首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
3.
4.
The reaction of N-n-Bu4MnO4 with Mn(Oac) 2 · 4H2O and butenoic acid in nonaqueous solvents leads to the formation of the complex [Mn3O(O2CCH = CHCH3) 6(py) 3] ClO4 · py (1). The crystal structure was determined.The complex crystallizes in hexagonal, space group P63/m, unit cell parameters, a = 1. 2456(1)nm, b = 1. 2456(1) nm, c = 1. 8741(1) nm, V=2. 5181(3) nm3, Z =2, and final R1 =0. 0565, wR2 =0. 1465. Variable tem-perature solid tate magnetic susceptibility study shows that the complex [Mn3O(O2CCH = CHCH3)6(py)3] ClO4 (2) has an antiferromagnetic exchange interaction.  相似文献   

5.
Trans,trans-[MoX2py4][MoX4py2] (X = Cl, A; Br, B; py = pyridine, C5H5N) are the side products of reaction of between (NH4)2[MoX5 · H2O] (X = Cl,Br) with pyridine diluted with methanol. Both trans,trans-[MoX2py4][MoX4py2] are monoclinic, P21/n space group, with z = 2 and: a = 12.568(1), b = 9.430(1), c = 14.952(1) Å and β = 100.81(1)° (A); a = 12.551(2), b = 9.533(2), c = 15.366(2) (Å) and β = 99.35(1) (B). Cations and anions are located on the symmetry centers and have eclipsed conformation of the trans located pyridine ligands. Average Mo? X and Mo? N (pyridine) bonds are; (cation) 2.41, 2.21 Å (A); 2.54, 2.21 Å (B); (anion) 2.44, 2.20 Å (A); 2.58, 2.20 Å (B). Anionic part of the compounds can be oxidised by bromine to trans-MoX4py2, which precipitates from the solution. Cation can be isolated from the solution in the form of trans-[MoX2py4]Br3 (X = Cl, Br). The compounds were also characterised by chemical analysis, infrared spectroscopy and conductivity measurements.  相似文献   

6.
7.
The reaction of [Mn3O(OAc)6(py)3] with 1,1,1-tris(hydroxymethyl)ethane (H3thme) gives the Mn(IV)3Mn(III)4Mn(II)2 complex [Mn9O7(OAc)11(thme)(py)3(H2O)2], which has an S = 17/2 ground state and displays strong out-of-phase signals in ac susceptibility studies that establish it as a new class of single-molecule magnet.  相似文献   

8.
9.
10.
The title complex, catena‐poly[di‐μ3‐acetato‐κ6O:O:O′‐tetra‐μ2‐acetato‐κ4O:O4O:O′‐diaquabis(pyridine‐κN)trimanganese(II)], [Mn3(CH3COO)6(C6H5N)2(H2O)2]n, is a true one‐dimensional coordination polymer, in which the MnII centres form a zigzag chain along [010]. The asymmetric unit contains two metal centres, one of which (Mn1) lies on an inversion centre, while the other (Mn2) is placed close to an inversion centre on a general position. Since all the acetates behave as bridging ligands, although with different μ2‐ and μ3‐coordination modes, a one‐dimensional polymeric structure is formed, based on trinuclear repeat units (Mn1...Mn2...Mn2′), in which the Mn2 and Mn2′ sites are related by an inversion centre. Within this monomeric block, the metal–metal separations are Mn1...Mn2 = 3.36180 (18) Å and Mn2...Mn2′ = 4.4804 (3) Å. Cation Mn1, located on an inversion centre, displays an [MnO6] coordination sphere, while Mn2, on a general position, has a slightly stronger [MnO5N] ligand field, as the sixth coordination site is occupied by a pyridine molecule. Both centres approximate an octahedral ligand field. The chains are parallel in the crystal structure and interact via hydrogen bonds involving coordinated water molecules. However, the shortest metal–metal separation between two chains [5.3752 (3) Å] is large compared with the intrachain interactions. These structural features are compatible with a single‐chain magnet behaviour, as confirmed by preliminary magnetic studies.  相似文献   

11.
The preparation and properties of [Mn(4)O(3)(O(2)CPh-R)(4)(dbm)(3)] (R = H, p-Me, p-OMe, and o-Cl; dbm(-) is the anion of dibenzoylmethane) single-molecule magnets (SMMs) with virtual C(S) symmetry are reported. They were prepared by controlled potential electrolysis in 26-80% yields. The structures comprise a distorted-cubane core of virtual C(S) symmetry, in contrast to the other, more common complexes of this type with virtual C(3)(V) symmetry. Solid-state magnetic susceptibility data establish the complexes have S = 9/2 ground-state spins, and ac susceptibility studies indicate they are single-molecule magnets (SMMs). Magnetization vs dc field sweeps below 1.00 K reveal hysteresis loops confirming a SMM, with a very large step at zero applied field diagnostic of fast quantum tunneling of magnetization (QTM) through the anisotropy barrier. The fast QTM rate suggested a significant rhombic ZFS parameter E, as expected from the low (virtual C(S)) symmetry. This was confirmed by high-frequency electron paramagnetic resonance spectroscopy on polycrystalline and single-crystal studies. The results confirm the importance of symmetry on the QTM rates.  相似文献   

12.
Preparation and Crystal Structure of (NH4)2[V(NH3)Cl5]. The Crystal Chemistry of the Compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2, and M2VXCl5 with M = K, NH4, Rb, Cs and X ? Cl, O (NH4)2[V(NH3)Cl5] crystallizes like [Rh(NH3)5Cl]Cl2 in the orthorhombic space group Pnma with Z = 4. The compounds are built up by isolated NH4+ or Cl? and complex MX5Y ions. The following distances have been observed: V? N: 213.8, V? Cl: 235.8–239.1, Rh? N: 207.1–208.5, Rh? Cl: 235.5 pm. Both structures differ from the K2PtCl6 type mainly in the ordering of the MX5Y polyhedra. The compounds M2VCl6 and M2VOCl5 with M = K, NH4, Rb, and Cs crystallize with exception of the orthorhombic K2VOCl5 in the K2PtCl6 type. The ordering of the MX5Y polyhedra in the compounds (NH4)2[V(NH3)Cl5], [Rh(NH3)5Cl]Cl2 and K2VOCl5 enables a closer packing.  相似文献   

13.
0引言苯羟乙酸[C6H5CH(OH)CO2H,简写成H2PHAc]是一种杀虫剂,和水杨酸相似,具有抑制微生物繁衍的作用。苯羟乙酸也是一种重要的分析试剂,已用于超痕量钼、金的示波极谱分析[1,2]。苯羟乙酸是一种α鄄羟基酸,它具有羧基和羟基,是双功能基配体,羧基和羟基可分别脱去氢,因此,可以有  相似文献   

14.
Pyridine Adducts of the Gold Halides. 1. Synthesis and Structure of [Hpy][AuCl4], AuC13 · py, [AuCl2(py)2]Cl · H2O, and [AuCl2(py)2] [AuCl2] HAuCl4 reacts with pyridine in aqueous solution to form sparingly soluble [Hpy] [AuCl4]. This goes into solution as [AuCl2(py)2]+ on adding an excess of pyridine. [Hpy][AuCl4] decomposes above 195°C to HCl and AuCl3 · py, which can also be obtained from NaAuCl4 and pyridine. AuCl2 · py is formed by the reaction of AuCl2 · S(CH2C6H4)2 with pyridine in CHCl3. According to the vibrational spectrum the complex is built up of trans[AuCl2(py)2]+ cations and [AuCl2]? anions. The IR spectra of [Hpy][AuCl4], AuCl3 · py, and [AuCl2(py)2]Cl · H2O are discussed and assigned with respect to the crystal structures. [Hpy][AuCl4] crystallizes monoclinic in the space group C2/m. In its structure alternating layers of [Hpy]+ cations and [AuCl4]? anions are observed. The monoclinic AuCl3 · py (space group C2/c) consists of molecular complexes, wherein the gold atom is surrounded by three Cl atoms and one pyridine molecule in a square planar arrangement. The coordination is completed to an elongated octahedron by two more distant Cl atoms of neighbouring complexes. [AuCl2(py)2]Cl · H2O crystallizes in the monoclinic space group P21/n. It forms planar trans[AuCl2(py)2]+ cations, weakly coordinated with an additional Cl? ion and one H2O molecule. The Au? Cl bond lengths in the complexes under investigation are in the range of 227 to 229 pm, the Au? N distances are between 197 and 199 pm.  相似文献   

15.
16.
A layered mixed-valence manganese complex, [Mn(II)(2)(bispicen)(2)(mu(3)-Cl)(2)Mn(III)(Cl(4)Cat)(2)Mn(III)(Cl(4)Cat)(2)(H(2)O)(2)](infinity), is synthesized and characterized structurally. It displays a slow magnetic relaxation and hysteresis effect.  相似文献   

17.
18.
19.
20.
This paper reports on a procedure for the synthesis of the compound [RuNO(NH3)3Cl(H2O)]Cl2. The complex was studied by IR spectroscopy and X-ray phase and X-ray diffraction analyses. Crystal data for RuCl3N4O2H11: a = 13.151(2), b = 6.852(1), c = 10.361(1) , V = 933.6(2) 2, space group Pna2 1 , Z = 4, d calc = 2.181 g/cm3, d exp = 2.178 g/cm3. The structure consists of the [RuNO(NH3)3Cl(H2O)]2+ complex cations and Cl anions. The compound crystallizes as small orange red isometric orthorhombic crystals well soluble in water and insoluble in concentrated hydrochloric acid and organic solvents and is stable when stored in air.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号