共查询到20条相似文献,搜索用时 15 毫秒
1.
Min Liu 《Inorganica chimica acta》2009,362(8):2884-513
Two novel metal-organic frameworks [Zn3(BTC)2(bbi)3]n (1) (H3BTC = 1,3,5-benzenetricarboxylate, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) and{[Zn3(BTC)2(bix)3 · 2.5H2O]}n (2) (bix = 1,4-bis(imidazole-1-ylmethyl)benzene) have been hydrothermally prepared and characterized. Analysis of the structure of 1 displays a 3D framework exhibiting a threefold interpenetration net of identical Zn1.5(BTC)(bbi)1.5 single frameworks. In the structure of 2, BTC3− and bix build up infinite tubes extending to a 3D non-interpenetrated porous framework. Moderate fluorescent emissions in the solid state at room temperature were observed in both the compounds. 相似文献
2.
Salah S. Massoud Franz A. Mautner Febee R. Louka Sebastian Dechert 《Inorganica chimica acta》2011,370(1):435-443
The reaction of aqueous solutions of the preformed 1:1 Cu(ClO4)2-polydentate amine with tetrasodium 1,2,4,5-benzene tetracarboxylate (Na4bta) afforded three different types of polynuclear compounds. These include the tetranuclear complexes: [Cu4(Medpt)4(μ4-bta)(ClO4)2(H2O)2](ClO4)2·2H2O (1), [Cu4(pmdien)4(μ4-bta)(H2O)4](ClO4)4 (2), [Cu4(Mepea)4(μ4-bta)(H2O)2](ClO4)4(3), [Cu4(TPA)4(μ4-bta)](ClO4)4·10H2O (4) and [Cu4(tepa)4(μ4-bta)](ClO4)4·2H2O (5), the di-nuclear: [Cu2(DPA)2(μ2-bta)(H2O)2]·4H2O (6), [Cu2(dppa)2(μ2-bta)(H2O)2]·4H2O (7) and [Cu2(pmea)2(μ2-bta)]·14H2O (8) and the trinuclear complex [Cu3(dppa)3(μ3-bta)(H2O)2.25](ClO4)2·6.5H2O (9) where Medpt = 3,3′-diamino-N-methyldipropylamine, pmedien = N,N,N′,N″,N″-pentamethyldiethylenetriamine, Mepea = [2-(2-pyridyl)ethyl]-(2-pyridylmethyl)methylamine, TPA = tris(2-pyridylmethyl)amine, tepa = tris[2-(2-pyridyl)ethyl)]amine, DPA = di(2-pyridymethyl)amine, dppa = N-propanamide-bis(2-pyridylmethyl)amine and pmea = bis(2-pyridylmethyl)-[2-(2-pyridylethyl)]amine. The complexes were structurally characterized by elemental analyses, spectroscopic techniques, and by X-ray crystallography for complexes 1, 2, 4, 6, 7 and 9. X-ray structure of the complexes reveal that bta4− is acting as a bridging ligand via its four deprotonated caboxylate groups in 1, 2 and 4, three carboxylate groups in 9 and via two trans-carboxylates in 6 and 7. The complexes exhibit extended supramolecular networks with different dimensionality: 1-D in 2 and 4 due to hydrogen bonds of the type O-H···O, 2-D in 1 and 7, and 3-D network in 6 as a result of hydrogen bonds of the types N-H···O and O-H···O. Magnetic susceptibility measurements showed very weak antiferromagnetic coupling between the CuII ions in 1-5, 7-9 (|J| = 0.02-0.87 cm−1) and weak ferromagnetic coupling for 6 (J = 0.08 cm−1). 相似文献
3.
Christopher L. Sheppard Santokh S. Tandon Laurence K. Thompson John N. Bridson David O. Miller Makoto Handa Francesc Lloret 《Inorganica chimica acta》1996,250(1-2):227-239
Two novel, weakly antiferromagnetically coupled, tetranuclear copper(II) complexes [Cu4(PAP)2(μ2-1,1-N3)2(μ2-1,3-N3)2(μ2-CH3OH)2(N3)4 (1) (PAP = 1,4-bis-(2′-pyridylamino)phthalazine) and [Cu4(PAP3Me)2 (μ2-1,1-N3)2(μ2-1,3-N3)2(H2O)2(NO2)2]- (NO3)2 (2) (PAP3Me = 1,4-bis-(3′-methyl-2′-pyridyl)aminophthalazine) contain a unique structural with two μ2-1,1-azide intramolecular bridges, and two μ2-1,3-azide intermolecular bridges linking pairs of copper(II) centers. Four terminal azide groups complete the five-coordinate structures in 1, while two terminal waters and two nitrates complete the coordination spheres in 2. The dinuclear complexes [Cu2(PPD)(μ2-1,1-N3)(N3)2(CF3SO3)]CH3OH) (3) and [Cu2(PPD)(μ2-1,1-N3)(N3)2(H2O)(ClO4)] (4) (PPD = 3,6-bis-(1′-pyrazolyl)pyridazine) contain pairs of copper centers with intramolecular μ2-1,1-azid and pyridazine bridges, and exhibit strong antiferromagnetic coupling. A one-dimensional chain structure in 3 occurs through intermolecular μ2-1,1-azide bridging interactions. Intramolecular Cu-N3-Cu bridge angles in 1 and 2 are small (107.9 and 109.4°, respectively), but very large in 3 and 4 (122.5 and 123.2°, respectively), in keeping with the magnetic properties. 2 crystallizes in the monoclinic system, space group C2/c with a = 26.71(1), b = 13.51(3), c = 16.84(1) Å, β = 117.35(3)° and R = 0.070, Rw = 0.050. 3 crystallizes in the monoclinic system, space group P21/c with a = 8.42(1), b = 20.808(9), c = 12.615(4) Å, β = 102.95(5)° and R = 0.045, Rw = 0.039. 4crystallizes in the triclinic system, space group P1, with a = 10.253(3), b = 12.338(5), c = 8.072(4) Å, = 100.65(4), β = 101.93(3), γ = 87.82(3)° and R = 0.038, Rw = 0.036 . The magnetic properties of 1 and 2 indicate the presence of weak net antiferromagnetic exchange, as indicated by the presence of a low temperature maximum in χm (80 K (1), 65 K (2)), but the data do not fit the Bleaney-Bowers equation unless the exchange integral is treated as a temperature dependent term. A similar situation has been observed for other related compounds, and various approaches to the problem will be discussed. Magnetically 3 and 4 are well described by the Bleaney-Bowers equation, exhibiting very strong antiferromagnetic exchange (− 2J = 768(24) cm−1 (3); − 2J = 829(11) cm−1 (4)). 相似文献
4.
Two new complexes [Cu(NITmPy)2(tp)] 1 and [Ni(NITmPy)2(tp)(H2O)2] 2 (NITmPy=2-(3′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and tp=terephthalato dianion) were synthesized and structurally and magnetically characterized. The structure of 1 is a neutral infinite chain where Cu(NITmPy)2 units are linked by terephthalate ligands. In complex 2, the 1-D chains of Ni(NITmPy)2 (H2O)2 units connected by tp develop into 2-D network via hydrogen bond interactions. The magnetic properties of 1 and 2 have been investigated in the temperature range 2-300 K. Both complexes exhibit ferromagnetic coupling and antiferromagnetic interactions dominate at low temperature. The magnetic behavior is discussed based on their structures. 相似文献
5.
Annamaria Camus Alessandro Facchinetti Nazario Marsich Anna Maria Manotti Lanfredi Franco Ugozzoli 《Inorganica chimica acta》1999,290(2):2043-188
The formation of complexes between copper(II) halides and 2,2′-dipyridylamine (dipyam) has been studied systematically. Only complexes with a 1:1 and 1:2 metal-to-ligand ratio are formed. Some mixed chloro–iodide and halide–PF6 compounds have also been isolated. The X-ray diffraction structures of the [Cu(dipyam)2Br2] · 2H2O (I) and the [Cu(dipyam)2Cl]2I2 · 2CH3CN (II) complexes are reported. I is a rare example of an octahedral coordination among the copper(II) halide complexes of dipyam. The two bromo atoms, which occupy the apical positions, are H-bonded to the water molecules of crystallization. II is a dimer, where each copper forms a cationic chloro-complex of approximately trigonal bipyramidal geometry, the dimerization being due to hydrogen bonds formed by the NH group of one of the two dipyams coordinated to each metal atom with the chlorine atom of the centrosymmetric cationic complex. The iodide anions are hydrogen-bonded to the NH groups of the dipyams not involved in the dimerization. 相似文献
6.
Ganna A. Senchyk Eduard B. Rusanov Harald Krautscheid 《Inorganica chimica acta》2009,362(12):4439-4448
A series of coordination compounds [Cd2(trad)7Br2][Cd(trad)Br3]2 (1), [Cd3(trad)6{N(CN)2}4(H2O)2](N(CN)2)2 (2), [{Cd2(trad)5}{Cd(N(CN)2)6}]·3CH3OH (3), [{Cd3(trad)6(SeCN)2}{Cd(SeCN)4}2] (4), [Cd2(trad)3(NCS)4] (5), [Cd3(tr2ad)3(μ-NCS)3](NCS)3 (6), [Cd3(tr2ad)6](NO3)6·22H2O (7), [Cu3(tr2ad)4(SO4)(H2O)3](SO4)2·34H2O (8) and [Cu2(OH)(tr2ad)2](NO3)3·4H2O (9) (trad = 4-(adamantan-1-yl)-1,2,4-triazole; tr2ad = 1,3-bis(1,2,4-triazol-4-yl)-adamantane) revealed the potential of 1,2,4-triazolyl functionalized adamantanes for design of metal-organic polymers incorporating polynuclear coordination units as multiconnected nodes. Structures 1-5 are based upon characteristic di- and trinuclear clusters involving triple triazole bridges [M(μ2-trad)3M] (M = Cd), while doubling of the ligand functionality (tr2ad) allows integration of the clusters into 3D polymeric frameworks 6-9 (M = Cd, Cu). 相似文献
7.
Michal EshelAvi Bino 《Inorganica chimica acta》2002,329(1):45-50
Heating an aqueous solution of the trinuclear ‘basic’ chromium(III) acetate led to the formation of several products which were separated by ion-exchange chromatography. Crystals of a new cyclic, hexanuclear Cr(III) compound, [Cr6(OH)10(O2CCH3)6(H2O)4]Cl2·13H2O (3·Cl2·13H2O) were obtained upon elution of the violet complex 3 with 0.5 M NaCl and slow evaporation of the eluent. The six chromium atoms in complex 3 form an almost planar, irregular hexagon with an overall symmetry close to C2h. By heating solid ‘basic’ chromium(III) acetate at 300 °C, followed by ion-exchange separation, a new hexanuclear complex, [Cr6O3(OH)(O2CCH3)9(H2O)4]2+ (4) has been obtained. Complex 4 has a {Cr6O4} core, which consists of a {Cr4O4} cubane type inner core with two external chromium centers attached to μ4-oxo(cube) ligands. A similar procedure, using ‘basic’ chromium(III) propionate led to the isolation of the dodecanuclear complex [Cr12O8(O2CCH2CH3)16(H2O)8]4+ (5) which has a {Cr12O8} core. The {Cr6O4} core in complex 4 can be regarded to be formed from a tetranuclear {Cr4O2} butterfly unit and a dinuclear {Cr2O2} unit. Similarly, the {Cr12O8} core in 5 can be considered to be constructed from two orthogonal {Cr6O4} units as in complex 4. 相似文献
8.
Ademir Neves Cludio N. Verani Marcos A. de Brito Ivo Vencato Antnio Mangrich Glaucius Oliva Dulce D.H.F. Souza Alzir A. Batista 《Inorganica chimica acta》1999,290(2):2221-212
Copper(II) complexes were synthesized and characterized by means of elemental analysis, IR and visible spectroscopies, EPR and electrochemistry, as well as X-ray structure crystallography. The group consists of discrete mononuclear units with the general formula [Cu(II)(Hbpa)2](A)2·nH2O, where Hbpa=(2-hydroxybenzyl-2-pyridylmethyl)amine and A=ClO4 −, n=2 (1), CH3COO−, n=3 (2), NO3 −, n=2 (3) and SO4 2−, n=3 (4). The structures of the ligand Hbpa and complex 1 have been determined by X-ray crystallography. Complexes 1–4 have had their UV–Vis spectra measured in both MeCN and DMF. It was observed that the compounds interact with basic solvents, such that molecules coordinate to the metal in axial positions in which phenol oxygen atoms are coordinated in the protonated forms. The values were all less than 1000 M−1 cm−1. EPR measurements on powdered samples of 1–3 gave g/A values between 105 and 135 cm−1, typical for square planar coordination environments. Complex 4·3H2O exhibits a behaviour typical for tetrahedral coordination. The electrochemical behaviour for complexes 1 and 2 was studied showing irreversible redox waves for both compounds. 相似文献
9.
Gerard A. van Albada Wilberth J.J. Smeets Anthony L. Spek Jan Reedijk 《Inorganica chimica acta》1997,260(2):164-161
Based on the new ligand bis(1-methyl-2-benzimidazolyl) propane (abbreviated as mtbz) several new copper(II) coordination compounds have been prepared and characterized structurally and spectroscopically. Two representative compounds, i.e. [Cu2(mtbz)2(CH3)2- (CF3SO3)](CF3SO3) (1) and [Cu2(mtbz)2(CH3O)2](ClO4)2 (4) were characterized structurally by X-ray diffraction. Crystal data for 1: monoclinic, space group P21/c, a=13.6585(5), B=39.981(3), C=20.919(1) Å, β=125.98(1)°, Z=8. Crystal data for 4: monoclinic, space group P21/c, a=13.115(2), B=9.523(2), C=17.908(4) Å, β=111.71(1)°, Z=2. Structures 1 and 4 each consist of a dinuclear unit with bridging methoxo groups and one ligand linked to each copper via an N atom. Structure 1 (which consists of two dinuclear, crystallographically independent, but chemically identical units) has the two copper atoms bridged by a triflate anion, providing each copper atom a square-pyramidal coordination, while the copper atoms in structure 4 have an almost a square-planar geometry. The Cu---Cu distances (Å) within the dinuclear units are: 1, 2.9775(13), 2.9751(13); 4, 2.9872(16); the Cu---O---Cu bridging angles (°) are: 1, 101.7(3), 101.7(3), 100.9(3), 102.1(3); 4, 103.2(2). The mid-IR section focused on the vibrations of the triflate anion reveals interesting results concerning the assignments of that anion related to the vas(S---O) band. Characteristic Cu---O vibrations in the far-IR section were found at 386 and 230 cm−1 for the methoxo-bridged and 454 and 332 cm−1 for the ethoxo-bridged compounds. These dinuclear species are EPR silent, and only a weak signal of monomeric impurities is observed. They also show a diamagnetic behavior below room temperature. 相似文献
10.
Salah S. Massoud Febee R. Louka Masahiro Mikuriya Franz A. Mautner 《Inorganica chimica acta》2011,366(1):394-398
In aqueous solution, the reaction of Cu(ClO4)2 and di(2-pyridylmethyl)amine, DPA with the disodium salt of pyrazole-3,5-dicarboxylate (Na2Hpzdc) in presence of sodium azide afforded the azido complex [Cu3(DPA)3(μ-pzdc)(μ-N3)](ClO4)2·2H2O (1) whereas when reaction was conducted in absence of sodium azide the perchlorato complex [Cu3(DPA)3(μ-pzdc)(μ-ClO4)](ClO4)2·3H2O (2) was obtained. The complexes were structurally characterized by physicochemical techniques and by single crystal X-ray crystallography in case of 1. The coordination sphere of the two complexes which are iso-structural polymeric 1D systems consist of three independent Cu(DPA) units, one pzdc bridging ligand and one end-on bridging azido group in 1 or one bridging perchlorato group in 2. The three Cu(II) centers in both complexes may be described as axially elongated octahedral. Magnetic susceptibility measurements reveal the weak anti-ferromagnetic coupling in the two complexes (J = −23.2 cm−1 for 1 and −14.8 cm−1 for 2). 相似文献
11.
Arindam Mukherjee Indranil Rudra Munirathinam Nethaji 《Inorganica chimica acta》2004,357(4):1077-1082
Alkoxo-phenoxo bridged tetranuclear copper(II) complexes [Cu4L2(O2CC6H4-p-OH)2] (1) and [Cu4L2(O2CC6H4-o-OH)2] (2) containing pentadentate Schiff base ligand N,N′-(2-hydroxypropane-1,3-diyl)bis(salicylaldimine) (H3L) are prepared and structurally characterized. Crystal structures of the complexes show the covalent linkage between two {Cu2L(O2CR)}(R = C6H4-p-OH, C6H4-o-OH) units through the phenoxo atoms of the Schiff base ligand showing axial/equatorial bonding modes. The Cu(1)-O(2)-Cu(2) alkoxo bridge angle is 131° in 1 and 2. The pendant ortho- and para- OH groups of the three-atom bridging carboxylate ligands show no apparent bonding interactions with the metal or other group(s). The complexes show a d-d band near 635 nm in CH2Cl2. Variable temperature magnetic susceptibility measurements in the temperature range 300-18 K show antiferromagnetically coupled spin system. A theoretical fit of the magnetic data using exchange parameters J1 and J2 for the intradimer and interdimer units of the quasi-linear tetrameric core gave values as: J1=−132,J2=−72 cm−1 for 1 and J1=−167,J2=−67 cm−1 for 2. 相似文献
12.
Patrick GamezRosienne H Steensma Willem L Driessen Jan Reedijk 《Inorganica chimica acta》2002,333(1):51-56
The tridentate ligand 2,6-bis(pyrazol-3-yl)pyridine (dPzPy) renders coordination compounds with halide, nitrate and tetrafluoroborate salts of copper. The complexes, which have the form [Cu(dPzPy)X2] with X=Br and Cl, [Cu(dPzPy)(NO3)2](H2O), and [Cu(dPzPy)2](BF4)(SiF6)0.5(MeOH)3 have been characterized by elemental analysis and by IR, EPR and ligand field spectroscopy. The single-crystal X-ray structure of [Cu(C11H9N5)Br2] shows the copper(II) ion to be coordinated by three N atoms of 2,6-bis(pyrazol-3-yl)pyridine and two bromides in a geometry exactly in between a trigonal-bipyramid and a square-pyramid. Each molecule lies on a crystallographic C2-symmetry axis. They are coupled to one another by a two-dimensional network through NH to Br hydrogen bonds. The crystal structure of [Cu(C11H9N5)Cl2] is analogous to the bromide. The single-crystal X-ray structure of [Cu(dPzPy)2](BF4)(SiF6)0.5(MeOH)3 shows the copper ion to be in a Jahn-Teller distorted octahedral N6 environment of two mer-oriented tridentate ligands. 相似文献
13.
14.
Xiao-Qing Shen Hai-Bin Qiao Hong-Yun Zhang Hong-Lei Liu Pei-Kun Chen 《Inorganica chimica acta》2006,359(2):642-648
A new heterometallacrown coordination polymer [K2Cu(NPA)2(H2O)4]n (where H2NPA = 3-nitro-phthalic acid) has been synthesized and it’s crystal structure has been elucidated. In the complex, the o-phthalate group coordinates to metal atoms behaving as both tetradentate and heptadentate coordination, the modes of which have been found for the first time. The thermal behaviors of this complex and the thermal decomposition kinetics have been studied. Kinetic analysis shows that the decomposition of title complex in the main range acts as two separate transitions with the first one being a double-step following reaction, , and the second being a three-step following reaction of t:f,f, . The kinetic parameters of these processes were also obtained. 相似文献
15.
Gerard A van AlbadaIlpo Mutikainen Wilberth J.J SmeetsAnthony L Spek Urho TurpeinenJan Reedijk 《Inorganica chimica acta》2002,327(1):134-139
The synthesis, optical and magnetic properties and X-ray crystal structure of [Cu(2-aminopyrimidine)2(OH)(CF3SO3)]2(2-aminopyrimidine)2, a new dinuclear hydroxo-bridged copper(II) compound with a CuOCu angle of 97.96° and a very small antiferromagnetic interaction for which the singlet-triplet exchange parameter J, is described. The magnetic exchange coupling is almost negligible and, depending on the actual sample, varies from −1.8 to −7.2 cm−1. 相似文献
16.
Christiane Fernandes Ademir Neves Adailton J. Bortoluzzi Antnio S. Mangrich Eva Rentschler Bruno Szpoganicz Erineu Schwingel 《Inorganica chimica acta》2001,320(1-2):12-21
The crystal structure, magnetic, redox and spectroscopic properties of a novel unsymmetrical dinuclear copper(II) complex, prepared by the reaction between copper(II) perchlorate, sodium acetate and the unsymmetrical, binucleating ligand HTPPNOL, where HTPPNOL is N,N,N′-tris-(2-pyridylmethyl)-1,3-diaminopropan-2-ol, is reported. HTPPNOL (1 equiv.) reacted with 1 equiv. of copper(II) ion, in methanol, and produced the mononuclear copper complex [Cu(TPPNOL)](ClO4)(BPh4) (1). On the other hand, the reaction of 1 equiv. of HTPPNOL with 2 equiv. each of copper (II) ion and acetate, in methanol, produced the dinuclear complex [Cu2(TPPNOL)(OOCCH3)](ClO4)2 (2), whose structure has been determined by X-ray diffraction. In complex 2, as a result of the inherent asymmetry of the ligand HTPPNOL, one copper ion is five-coordinated (distorted trigonal-bipyramidal) while the other copper is four-coordinated (distorted square-planar). Then, as a result of the presence of distinct geometries for the metal centres, complex 2 exhibits a ferromagnetic coupling (J=+25.41 cm−1). Titration experiments carried out on the dinuclear complex suggest a pKa=8.0, which was related to the aquo/hydroxo equilibrium. Complex 2 is able to oxidise 3,5-di-tert-butylcatechol to the respective o-quinone. The oxidation reaction was studied by following the appearance of the quinone spectrophotometrically, at pH 8.0 and 25 °C. 相似文献
17.
The X-ray structure is reported for the complex Cu2(medpco-2H)Cl2, (medpco = N,N′-bis-N,N-dimethylaminoethyl)pyridine-2,6-dicarboxamide 1-oxide. The complex is triclinic,
, a=8.313(4), B=11.403(5), C=11.611(3) Å, =91.66(3), β=108.99(4), γ=109.60(3)° and Z=2. The deprotonated ligand (medpco-2H)2− acts as a binulceating ligand, producing an N-oxide-bridged complex. Each copper in Cu2(medpco-2H)Cl2 is five-coordinate, being coordinated by a bridging N-oxide oxygen, a deprotonated amide nitrogen, a tertiary amine nitrogen and two bridging chlorides. The complex does not exhibit significant magnetic interaction, and this may be the result of distortion of the bridging geometry from planarity. A range of other, apparently N-oxide-bridged, complexes of the type Cu2(medpco-2H)X2 is reported. The complex Cu2(medpco-2H)Br2·H2O is strongly antiferromagnetic, with magnetic data closely fitting the expected binuclear structure. 相似文献
18.
Michiko B. Inoue Motomichi Inoue Lorena Machi Francisco Brown Quintos Fernando 《Inorganica chimica acta》1995,230(1-2):145-151
Reactions between 1,1′-dibenzyl-4,4′-bipyridinium(2+) (benzylviologen, BzV) chloride and cyanocuprates(I) gave two charge-transfer complexes having different colors: dark brown (BzV)3Cu9(CN)15·H2O and light brown (BzV)Cu(CN)3·2H2O. An X-ray crystal analysis of the former compound showed that nine crystallographically nonequivalent Cu atoms form three kinds of triad ---Cu---(CN)---Cu--- screws, which are linked by CN groups resulting in a unique three-dimensional network structure. Three of the nine Cu atoms have distorted tetrahedral (td) coordination geometries while the others have triangular plane (tp) geometries. Each screw consists of a (-tp-td-tp-)n array. There are three crystallographically nonequivalent viologen molecules. Certain CuCN moieties are located above a viologen ring or by the side of a viologen ring, with close interatomic contacts. These close contacts are characteristic of the charge-transfer complex and are responsible for the deep color of the complex. 相似文献
19.
X-ray crystal analyses of divalent copper, cobalt and calcium complexes of monoanionic (3-hydroxy-5-(hydroxymethyl)-2-methylisonicotinic acid) 5-phosphate (L1C8H9NO7P−) revealed the chemical compositions of Cu
---L·3H2O(1), Co
---L·5H2O(2) and Ca·L2·7H2O (3) and the coordination structures which depend on the coordination abilities and chemical properties of the respective metal ions. Although 1 and 2 crystals showed similar features, i.e., presence of the metal ion at the crystallographic center of symmetry and octahedral six-coordination, the patterns of coordination with the ligand molecules differed. While direct coordination to the L carboxyl oxygen was observed in 1 crystals, all ligation positions in 2 crystals were occupied by water molecules. On the other hand, 3 crystals formed a pentagonal bipyramidal structure (seven-coordination), where oxygens of L phosphates and water molecules coordinated to the calcium ion. Each of the complex structures showed characteristic molecular packing depending on the pattern of coordination to the respective metal ion. L is monoanionic in all complex crystals, where the phosphate and carboxyl groups are deprotonated and pyridine nitrogen is protonated, and is neutralized by each metal ion. Crystal data: 1, monoclinic, space group P21/c, A = 5.4129(6), B = 10.515(2), C = 22.770(2) Å, β = 91.853(9)°, Z = 4, R = 0.0404 for 1834 observed reflections; 2, triclinic, space group
, c = 6.789(3) Å, α = 96.84(3), β = 109.10(3), γ = 100.50(2)°, Z = 2, R = 0.0684 for 1605 observed reflections; 3, triclinic,
, a = 10.069(2), B = 14.501(3), c = 10.051(1) Å, α = 100.75(1), β = 97.28(2), γ = 76.18(2)°, Z = 2, R = 0.0540 for 3637 observed reflections. 相似文献
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20.
Complex pbt2Cu8Br12 [pbt=pyridine-2,6-diylbis(methyleneamino-TEMPO)] was synthesized from CuBr2 and a new ligand pbt, and characterized by means of X-ray crystal structure analysis and magnetic measurements. The centrosymmetric molecule consists of a Cu6Br10 cluster sandwiched with two pbt·CuBr complexes. Detailed geometrical analysis and magnetic analysis reveal the presence of four copper(I) and four copper(II) ions in a molecule. Antiferromagnetic couplings observed can be attributed to the intermolecular radical?radical and intramolecular copper(II)?copper(II) interactions. 相似文献