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1.
A new molecule-based weak ferromagnet of formula Fe[C6H5PO3].H2O was synthesized. It was characterized by thermogravimetric analysis and UV-visible and infrared spectroscopy, and the magnetic properties were studied using a superconducting quantum interference device magnetometer. The crystal structure of the compound was determined "ab initio" from X-ray powder diffraction data and refined by the Rietveld method. The crystals of Fe[C6H5PO3].H2O are orthorhombic, space group Pmn2(1), with a = 5.668(8) A, b = 14.453(2) A, c = 4.893(7) A, and Z = 2. The title compound is isostructural with the previously reported lamellar M[C6H5PO3].H2O, M = Mn(II), Zn(II), and Cd(II). The inorganic layers are made of Fe(II) ions octahedrally coordinated by five phosphonate oxygen atoms and one from oxygen of the water molecule. These layers are then separated by bilayers of the phenyl groups, and van der Waals contacts are established between them. The refinement has shown that the phenyl rings are disordered in the lattice. The oxidation state of the metal ion is +2, and the electronic configuration is d6 (S = 2) high-spin, as determined from dc magnetic susceptibility measurements from 150 K to room temperature. Below 100 K, the magnetic moment of Fe[C6H5PO3].H2O rises rapidly to a maximum at TN = 21.5 K, and then it decreases again. The peak at TN is associated with the 3D antiferromagnetic long-range ordering. Below the critical temperature, the title compound behaves as a "weak" ferromagnet, which represents the third type of magnetic materials characterized by having a finite zero-field magnetization, ferromagnets and ferrimagnets being the other two types. The large coercive field (i.e., 6400 G) observed in the hysteresis loop at T = 10 K is rare in molecule-based materials; it can be ascribed to a pronounced spin-orbit coupling for the 5T2g ground state of the Fe(II) ion in the octahedral environment.  相似文献   

2.
The tris(imido)methylrhenium complex CH3Re(NAd)3 (1a, Ad = 1-adamantyl) reacts with H2O to give CH3Re(NAd)2O (2a) and AdNH2. The resulting di(imido)oxo species can further react with another molecule of H2O to generate CH3Re(NAd)O2 (3a). The kinetics of these reactions have been studied by means of 1H NMR and UV-vis spectroscopies. The second-order rate constant for the reaction of 1a with H2O at 298 K in C6H6 is 3.3 L mol-1 s-1, which is much larger than the value 1 x 10(-4) L mol-1 s-1 obtained for the reaction between CH3Re(NAr)3 (1b, Ar = 2,6-diisopropylphenyl) and H2O in CH3CN at 313 K. Both 1a and 1b react with H2S to produce the rhenium(VII) sulfide, (CH3Re(NR)2)2(mu-S)2 (4a, R = Ad; 4b, R = Ar), with second-order rate constants of 17 and 1.6 x 10(-4) L mol-1 s-1 in C6H6 and CH3CN, respectively. Complex 4b has been structurally characterized. The crystal data are as follows: space group C2/c, a = 30.4831 (19) A, b = 10.9766 (7) A, c = 18.1645 (11) A, beta = 108.268(1) degrees, V = 5771.5 (6) A3, Z = 4. The reaction between CH3Re(NAr)2O (2b) and H2S also yields the dinuclear compound 4b. Unlike 1b, 1a reacts with aniline derivatives to give mixed imido rhenium complexes.  相似文献   

3.
The title compound,N,N′-bis-[3-chloro-5-S-(l-menthyloxy)-2(5H)-4-furanon-yl]-propane-1,3-diamine(C31H48Cl2N2O6,Mr = 615.61),has been synthesized and characterized by IR,1H NMR,MS,elemental analysis and single-crystal X-ray diffraction.The crystal crystallizes in the monoclinic system,space group C2 with a = 16.1091(4),b = 11.1880(3),c = 19.2854(5) ,β = 106.297(2)°,V = 3336.12(15) 3,Z = 4,Dc = 1.226 mg/m3,μ = 0.237 mm-1,F(000) = 1320,the final R = 0.0531 and wR = 0.0700 for 2760 observed reflections(I > 2σ(I)).X-ray analysis reveals that the title compound possesses four rings:two chiral five-membered furanone rings and two six-membered cyclohexane rings with chair conformation,containing eight chiral centers:C2(S),C3(R),C5(R),C10(S),C18(S),C21(R),C22(S) and C25(R).The structure is stabilized by N-H…O hydrogen bonding interaction.  相似文献   

4.
Monoclinic FePb(4)Sb(6)S(14) phase, jamesonite, which is a candidate material as a S = 2 Haldane compound, has been synthesized by the direct reaction of elements under dry conditions with sealed evacuated quartz tubes. The congruent melting point was determined at 592 degrees C by DTA measurements. Shiny metallic gray needle crystals grow on the surface of bulk heated at 550 degrees C. The elongated direction of each needle crystal is parallel to the c-axis. The crystal structure refinement (P2(1)/a, a = 15.750(6) A, b = 19.125(3) A, c = 4.030(4) A, beta = 91.68(8) degrees, V = 1213(1) A(3), Z = 2, D(c) = 5.651 g/cm(3), R(1) = 3.16%) reveals the presence of two rod substructures elongated parallel to the c-axis. One is the lozenge-shaped Bi(2)Te(3)-type (or called SnS archetype), [Pb(4)Sb(6)S(13)]. The other is the novel single magnetic one-dimensional (1D) straight chain, [FeS(6)]. This compound shows intrinsic semiconductor behavior in the electric conductivity measurements. The optical band gap, 0.48 eV, is estimated by near-IR diffuse reflectance measurements. In the magnetic susceptibility measurements, this compound shows 1D-Heisenberg antiferromagnetic behavior with a broad peak at approximately 33.5 K, where Fe(2+) takes the high-spin state, t(2g)(4)e(g)(2). A possibility for the S = 2 Haldane system is discussed.  相似文献   

5.
合成了三氨基胍三硝基间苯二酚盐(TAGH)2(TNR)(TAG)三氨基胍;TNR:2,4,6-三硝基间苯二酚),并对其进行了元素分析及红外光谱表征.利用X射线单晶衍射分析测定了其晶体结构.该晶体属于单斜晶系,空间群为C2/c,晶体学数据为,a=2.2892(6)nm,b=1.2802(3)nm,c=1.3661(4)nm,β=111.174(5)°,V=3.7333(16)nm3,Z=8.该化合物是由二个C(N2H3)3+与一个(C6HN3O8)2相结合而成的离子型化合物.用差示扫描量热法、热重法和微商热重法研究了该化合物的热分解过程,研究结果表明,在10 K·min-1的升温速率下,该化合物只有一个剧烈的放热分解过程,该过程发生在450.1-477.7K之间,且分解产物主要是气体产物.  相似文献   

6.
The title compound (+)-((-hydroxybenzyl)phenylphosphinic acid (C13H13O3P, Mr = 248.20) has been synthesized and characterized by 31P NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 293(2) K indicates that the compound belongs to monoclinic system, space group C2 with cell parameters: a = 23.560(8), b = 6.947(2), c = 7.854(3) (A。), β = 91.273(6)°, V = 1285.2(7) (A。)3, Z = 4, Dc = 1.283 g/cm3, F(000) = 520 and ((MoK() = 0.207 mm-1. The number of independent reflections amounts to 1991, of which 1507 are observed reflections. The crystal structure has been determined by direct methods (SHELXL-97). The structure parameters are refined by full-matrix least-squares on F2 to R = 0.0437 and wR = 0.0893. The flack x parameter is - 0.0001. The absolute configuration of the (-carbon in the title compound is S.  相似文献   

7.
The title compound, spiro[1-bromo(S)-4-(R)-hydroxy-5-oxa-6-oxo-bicyclo[3.1.0]-hxane-2,2'-(3'-diethyl-α-(S)-4'-Cl-benzyloxyphosphonyl-4'-(1R,2S,5R)-menthyloxybutyrolactone)] has been synthesized via the tandem asymmetric reaction and it crystallizes in a monoclinic system, space group P21 with a = 11.067(3), b = 12.484(2), c = 12.356(2)(A), β = 101.95°,C29H39BrC1O10P, Mr = 693.93, V= 1670.2(6) (A)3, Z= 2, Dc= 1.380 g/cm3, λ(MoKα) = 0.071073nm, μ = 1.410 mm-1, F(000) = 720, the final R = 0.0570 and wR = 0.0758 for 6190 observed reflections with I > 2σ(I). The structure is characterized by the special combination of biologic phosphonyl group and one cyclopropane as well as two butyrolactones. The intermolecular hydrogen bond between O(3)-H(3A)…O(10) in the crystal lattice has been observed.  相似文献   

8.
In this paper, we report the crystal structure and magnetic properties of the cyano-bridged gadolinium-tungstate bimetallic assembly, GdIII(DMF)6[WV(CN)8](DMF =N,N-dimethylformamide). X-Ray single crystal analysis shows that this compound crystallizes in the monoclinic system of space group P2(1)/c with cell constants a= 16.40(2)A, b= 11.08(1)A, c= 21.18(2)A, beta= 91.09(8) degrees, and Z= 4. The crystal consists of one-dimensional linear chains, in which [GdIII(DMF)6]3+ and [WV(CN)8]3- ions are linked in an alternating fashion. The magnetic data show that this compound is a paramagnet with an antiferromagnetic coupling of -0.58 cm-1 between GdIII(S= 7/2) and WV(S= 1/2).  相似文献   

9.
1INTRODUCTION'TheclusterscontainingMo--SorW--Shavebeenstudiedextensivelyfortheirimportantapplicationsinmanyfieldsll~43.Alongwith.thedevelopmentofrationaldesignedsynthesissuchasthe"UnitConstruction"utilizingwell-definedactivecom-poundsasbuildingblocks,binuclearsulfidecompoundsusedtodesignnewclustershavebeenpaidattentiontots'6itandalotofcompoundscontainingiM,S.O.--.J' (M=MoorW)coreshavebeenprepared['i.Inthispaper,thefirstexamplpofbitung-stencompoundwithtdtZ--ligands(Et.N),W,S.(tdt),,…  相似文献   

10.
合成了三氨基胍三硝基间苯二酚盐(TAGH)2(TNR) (TAG: 三氨基胍; TNR: 2,4,6-三硝基间苯二酚), 并对其进行了元素分析及红外光谱表征. 利用X射线单晶衍射分析测定了其晶体结构. 该晶体属于单斜晶系, 空间群为C2/c, 晶体学数据为, a=2.2892(6) nm, b=1.2802(3) nm, c=1.3661(4) nm, β=111.174(5)°, V=3.7333(16) nm3, Z=8. 该化合物是由二个C(N2H3)+3与一个(C6HN3O8)2-相结合而成的离子型化合物. 用差示扫描量热法、热重法和微商热重法研究了该化合物的热分解过程, 研究结果表明, 在10 K·min-1的升温速率下, 该化合物只有一个剧烈的放热分解过程, 该过程发生在450.1-477.7 K之间, 且分解产物主要是气体产物.  相似文献   

11.
1 INTRODUCTION Recently, for the fluorescent properties, Schiff base has been more and more important and widely studied in density optical memories, nonlinear op- tics (NLO), organic light-emitting diodes (OLED), polymer LED and electrogenerated chemilumines- cence (ECL)[1~5]. Thiosemicarbazones are a kind of Schiff bases with thiourea and good ligands easily chelating with transition metal ions. Although they have been studied extensively for a long time due to their chemical and b…  相似文献   

12.
A new three-dimensional hydroxide-arsenate compound called compound 2 has been synthesized by heating (in air) of the sarkinite phase, Mn(2)(OH)AsO(4) (compound 1), with temperature and time control. The crystal structure of this high-temperature compound has been solved by Patterson-function direct methods. A relevant feature of this new material is that it is actually the first member of the adamite-type family with mixed-valence manganese(II,III) and electronic conductivity. Crystal data: a = 6.7367(5) ?, b = 7.5220(6) ?, c = 9.8117(6) ?, α = 92.410(4)°, β = 109.840(4)°, γ = 115.946(4)°, P1?. The unit cell content derived from Rietveld refinement is Mn(8)(O(4)H(x))(AsO(4))(4). Its framework, projected along [111], is characterized by rings of eight Mn atoms with the OH(-)/O(2-) inside the rings. These rings form an almost perfect hexagonal arrangement with the AsO(4) groups placed in between. Bond-valence analysis indicates both partial deprotonation (x ? 3) and the presence of Mn in two different oxidation states (II and III), which is consistent with the electronic conductivity above 300 °C from electrochemical measurements. The electron paramagnetic resonance spectra of compound 1 and of its high-temperature form compound 2 show the presence of antiferromagnetic interactions with stronger magnetic coupling for the high-temperature phase. Magnetization measurements of room-temperature compound 1 show a complex magnetic behavior, with a three-dimensional antiferromagnetic ordering and magnetic anomalies at low temperatures, whereas for compound 2, an ordered state is not reached. Magnetostructural correlations indicate that superexchange interactions via oxygen are present in both compounds. The values of the magnetic exchange pathways [Mn-O-Mn] are characteristic of antiferromagnetic couplings. Notwithstanding, the existence of competition between different magnetic interactions through superexchange pathways can cause the complex magnetic behavior of compound 1. The loss of three-dimensional magnetic ordering by heating of compound 1 could well be based on the presence of Mn(3+) ions (d(4)) in compound 2.  相似文献   

13.
With an aim to discover novel AHAS inhibitors,the title compound (S)-ethyl-2(2-methoxy-phenylsulfenamido)-3-(1H-indol-3-yl)propanoate (C 21 H 22 N 2 O 4 S,M r=398.47) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis.The crystal belongs to orthorhombic,space group P2 1 2 1 2 1 with a=8.078(2),b=12.824(4),c=18.788(6),V=1946.2(10) 3,Z=4,F(000)=840,D c=1.360 mg/m 3,μ=0.197 mm-1,the final R=0.0433 and wR=0.1035 for 3075 observed reflections with I > 2σ(Ⅰ).The absolute structure Flack parameter X of this compound is 0.00(8).A total of 14375 reflections were collected,of which 3431 were independent (R int=0.0437).X-ray analysis reveals that the crystal structure involves two intermolecular N-H···O and one N-H···S intermolecular hydrogen bonds with the neighboring molecules.The crystal structure was compared with our previously reported (S)-methyl 2-(4-R-phenylsulfonamido)-3-(1H-indol-3-yl)propanoate (R=H(1) and Cl(2)),which provided some useful information of these compounds.  相似文献   

14.
The title compound N-tert-butyl-N-(4-methyl-1,2,3-thiadiazole)-5-yl-N'-(4-me-thyl-1,2,3-thiadiazole)-5-formyl-N'-3,5-dichloropyrid-2-yl-diacylhydrazines (C18H17Cl2N7O3S2, Mr = 514.41) has been synthesized by the reaction of N-tert-butyl-N'-3,6-dichloropyridine-2-formyl hydrazine with 4-methyl-1,2,3-thiadiazole-5-carbonyl chloride and triethylamine, and its structure was characterized by 1H NMR, HR MS, and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic, space group C2/c with a = 27.726(8), b = 11.045(3), c = 14.507(4), β = 96.758(4)°, Z = 8, V = 4412(2) 3, Dc = 1.549 g/cm3, μ = 0.521 mm-1, F(000) = 2112, R = 0.0405 and wR = 0.1153. X-ray analysis indicates that all rings are non-planar in this molecule. The bioassay results indicate that both the title compound and the positive control RH-5992 have weak fungicide activities, while the title compound has good insecticidal activity against Plutella xylostella L. and no insecticidal activity against Culex pipiens pallens.  相似文献   

15.
Wang XY  Sevov SC 《Inorganic chemistry》2008,47(3):1037-1043
Three hybrid organic-inorganic coordination polymers with benzenepentacarboxylate (BPCA) linkers, [Co3(C6H(COO)5)(OH)(H2O)3] (1-Co), [Zn3(C6H(COO)5)(OH)(H2O)3] (2-Zn), and [Co5(C6H(COO)5)2(H2O)12].(H2O)12 (3-Co), were synthesized hydrothermally and were characterized structurally and magnetically. 1-Co and 2-Zn are isostructural [C2/c; Z=8; 1-Co, a=19.5350(6) A, b=10.4494(4) A, and c=13.2353(5) A, beta=97.2768(8) degrees; 2-Zn, a=19.5418(9) A, b=10.3220(10) A, and c=13.4660(10) A, beta=98.455(10) degrees] with three-dimensional structures that contain [M6] secondary building units bridged by BPCA ligands. A different cobalt-based compound, 3-Co, forms at lower pH and lower reaction temperature. Its structure [P21/c; Z=2; a=12.6162(2) A, b=11.3768(2) A, and c=15.3401(3) A, beta=91.539(1) degrees] is a more loosely packed framework with free (noncoordinated) carboxylic groups pointing at water-filled cavities in the framework. The magnetic phase diagram of 1-Co established through detailed magnetic measurements shows a metamagnetic transition below TN=3.8 K. The less-packed compound 3-Co, on the other hand, remains paramagnetic above 1.9 K. The three compounds are the first examples of coordination polymers with benzenepentacarboxylate linkers and fill the gap of coordination polymers involving benzenepolycarboxylate linkers of the general type C6H6-n(COOH)n, where n=2-6.  相似文献   

16.
1 INTRODUCTION a-Hydroxyphosphonic acids and their esters are known to possess broad-based physiological activities and there is close links between biological efficacy and stereochemistry[1~3]. Optical active a-hydroxyphosphonic esters can also serve as useful precursors in organic synthesis[4, 5]. Here we will report the synthesis of optical active a-hydroxyphosphinic acid, (+)-(a-hydroxybenzyl)- phenylphosphinic acid and its crystal structure and the absolute configuration of its a-ca…  相似文献   

17.
In the ethanol solvent, a nickel(Ⅱ) complex Ni(C12H10N2O2S)2 upon reaction of 2'-(2-thienylidene)-hydroxybenzoylhydrazide with nickel acetate was synthesized, and its structure was characterized by IR, UV, elemental analysis and X-ray diffraction analysis. The crystal belongs to monoclinic system, space group C2/c with a = 22.052(3), b = 5.9681(6), c = 18.522(2) (A), β = 110.679(4)° , V = 2280.6(4) (A)3, Z = 4, Mr = 551.27, μ = 1.606 mm-1, Dc = 1.075 g/cm3, F(000) = 1136 and Rint = 0.0556. The nickel(Ⅱ) atom in the compound is four-coordinated with two nitrogen atoms from amide and two oxygen atoms from keto group. The biological activities have been measured, show- ing the compound exhibits better anti-bacterial activity than the ligand.  相似文献   

18.
A novel compound N-(4-methylbenzyl)-4-(3-fluorophenyl)-4-piperidinol hydrochloride has been synthesized and its structure (C19H23ClFNO, Mr = 335.83) was characterized by elemental analysis, IR, ^1H NMR, MS and single-crystal X-ray diffraction analyses. The crystal belongs to the triclinic system, space group P1 with a = 7.2163(6), b = 10.7905(9), c = 12.2651(10) A, α = 109.576(2),β = 98.407(2),γ= 95.956(2)°, V= 878.14(13)A3, Z = 2, Dc = 1.270 g/cm^3,μ = 0.231 mm^-1, F(000) = 356, S = 1.100, the final R = 0.0525 and wR = 0.1425 for 3206 unique reflections (Rint = 0.0140) with 2736 observed ones (I 〉 2σ(I)). The piperidine ring exhibits a chair conformation. The dihedral angle made by the methyl- and fluoro-substituted benzene rings is 66.84(7)°. There are some intra- and intermolecular hydrogen bonding interactions among the molecules, which stabilize the whole crystal structure. The preliminary biological activity tests indicate good herbicidal activity for the title compound, in particular against the roots of some tested plants (such as Brassica campestris L. and Echinochloa crusgallis L.).  相似文献   

19.
The compound 3,6-bis(4-methyl-1,2,3-thiadiazol-5-yl)-1,2,4-triazolo[3,4-b][1,3,4] thiadiazole(C9H6N8S3,Mr = 322.40) has been synthesized by the reaction of 4-amino-3-(4-methyl-1,2,3-thiadiazolyl)-5-mercapto-1,2,4-triazole with 4-methyl-1,2,3-thiadiazol-5-carboxylic acid and phosphorus oxychloride,and its structure was characterized by IR,1H NMR,EI-MS,elemental analysis and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic,space group C2/c with a = 2.0053(4),b = 1.3081(3),c = 1.0556(2) nm,β = 112.69(3)°,Z = 4,V = 2.5548(9) nm3,Dc = 1.676 g/cm3,μ = 0.582 mm-1,F(000) = 1312,R = 0.0546 and wR = 0.1523.X-ray analysis indicates that all rings are essentially planar in this molecule,and an intermolecular hydrogen bond C(9)-H(9)…N(2) and weak intramolecular interactions between S(1)…N(7),S(3)…N(1) and S(2)…N(4) are observed.  相似文献   

20.
A new iron(III) arsenate templated by ethylenediamine, (C2H10N2) [Fe(HAsO4)2(H2AsO4)](H2O), has been prepared by hydrothermal synthesis. The unit-cell parameters are a = 8.705(3) A, b = 16.106(4) A, c = 4.763(1) A, beta = 90.63(3) degrees; monoclinic, P2(1) with Z = 2. The compound exhibits a chain structure along the c-axis with the ethylenediammonium cations as counterion. The chains show isolated FeO6 octahedra with two HAsO4 and one H2AsO4 tetrahedra per FeO6 octahedron. The ESR spectrum at 5.0 K is isotropic with a g-value of 2.0, which remains practically unchanged at room temperature. Magnetic measurements indicate the presence of antiferromagnetic interactions. A value of -0.835 K for the J-exchange parameter has been calculated by fitting the magnetic data to a model for antiferromagnetic chains of spin S = 5/2.  相似文献   

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