Synthesis and Crystal Structure of a One-dimensional Mn(Ⅱ) Coordination Polymer with 1,3-bis(4-pyridyl)propane

A new 1D zigzag chain coordination polymer, { [Mn（bpp）（bac）2]·（CHaCN）}n 1 （bpp = 1,3-bis（4-pyridyl）propane, Hbac = benzoylacetone）, has been synthesized and characterized by FT-IR spectroscopy, thermal analysis and X-ray single-crystal diffraction. In the molecular structure, all Mn atoms locate in an octahedral geometry. The guest CH3CN molecules are included in the 1D channels of the 3D packing structure of 1. Crystal data： C35H35MnNaO4, Mr = 616.60, monoclinic, space group P211c, a = 17.691（4）, b = 18,955（4）, c = 9.712（6） A, β = 93.91（3）°, V = 3249.31（1） A^3, Z = 4, Dc = 1.260 g/cm^3, F（000） = 1292, 20max = 54.9°, μ = 0.447 mm^-1, the final S = 1.020, R = 0.0693 and wR = 0.1497.

Syntheses and Crystal Structures of Two Co(II) Coordination Polymers with 4,4'-(Hexafluoroisopropylidene)bis(benzoic acid)

Two new one-dimensional zigzag chain coordination polymers, [Co（hfipbb）（2,2＇- bpy）（H2O）2]n 1 and [Co（hfipbb）（1,10-phen）（H2O）], 2, have been synthesized under hydrother- mal reactions from COCl2.6H20, 4,4＇-（hexafluoroisopropylidene）bis（benzoic acid） and 2,2＇ -bipyridine or 1,10-phenanthroline ligands, respectively. Single-crystal X-ray analyses revealed that the zigzag chains of 1 and 2 are linked into three-dimensional supramolecular networks by both O-H…O hydrogen-bonds and π…π stacking interactions. Crystal data for 1： CzTHajCoF6N2Os Mr = 641.38, orthorhombic, space group Pnna, a = 9.3820（19）, b = 27.366（6）, c = 10.106（2）A, V = 2594.8（9）A3, Z = 4, Dc = 1.642 g/cm3, F（000） = 1300,/t = 0.752 mm-l, R = 0.0311 and wR = 0.0924. Crystal data for 2： C29H18CoF6N2O5, Mr = 647.38, monoclinic, space group P21/n, a = 7.7626（16）, b = 29.446（6）, c = 11.281（2）A,β= 93.98（3）°, V= 2572.3（9）A3, Z = 4, Dc = 1.672 g/cm3, F（000） = 1308,μ= 0.757 mm-1, R = 0.0403 and wR = 0.0820.

Study on preparation technique and properties of magnetostrictive epoxy bonded Tb_(1–x)Pr_x(Fe_(0.4)Co_(0.6))_(1.93) composites

The magnetic and magnetostrictive properties of epoxy bonded Tb1-xPrx（Fe0.4Co0.6）1.93 （0.85≤x≤1.00） composites, prepared with different epoxy proportions using cold compression-molding technique, were investigated. It is found that the optimal conditions were with a compaction pressure of 100 MPa and a mass ratio of resin to powder of 5：100. The Tb0.1Pr0.9（Fe0.4Co0.6）1.93 composite rod had a high magnetostriction of 770 ppm at an applied magnetic field of 960 kA/m, whereas the Pr（Fe0.4Co0.6）1.93 composite reached 500 ppm at 400 kA/m. The good magnetostrictive properties of Pr（Fe0.4Co0.6）1.93 composite at low-field （≤400 kA/m） could be explained by its low anisotropy. These results indicated that the epoxy bonded Tb1-xPrx（Fe0.4Co0.6）1.93 rod samples for high Pr content of x=0.9-1.0 were of practical value.

Syntheses and Crystal Structures of Two One-dimensional Coordination Polymers Constructed from a Flexible Hinge-like Ligand

By using the flexible hinge-like ligand 2,2＇-bis（3-hydroxy-l,4-naphthoquinone） （H2bhnq）, two isomorphous one-dimensional zigzag chain coordination polymers have been obtained. Single-crystal X-ray analyses revealed that the metal centers in these two complexes are distorted octahedra involving four oxygen atoms of two bhnq2 anions, and two oxygen atoms of two DMF molecules situated in trans positions to one another. Crystal data for [Mn（bhnq）（DMF）2]n 1： C26H22MnN2O8, Mr = 545.40, monoclinic, space group C2/c, a = 14.936（3）, b = 10.362（2）, c = 15.901（3）A., β = 99.86（3）°, V = 2424.7（8）A3, Z = 4, Dc = 1.494 g/cm^3, F（000） = 1124,μ = 0.599 mm^-1, final GOOF = 1.025, R = 0.0654 and wR = 0.1537. Crystal data for [Cd（bhnq）（DMF）2]n 2： C26H22CdN2O8, Mr = 602.86, monoclinic, space group C2/c, a = 14.839（3）, b = 10.493（2）, c = 16.034（3）A, β = 99.40（3）°, V = 2463.1（9）A^3, Z = 4, Dc = 1.626 g/cm^3, F（000） = 1216,μ = 0.941 mm^-1, final GOOF = 1.069, R = 0.0358 and wR = 0.0944.

Syntheses and Crystal Structures of Two Zn(Ⅱ) Coordination Polymers Constructed with 4,4'-(Dihydroxymethylene)dibenzoic Acid

Two new isomorphous metal-organic coordination polymers, [Zn（dhmdb）（2,2＇- bpy）]n 1 and [Zn（dhmdb）（1,10-phen）]n 2, have been obtained under hydrothermal reactions from 4,4＇-（dihydroxymethylene）dibenzoic acid （H2dhmdb）, Zn（NO3）2·6H2O and 2,2＇-pyridine or 1,10- phenanthroline, respectively. Compounds 1 and 2 have been characterized by FT-IR spectroscopy, thermal analysis and single-crystal X-ray diffraction. The zigzag chains of 1 and 2 are linked into three-dimensional supramolecular networks by both O–H…O hydrogen bonds and π…π stacking interactions. Crystal data for 1： ZnC25H18N2O6, Mr = 507.78, orthorhombic, space group Pbca, a = 14.031（3）, b = 10.826（2）, c = 27.343（6）, V = 4153.5（14）3, Z = 8, Dc = 1.624 g/cm3, F（000） = 2080, μ = 1.231 mm-1, R = 0.0699 and wR = 0.1829. Crystal data for 2： ZnC27H18N2O6, Mr = 531.80, orthorhombic, space group Pbca, a = 13.796（3）, b = 10.809（2）, c = 28.612（6）, V = 4266.8（15）3, Z = 8, Dc = 1.656 g/cm3, F（000） = 2176, μ = 1.203 mm-1, R = 0.0454 and wR = 0.1399.

Synthesis and Crystal Structure of a Tetranuclear Cu(Ⅰ) Complex with Vinylidenebis(diphenylphosphine)

The vinylidenebis（diphenylphosphine） （vdpp） reacts with CuBr to give a tetranuclear complex, [Cu4（μ3-Br）2（μ2-Br）2（μ2-vdpp）2（CH3CN）2]·（CH3CN）2 1. The title complex has crystallo- graphically imposed centrosymmetry and presents a CuaBr4 core with distorted stair-like structure. All copper（I） atoms in 1 assume distorted tetrahedral coordination geometry. The distance of 2.7745（11） A between the two copper centers indicates the presence of ligand-supported Cu…Cu interactions. Crystal data for 1： C_60H_56Br_4Cu_4N_4P_4, Mr= 1530.77, triclinic, space group P1, a = 11.6593（9）, b = 11.7181（9）, c = 13.8711（11） А, a = 110.1020（10）, β = 102.0050（10）, γ = 109.8040（10）°, V = 1557.5（2） А^3, Z = 1, Dc = 1.632 g/cm^3, F（000） = 760, λ= 0.71073А, T = 298（2） K, 2θmax = 50.04°,μ= 4.056 mm^-1, S = 1.181, R = 0.0507 and wR = 0.1025.

A One-dimensional Pseudo-helical Coordination Polymer with 4,4′-(Hexafluoroisopropylidene)bis(benzoic acid)

The title complex [Zn2（hfipbb）2（2,2′-bpy）2], 1 has been hydrothermally synthesized from Zn（NO3）2·6H2O, 4,4′-（hexafluoroisopropylidene）bis（benzoic acid） and 2,2′-bipyridine. Singlecrystal X-ray analysis reveals that 1 presents a one-dimensional coordination polymer with pseudo-helical chain structure. Two Zn（Ⅱ） atoms in an unsymmetrical unit of 1 adopt distorted octahedral and square-pyramidal coordination geometries, respectively. The packing of parallel chains gives a three-dimensional supramolecular network supported by π-π stacking interactions. Crystal data： C54H32F12N4O8Zn2, Mr = 1223.58, monoclinic, space group P2 1/c, a = 27.557（6）, b = 16.751（3）, c = 11.350（2） A, β= 99.21（3）°, V= 5171.5（18） A^3, Z= 4, Dc = 1.572 g/cm^3, F（000） = 2464, μ= 1.030 mm^-1, the final R = 0.0552 and wR = 0.1070 for 6631 observed reflections （I〉 2σ（I））.

Nucleation undercooling, solidification structures and magnetic properties of Nd_9Fe_(85–x)Ti_4C_2B_x (x=10–15) magnetic alloys

Nd_9Fe_（85–x）Ti_4C_2B_x（x=10–15） magnetic alloys were investigated by differential thermal analysis and X-ray diffraction analysis. The results showed that with the B content increasing from 10 at.% to 15 at.%, the liquidus temperatures TL of the alloys decreased from 1498.5 to 1472.5 K; the solidus temperatures TS of them increased from 1353.2 to 1358.3 K; and the nucleation undercooling of the alloy melts cooled at the rate of 40 K/min decreased from 122.8 to 95.9 K, resulting in the solidification structures consisting of Nd_2Fe_（14）B, Fe_3B, α-Fe, Nd1.1Fe4B4 and TiC nanocrystallines. Furthermore, the Nd_9Fe_（85–x）Ti_4C_2B_x（x=11, 13, 15） bulk alloys in sheet form with the thickness of 0.7 mm were prepared by copper mold suction casting and their solidification characteristics and solidification structures under sub-rapidly cooling rate were investigated. The results showed that partially amorphous structures were obtained in the as-cast bulk alloys and the amount of amorphous decreased with the increase of the B content. By annealing the as-cast bulk alloys at 923 K for 10 min, the nanocomposite microstructures composed with Nd_2Fe_（14）B, Fe_3B and α-Fe nanocrystallines, which showed a single-phase hard magnetic behavior and enhanced magnetic properties, were achieved.

Microstructure evolution and magnetic properties of the Nd_9Fe_(81–x)Ti_4C_2Nb_4B_x(x=11, 13, 15) bulk magnets prepared by copper mold suction casting

The bulk nanocomposite magnets of Nd9Fes1-xTi4C2Nb4Bx （x= 11, 13, 15） in sheet form with the thickness of 0.7 mm were prepared by copper mold suction casting and subsequently annealing. The microstructure evolution and magnetic properties of bulk magnets were studied. It was shown that the as-cast microstmcture ofbtflk alloys were composed ofNdEFe14B, a-Fe, FeaB crystalline phases and an amorphous matrix, and that the glass formability of alloy was improved with increasing the B content. The DSC analysis showed that the as-cast bulk alloys had the crystallization behavior of a two-step process. After annealing at the temperatures which was 40453 K higher than their onset temperatures of the second exothermic peak, Nd9Fe81 xTi4C2Nb4Bx （x=11, 13, 15） bulk alloys obtained a finely mixed structure which were composed of Nd2Fe14B, a-Fe, Fe3B, （Nb,Ti）C crystalline phases and a residual amorphous phase, whose magnetic properties were significantly enhanced. For the bulk magnets of Nd9Fes1-xTi4CENb4Bx （x=11, 13, 15）, the optimal magnetic properties of Br=0.63 T, iHc= 155.1 kA/m, （BH）max= 18.73 kJ/m3 could be achieved when x= 13 after annealing at 983 K for 10 min.

Synthesis and Crystal Structure of Rare Earth Metal Chlorides Bearing Bridged-lndenyl Ancillary Ligand

Two new rare earth metal chloride complexes supported by a bridged-indenyl ancillary ligand, [C9H6SiMe2- （CH2）2SiMeEC9H6]Ln（u-Cl）2Li（TMEDA） [Ln=Y （1）, Lu （2）], were synthesized via salt metathesis reaction. Reaction of C9H7SiMeE（CH2）ESiMeEC9H7 with 2 equiv, of n-butyllithium in hexane at room temperature afforded [C9H6SiMe2- （CHE）2SiMeEC9H6]Li2 as white powder in 95% isolated yield. Further treatment of [C9H6SiMe2（CHE）2SiMeE- C9H6]Li2 with anhydrous LnCl3 in 1 ： 1 molar ratio in THF/TMEDA at room temperature provided the bridged-indenyl rare earth metal chlorides 1 and 2 in 86%--89% isolated yields. Both complexes were characterized by FT-IR spectroscopy, NMR spectroscopy, elemental analysis, and X-ray single crystal structure analysis. The central metals in both complexes are eight-coordinated by two indenyl ligands in η^5-fashion, and two chlorine atoms to adopt a distorted tetrahedral geometry.

Magnetic transitions and magnetocaloric effect in MnAs_(0.9)P_(0.1)

The compound MnAs0.9P0.1 exhibits a multistep magnetic order-order transition from a helimagnetic γ-phase with Hα-type magnetic order to a ferromagnetic β-phase at 80 K and then to a helimagnetic α-phase at 203 K. The γ-β transition exhibits the characteristics of a first-order transition with a thermal hysteresis as large as 6 K, while the β-α transition is of second order with a thermal hysteresis smaller than 2 K and without magnetic hysteresis. With these two successive helimagnetism-related transitions, magnetic-entropy changes of -2.1 J/（kg·K） at 203 K for a field change from 0 to 5 T and 0.1 J/（kg·K） at 83 K for a field change from 0 to 1 T are obtained. Investigation of the magnetocaloric effect associated with a transition from Hα-type magnetic order to FM order may open a new route to explore candidates for magnetic refrigeration.