] (Py= pyridyl) with Ln=Lu ( 1 ), Y ( 2 ), Ho ( 3 ), Sm ( 4 ), Nd ( 5 ), Pr ( 6 ), La ( 7 ). These compounds were characterised by elemental analysis, mass spectrometry, NMR spectroscopy (for compounds 1 , 2 , 4 and 7 ) and single‐crystal X‐ray diffraction experiments. The complexes exhibit three different aggregation modes and binding motifs in the solid state. The late rare‐earth metal atoms (Lu, Y, Ho and Sm) form monomeric complexes of the formula [Ln(C5H5)2{η2‐ON(C2H4‐η1‐o‐Py)(C2H4‐o‐Py)}] ( 1 – 4 , respectively), in which one of the pyridyl nitrogen donor atoms is bonded to the metal atom in addition to the side‐on coordinating hydroxylaminato unit. The larger Nd3+ and Pr3+ ions in 5 and 6 make the hydroxylaminato unit capable of dimerising through the oxygen atoms. This leads to the dimeric complexes [(Ln(C5H5)2{μ‐η1:η2‐ON(C2H4‐o‐Py)2})2] without metal–pyridine bonds. Compound 7 exhibits a dimeric coordination mode similar to the complexes 5 and 6 , but, in addition, two pyridyl functions coordinate to the lanthanum atoms leading to the [(La(C5H5)2{ON(C2H4‐o‐Py)}{μ‐η1:η2‐ON(C2H4‐η1‐o‐Py)})2] complex. The aggregation trend is directly related to the size of the metal ions. The complexes with coordinative pyridine–metal bonds show highly dynamic behaviour in solution. The two pyridine nitrogen atoms rapidly change their coordination to the metal atom at ambient temperature. Variable‐temperature (VT) NMR experiments showed that this dynamic exchange can be frozen on the NMR timescale. 相似文献
4.
Philipp R. Matthes Jörn Nitsch Ana Kuzmanoski Prof. Claus Feldmann Dr. Andreas Steffen Prof. Todd B. Marder Prof. Klaus Müller‐Buschbaum 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(51):17369-17378
A series of 12 dinuclear complexes [Ln2Cl6(μ‐4,4′‐bipy)(py)6], Ln=Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, ( 1 – 12 , respectively) was synthesized by an anhydrous solvothermal reaction in pyridine. The complexes contain a 4,4′‐bipyridine bridge and exhibit a coordination sphere closely related to luminescent lanthanide MOFs based on LnCl3 and 4,4‐bipyridine. The dinuclear complexes therefore function as a molecular model system to provide a better understanding of the luminescence mechanisms in the Ln‐N‐MOFs ${\hbox{}{{\hfill 2\atop \hfill \infty }}}$ [Ln2Cl6(4,4′‐bipy)3] ? 2(4,4′‐bipy). Accordingly, the luminescence properties of the complexes with Ln=Y, Sm, Eu, Gd, Tb, Dy, ( 1 , 4 – 8 ) were determined, showing an antenna effect through a ligand–metal energy transfer. The highest efficiency of luminescence is observed for the terbium‐based compound 7 displaying a high quantum yield (QY of 86 %). Excitation with UV light reveals typical emission colors of lanthanide‐dependent intra 4f–4f‐transition emissions in the visible range (TbIII: green, EuIII: red, SmIII: salmon red, DyIII: yellow). For the GdIII‐ and YIII‐containing compounds 6 and 1 , blue emission based on triplet phosphorescence is observed. Furthermore, ligand‐to‐metal charge‐transfer (LMCT) states, based on the interaction of Cl? with EuIII, were observed for the EuIII compound 5 including energy‐transfer processes to the EuIII ion. Altogether, the model complexes give further insights into the luminescence of the related MOFs, for example, rationalization of Ln‐independent quantum yields in the related MOFs. 相似文献
5.
Yongfeng Yang Tao Li Yanmei Chen 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):903-907
The title compound, poly[[diaqua‐1κ2O‐tetrakis(μ3‐pyridine‐2,3‐dicarboxylato)‐2:1:2′κ10N,O2:O2′,O3:O3′;2:1:2′κ8O3:O3′:N,O2‐diiron(III)strontium(II)] dihydrate], {[Fe2Sr(C7H3O4)4(H2O)2]·2H2O}n, which has triclinic (P) symmetry, was prepared by the reaction of pyridine‐2,3‐dicarboxylic acid, SrCl2·6H2O and Fe(OAc)2(OH) (OAc is acetate) in the presence of imidazole in water at 363 K. In the crystal structure, the pyridine‐2,3‐dicarboxylate (pydc2−) ligand exhibits μ3‐η1,η1:η1:η1 and μ3‐η1,η1:η1,η1:η1 coordination modes, bridging two FeIII cations and one SrII cation. The SrII cation, which is located on an inversion centre, is eight‐coordinated by six O atoms of four pydc2− ligands and two water molecules. The coordination geometry of the SrII cation can be best described as distorted dodecahedral. The FeIII cation is six‐coordinated by O and N atoms of four pydc2− ligands in a slightly distorted octahedral geometry. Each FeIII cation bridges two neighbouring FeIII cations to form a one‐dimensional [Fe2(pydc)4]n chain. The chains are connected by SrII cations to form a three‐dimensional framework. The topology type of this framework is tfj . The structure displays O—H...O and C—H...O hydrogen bonding. 相似文献
6.
Masahiro Nagaoka Hiroyuki Tsuruda Dr. Masa‐aki Amako Prof. Dr. Hiroharu Suzuki Prof. Dr. Toshiro Takao 《Angewandte Chemie (International ed. in English)》2015,54(49):14871-14874
A μ3‐η2:η2:η2‐silane complex, [(Cp*Ru)3(μ3‐η2:η2:η2‐H3SitBu)(μ‐H)3] ( 2 a ; Cp*=η5‐C5Me5), was synthesized from the reaction of [{Cp*Ru(μ‐H)}3(μ3‐H)2] ( 1 ) with tBuSiH3. Complex 2 a is the first example of a silane ligand adopting a μ3‐η2:η2:η2 coordination mode. This unprecedented coordination mode was established by NMR and IR spectroscopy as well as X‐ray diffraction analysis and supported by a density functional study. Variable‐temperature NMR analysis implied that 2 a equilibrates with a tautomeric μ3‐silyl complex ( 3 a ). Although 3 a was not isolated, the corresponding μ3‐silyl complex, [(Cp*Ru)3(μ3‐η2:η2‐H2SiPh)(H)(μ‐H)3] ( 3 b ), was obtained from the reaction of 1 with PhSiH3. Treatment of 2 a with PhSiH3 resulted in a silane exchange reaction, leading to the formation of 3 b accompanied by the elimination of tBuSiH3. This result indicates that the μ3‐silane complex can be regarded as an “arrested” intermediate for the oxidative addition/reductive elimination of a primary silane to a trinuclear site. 相似文献
7.
Guo‐Ming Wang Hai‐Lan Huang Hui Li Qing‐Hua Zheng 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m531-m533
The two isomorphous lanthanide coordination polymers, {[Ln2(C6H4NO2)2(C8H4O4)(OH)2(H2O)]·H2O}n (Ln = Er and Tm), contain two crystallographically independent Ln ions which are both eight‐coordinated by O atoms, but with quite different coordination environments. In both crystal structures, adjacent Ln atoms are bridged by μ3‐OH groups and carboxylate groups of isonicotinate and benzene‐1,2‐dicarboxylate ligands, forming infinite chains in which the Er...Er and Tm...Tm distances are in the ranges 3.622 (3)–3.894 (4) and 3.599 (7)–3.873 (1) Å, respectively. Adjacent chains are further connected through hydrogen bonds and π–π interactions into a three‐dimensional supramolecular framework. 相似文献
8.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)2(η2‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character. 相似文献
9.
《无机化学与普通化学杂志》2018,644(6):346-352
A series of 3D d–f heterometallic coordination polymers, {[Ln2Zn(Pzdc)4(H2O)6] · 2H2O}n [Ln = La ( 1 ), Pr ( 2 ), Nd ( 3 ), Sm ( 4 ), Eu ( 5 ), Gd ( 6 ), Tb ( 7 ), Dy ( 8 )] (H2Pzdc = 2,3‐pyrazine dicarboxylic acid), were synthesized by one‐pot reactions under hydrothermal conditions. X‐ray crystallographical analysis and powder X‐ray diffraction analysis reveal that the complexes 1 – 8 are isostructural and adopt a multi‐parallel quadrilateral channel network structure with {4.6 · 2}2{4 · 2.6 · 2.8 · 2}{6 · 3}2{6 · 5.8}2 topology, in which the central LnIII ion is nine‐coordinate by four oxygen atoms and two nitrogen atoms from four ligands and three oxygen atoms from three coordinated H2O molecules and the central ZnII ion is six‐coordinate by four oxygen atoms and two nitrogen atoms from four ligands. Moreover, the photophysical properties related to the electronic transition for complexes 4 , 5 , 7 , and 8 were investigated by the excitation and emission spectra as well as the emission lifetimes. 相似文献
10.
Prof. Dr. Masahiro Sadakane Sachie Moroi Yoshifumi Iimuro Dr. Natalya Izarova Prof. Dr. Ulrich Kortz Prof. Dr. Shinjiro Hayakawa Kazuo Kato Dr. Shuhei Ogo Dr. Yusuke Ide Prof. Dr. Wataru Ueda Prof. Dr. Tsuneji Sano 《化学:亚洲杂志》2012,7(6):1331-1339
Ruthenium(III)‐substituted α‐Keggin‐type silicotungstates with pyridine‐based ligands, [SiW11O39RuIII(Py)]5?, (Py: pyridine ( 1 ), 4‐pyridine‐carboxylic acid ( 2 ), 4,4′‐bipyridine ( 3 ), 4‐pyridine‐acetamide ( 4 ), and 4‐pyridine‐methanol ( 5 )) were prepared by reacting [SiW11O39RuIII(H2O)]5? with the pyridine derivatives in water at 80 °C and then isolated as their hydrated cesium salts. These compounds were characterized using cyclic voltammetry (CV), UV/Vis, IR, and 1H NMR spectroscopy, elemental analysis, titration, and X‐ray absorption near‐edge structure (XANES) analysis (Ru K‐edge and L3‐edge). Single‐crystal X‐ray analysis of compounds 2 , 3 , and 4 revealed that RuIII was incorporated in the α‐Keggin framework and was coordinated by pyridine derivatives through a Ru? N bond. In the solid state, compounds 2 and 3 formed a dimer through π? π interaction of the pyridine moieties, whereas they existed as monomers in solution. CV indicated that the incorporated RuIII–Py was reversibly oxidized into the RuIV–Py derivative and reduced into the RuII–Py derivative. 相似文献
11.
Georgy K. Fukin Lev N. Zakharov Stanislav V. Maslennikov Alexander V. Piskunov Vladimir K. Cherkasov 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1020-1021
X‐ray diffraction shows that the title cadmium(II) complex, [Cd2(C14H20O2)2(C5H5N)6]·2C5H5N, has a dimeric structure in which two (py)3Cd(3,5‐di‐tert‐butylcatecholate) units (py is pyridine) are connected by two bridging O atoms, the coordination of the Cd atoms being distorted octahedral. There are two symmetrically independent dimers in the crystal structure; one is in a general position and the other lies about an inversion centre. In both cases, the bridging Cd—O distances between the Cd–catecholate units [2.224 (2)–2.237 (2) Å] are shorter than the bridging Cd—O distances within the catecholate cycle [2.273 (2)–2.281 (2) Å]. The Cd—Npy distances are 2.354 (2)–2.471 (2) Å. Besides the main molecules, the crystal also contains pyridine solvate molecules. 相似文献
12.
Andreas Fischer 《无机化学与普通化学杂志》2003,629(4):634-636
By slow evaporation of solutions containing Ln(ClO4)3 (Ln = Sm, Gd), H5IO6 and an excess of HClO4, crystals of the title compounds could be obtained. Their structures were determined by single‐crystal X‐ray diffraction. The compounds crystallize in the monoclinic crystal system, space group P21/c. They contain Ln3+ ions, which are coordinated by [H2I2O10]4— anions forming two‐dimensional, cationic networks. These are separated by perchlorate ions, forming a layered structure. 相似文献
13.
Binuclear dichlorido(η6‐p‐cymene)ruthenium(II) complexes with bis(nicotinate)‐ and bis(isonicotinate)‐polyethylene glycol ester ligands 下载免费PDF全文
Thomas Eichhorn Evamarie Hey‐Hawkins Danijela Maksimović‐Ivanić Marija Mojić Jürgen Schmidt Sanja Mijatović Harry Schmidt Goran N. Kaluđerović 《应用有机金属化学》2015,29(1):20-25
Neutral binuclear ruthenium complexes 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 of the general formula [{RuCl2(η6‐p‐cym)}2 μ‐(N∩N)] (N∩N = bis(nicotinate)‐ and bis(isonicotinate)‐polyethylene glycol esters: (3‐py)COO(CH2CH2O)nCO(3‐py) and (4‐py)COO(CH2CH2O)nCO(4‐py), n =1–4), as well as mononuclear [RuCl2(η6‐p‐cym)((3‐py)COO(CH2CH2OCH3)‐κN)], complex 9 , were synthesized and characterized using elemental analysis and electrospray ionization high‐resolution mass spectrometry, infrared, 1H NMR and 13C NMR spectroscopies. Stability of the binuclear complexes in the presence of dimethylsulfoxide was studied. Furthermore, formation of a cationic complex containing bridging pyridine‐based bidentate ligand was monitored using 1H NMR spectroscopy. Ligand precursors, polyethylene glycol esters of nicotinic ( L1 · 2HCl– L4 · 2HCl and L9 · HCl) and isonicotinic acid dihydrochlorides ( L5 · 2HCl– L8 · 2HCl), binuclear ruthenium(II) complexes 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 and mononuclear complex 9 were tested for in vitro cytotoxicity against 518A2 (melanoma), 8505C (anaplastic thyroid cancer), A253 (head and neck tumour), MCF‐7 (breast tumour) and SW480 (colon carcinoma) cell lines. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
14.
Recrystallization of Ln(NO3)3 (Ln = Sm, Eu, Yb) in the presence of 18‐crown‐6 under aqueous conditions yielded [Ln(NO3)3(H2O)3] · 18‐crown‐6. X‐ray crystallography revealed isomorphous structures for each of the lanthanide complexes where [Ln(NO3)3(H2O)3] is involved in hydrogen bonding interactions with 18‐crown‐6. The transition point where the structural motif changes from [Ln(18‐crown‐6)(NO3)3] (with the metal residing in the crown cavity) to [Ln(NO3)3(H2O)3] · 18‐crown‐6 has been identified as at the Nd/Sm interface. A similar investigation involving [Ln(tos)3(H2O)6] (tos = p‐toluenesulfonate) and 18‐crown‐6 were resistant to crown incorporation. X‐ray studies show extensive intra‐ and intermolecular hydrogen bonding is present. 相似文献
15.
Reaction of divalent Sm(OAr)2(THF)3 (Ar = C6H2‐tert‐Bu3‐2,4,6; THF = tetrahydrofuran) with one equivalent of azobenzene in THF and crystallization of the product in diethyl ether afforded the title complex (ArO)2(THF)2Sm(η2‐N2Ph2)·Et2O in good yield. In the complex, the N? N bond length for the azobenzene species is lengthened. The two Sm? N bonds are equivalent, and their bond lengths are intermediate between the donor bond and the single bond. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
16.
Ana María Atria María Angeles Mora María Teresa Garland Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m490-m493
The polymeric title compounds, namely catena‐poly[[[di‐μ‐but‐2‐enoato‐κ3O:O,O′;κ3O,O′:O′‐bis[diaquadibut‐2‐enoato‐κO;κ2O,O′‐neodymium(III)]]‐μ‐4,4′‐bipyridyl N,N′‐dioxide‐κ2O:O′] 4,4′‐bipyridyl N,N′‐dioxide solvate] and the erbium(III) and yttrium(III) analogues, {[Ln2(C4H5O2)6(C10H8N2O2)(H2O)4]·C10H8N2O2}n (Ln = Nd, Er and Y), form from [Ln2(bt)6(H2O)4] dimers (bt is but‐2‐enoate) bridged by 4,4′‐bipyridyl dioxide (bno) spacers into sets of parallel chains; these linear arrays are interconnected by aqua‐mediated hydrogen bonds into broad two‐dimensional structures, which in turn interact with each other though the hydrogen‐bonded bridged bno solvent units. Both independent bno units in the structures are bisected by symmetry centres. 相似文献
17.
Karel Mach Jií Kubita Ivana Císaov Petr tpni
ka 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):m116-m118
Reacting stoichiometric amounts of 1‐(diphenylphosphino)ferrocenecarboxylic acid and [Ti(η5‐C5HMe4)2(η2‐Me3SiC[triple‐bond]CSiMe3)] produced the title carboxylatotitanocene complex, [{μ‐1κ2O,O′:2(η5)‐C5H4CO2}{2(η5)‐C5H4P(C6H5)2}{1(η5)‐C5H(CH3)4}2FeIITiIII] or [FeTi(C9H13)2(C6H4O2)(C17H14P)]. The angle subtended by the Ti/O/O′ plane, where O and O′ are the donor atoms of the κ2‐carboxylate group, and the plane of the carboxyl‐substituted ferrocene cyclopentadienyl is 24.93 (6)°. 相似文献
18.
Two Oxime‐Based {LnIII3NiII3} Clusters with Triangular {Ln3(μ3‐Ο2)}7+ Core: Solvothermal Syntheses,Crystal Structures,and Magnetic Properties 下载免费PDF全文
Xiao‐Ting Wang Hui‐Ming Dong Xiu‐Guang Wang En‐Cui Yang Xiao‐Jun Zhao 《无机化学与普通化学杂志》2016,642(20):1166-1172
Two isostructural heterometallic complexes, {[Dy3Ni3(H2O)3(mpko)9(O2)(NO3)3](ClO4) · 3CH3OH · 3CH3CN} ( 1 ) and {[Gd3Ni3(H2O)3(mpko)9(O2)(NO3)3](NO3) · 10.75CH3OH} ( 2 ) [mpkoH = 1‐(pyrazin‐2‐yl)ethanone oxime], were solvothermally synthesized by varying lanthanide ions with different magnetic anisotropy. Structural analyses revealed that both complexes contain a peroxide anion‐aggregated triangular {Ln3(μ3‐Ο2)}7+ core, which is surrounded by three NiII octahedra through threefold oxime linkages into a heterometallic hexanuclear cluster. Apparent antiferromagnetic interactions are observed between the adjacent spin carriers of 1 and 2 with the coupling constant JLn ··· Ni ≈ 12JLn ··· Ln. Additionally, 1 with highly anisotropic DyIII site shows slow magnetization relaxation under zero dc field and 2 constructed from isotropic GdIII ion displays significant cryogenic magnetocaloric effect with a maximum entropy change of 24.8 J · kg–1 · K–1 at 3.0 K and 70 kOe. 相似文献
19.
Ling‐Zhi Zhao Yuan‐Yuan Tian Ying‐Xin Gong Xiao‐Ting Huang Fen Zhang Jian‐Xiong Rong Xia Cai Wen‐Tao Li Rong‐Hua Zeng Dong‐Sheng Lu 《无机化学与普通化学杂志》2014,640(1):147-152
Two 2D 4d‐4f heterometallic coordination polymers, [LnAg(Py26DC)2(H2O)3] · 3H2O [Ln = Nd ( 1 ), La ( 2 ); H2Py26DC = pyridine‐2,6‐dicarboxylic acid], and one 2D lanthanide homometallic coordination polymer, [Ln(Py25DC)(ox)0.5(H2O)2] [Ln = Tm ( 3 ); H2Py25DC = pyridine‐2,5‐dicarboxylic acid; ox = oxalate], were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Both complexes 1 and 2 are isostructural and exhibit 3‐connected 2D heterometallic layer structures with the Schläfli symbol of (82 · 10), whereas complex 3 represents an extended 2D homometallic network structure with (4,4) topology. 相似文献
20.
Tong‐Hen Pan Kun‐Shan Huang Chong‐En Huang Fu‐Long Lai Chang‐Cang Huang 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(2):m46-m49
The asymmetric unit of the title coordination polymer, [Gd2(C7H4O5S)2(C2O4)(H2O)6]n or [Gd(2‐SB)(ox)0.5(H2O)3]2n (2‐SB is 2‐sulfonatobenzoate and ox is oxalate), (I), consists of one GdIII ion, one 2‐SB anion, three coordinated water molecules and one half of an ox ligand. The ox ligand is located on a crystallographic inversion centre. The GdIII centre shows a distorted tricapped trigonal–prismatic coordination formed by nine O atoms from two 2‐SB anions, one ox ligand and three coordinated water molecules. The carboxylate and sulfonate groups of the 2‐SB anions adopt μ2‐η1:η2 and μ1‐η0:η0:η1 coordination modes to link two GdIII ions, generating a centrosymmetric binuclear [Gd2(2‐SB)2(H2O)6]2− subunit. The ox ligand acts as a bridge, linking the binuclear [Gd2(2‐SB)2(H2O)6]2− subunits into a one‐dimensional chain structure parallel to the b axis. Furthermore, extensive O—H...O hydrogen bonds connect the chains into a three‐dimensional supramolecular architecture. 相似文献