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1.
Reactions of rubidium or barium salts of the ortho‐selenostannate anion, [Rb4(H2O)4][SnSe4] ( 1 ) or [Ba2(H2O)5][SnSe4] ( 2 ) with Zn(OAc)2 or ZnCl2 in aqueous solution yielded two novel compounds with different ternary Zn/Sn/Se anions, [Rb10(H2O)14.5][Zn4(μ4‐Se)2(SnSe4)4] ( 3 ) and [Ba5(H2O)32][Zn5Sn(μ3‐Se)4(SnSe4)4] ( 4 ). 1 – 4 have been determined by means of single crystal X‐ray diffraction: 1 : triclinic space group lattice dimensions at 203 K: a = 8.2582(17) Å, b = 10.634(2) Å, c = 10.922(2) Å, α = 110.16(3)°, β = 91.74(3)°, γ = 97.86(3)°, V = 888.8(3) Å3; R1 [I > 2σ(I)] = 0.0669; wR2 = 0.1619; 2 : orthorhombic space group Pnma; lattice dimensions at 203 K: a = 17.828(4) Å, b = 11.101(2) Å, c = 6.7784(14) Å, V = 1341.5(5) Å3; R1 [I > 2σ(I)] = 0.0561; wR2 = 0.1523; 3 : triclinic space group ; lattice dimension at 203 K: a = 17.431(4) Å, b = 17.459(4) Å, c = 22.730(5) Å, α = 105.82(3)°, β = 99.17(3)°, γ = 90.06(3)°, V = 6563.1(2) Å3; R1 [I > 2σ(I)] = 0.0822; wR2 = 0.1782; 4 : monoclinic space group P21/c; lattice dimensions at 203 K: a = 25.231(5) Å, b = 24.776(5) Å, c = 25.396(5) Å, β = 106.59(3)°, V = 15215.0(5) Å3; R1 [I > 2σ(I)] = 0.0767; wR2 = 0.1734. The results serve to underline the crucial role of the counterion for the type of ternary anion to be observed in the crystal. Whereas Rb+(aq) stabilizes a P1‐type Zn/Sn/Se supertetrahedron in 3 like K+, the Ba2+(aq) ions better fit to an anionic T3‐type Zn/Sn/Se cluster arrangement as do Na+ ions. It is possible to estimate a radius:charge ratio for the stabilization of the two structural motifs.  相似文献   

2.
Y16I19C8B4 – a Yttrium Boride Carbide Halide Containing B2C4 Units The new compound Y16I19C8B4 was prepared from Y, YI3, C and B at 1050–1150 °C. The structure of a twinned crystal was determined by means of X-ray diffraction (space group P 1¯, a = 12.311(2) Å, b = 13.996(3) Å, c = 19.695(3) Å, α = 74.96(2)°, β = 89.51(2)°, γ = 67.03(2)°, Z = 2). Y16I19C8B4 is a semiconductor and contains nearly planar B2C4 units which are located in cages built up by 12 yttrium atoms. Assuming (B2C4)12–, these units can be regarded as isoelectronic with B2F4. The yttrium cages are connected via faces to form rods, which are surrounded by iodine atoms. Bridging iodine atoms connect the rods so that layers are formed. The characteristic twinning observed can be understood from the geometry of the crystal structure.  相似文献   

3.
Synthesis, Crystal Structures, and Spectroscopic Characterization of NiP4O11 and CaNiP2O7 From melts single crystals of NiP4O11 and CaNiP2O7 have been grown. These allowed refinement of the crystal structures (NiP4O11: C1¯, Z = 8, a = 12, 753(4)Å, b = 12.957(3)Å, c = 10.581(4)Å, α = 89.42(2)°, β = 116.96(2)°, γ = 90.20(2)°, R1 = 0.027, wR2 = 0.072 for 3058 Io > 2σ (Io), 3291 independent reflections, 290 parameters; CaNiP2O7: P1¯, Z = 2, a = 6.433(3)Å, b = 6.536(4)Å, c = 6.515(2)Å, α = 66.4(2)°, β = 87.5(2)°, γ = 82.7(2)°, R1 = 0.026, wR2 = 0.062 for 1624 Io > 2σ (Io), 2189 independent reflections, 101 parameter) and measurement of polarized electronic absorption spectra in the uv/vis/nir region (6000—32000 cm—1). NiP4O11 is isotypic to the series of ultraphosphates MP4O11 (M = Mn, Fe, Co, Cu, Zn, Cd) that exhibit a two‐dimensional network formed from ten‐membered phosphate rings. CaNiP2O7 completes the series of diphosphates AMP2O7 (A: Ca, Sr, Ba; M = Cr — Zn) and is isotypic to CaCoP2O7. Ni2+ ions in both phosphates show distorted octahedral coordination. The electronic transitions associated with the chromophores [Ni2+O6] are nicely reproduced by calculations within the framework of the angular overlap model (AOM). The parametrisation scheme leads to eσ, norm(2.0Å) = 3690 cm—1 and B = 896 cm—1 (C/B = 4.2) for CaNiP2O7 and eσ, norm(2.0Å) = 4150 cm—1 and B = 948 cm—1 (C/B = 4.5) for NiP4O11o(CaNiP2O7) = 6800 cm—1; Δo(NiP4O11) = 7100 cm—1).  相似文献   

4.
The crystal structure of [C10N2H10][ZnCl(HPO4)]2 contains corrugated tetrahedral layers with 63 topology. Charge balance is achieved by insertion of diprotonated 4,4′‐bipyridine between the layers. Crystal data: monoclinic, P21/n (no. 14), a = 4.8832(2) Å, b = 22.673(2) Å, c = 8.1643(4) Å, β = 104.02(1)°; V = 877.0(1) Å3; Z = 4; R1 = 0.041 and wR2 = 0.088 for 1836 reflections [I > 2σ(I)]. Tetrahedral layers are also observed in other organo‐ammonium templated compounds. However, their topologies are characterized by 4.82 nets. With the title compound a layered tetrahedral net with 63‐topology is reported for the first time.  相似文献   

5.
(Phenacetin)4·2I4·2H2O is triclinic, a = 13.641 (7), b = 12.807 (6), c = 7.201 (3) Å, α = 99.8 (4), b? = 86.5 (4), γ = 104.0 (5)°, P1 , Z = 1. The ordered crystal structure has been refined to RF = 0.050, using 4173 independent reflections measured on a four-circle diffractometer with MoKa (graphite monochromator) radiation. The crystals are composed of alternating positively and negatively charged slices; each positive slice contains a double layer of stacks of hemi-protonated phenacetin molecules which are H-bonded through their carbonyl groups (d(O - - - O) = 2.432 (4) Å) while each negative slice contains a single layer of I2?4-ions linked in chains along [100] through H-bonds to pairs of water molecules. The axes of the phenacetin stacks are parallel to the planes of the (I2?4·2H2O)-layers. The I2?4-ion is centro-symmetric and can be approximately represented as I?- - - I–I- - - I? (d(I? - - - I) = 3.404 (1) Å; d(I–I) = 2.774 (1) Å). The compound is a pseudo-type A basic salt.  相似文献   

6.
The Tetracyanoborates M[B(CN)4], M = [Bu4N]+, Ag+, K+ The tetracyanoborate anion is prepared for the first time as the tetrabutylammonium salt by the reaction of [NBu4]BX and BX3 (X = Br, Cl) in toluene with KCN. After purification and recrystallization of the product from CHCl3 colorless and needle size single crystals of [Bu4N][B(CN)4] are formed. After metathesis with AgNO3 the silver salt and subsequently with KBr the potassium salt is prepared. The three salts are characterized by single crystal X‐ray diffraction (Ag[B(CN)4] P 43m, a = 5.732(1) Å, V = 188.3 Å3, Z = 1, R1 = 0.75%; K[B(CN)4] I41/a, a = 6.976(1), c = 14.210(3) Å, V = 691.5 Å3, Z = 4, R1 = 1.90%; [Bu4N][B(CN)4] Pnna, a = 17.765(3), b = 11.650(2), c = 11.454(2) Å, V = 2370.5 Å3, Z = 4, R1 = 6.09%) and by NMR‐, IR‐, Raman‐ as well by UV‐spectroscopy.  相似文献   

7.
The preparation and X-ray crystal structures of the adducts of 10-thiabenzo-15-crown-5 and 10-selenabenzo-15-crown-5 with PdCl2 are reported. [PdCl2(C14H20O4S)2] (1): or-thorhombic, space group Pbca with cell dimensions of a=17.285(5), 6=8.354(3), c=21.689(4) A, K=3131.9 A3, Z=4;R=0.0330 for 2301 reflections with I > 3o(I), [PdCl2(C14H2oO4Se)2] (2): monoclinic, space group P21/n with cell dimensions of a=18.928(4), b=8.912(3), c=9.813(2) A, β=96.90(2)0, V=1643.4 A3, Z=2; R=0.0289 for 2617 reflections with I> 3σ(I), Both complexes are monomeric, square-planar palladiurn(Ⅱ) compounds with the Pd(Ⅱ) ion situating on a crystal-lographic inversion centre, and the crown ligands all adopt the axial coordination with the Pd-S bond of 2.3233(7) A and the Pd-Se bond of 2.4357(3) A. Their complexing characteristics are discussed in brief.  相似文献   

8.
Rare Earth Halides Ln4X5Z. Part 3: The Chloride La4Cl5B4 – Preparation, Structure, and Relation to La4Br5B4, La4I5B4 La4Cl5B4 is synthesized by reaction of LaCl3, La metal and boron in sealed Ta containers at 1050 °C < T < 1350 °C. It crystallizes in the monoclinic space group C2/m with a = 16.484(3) Å, b = 4.263(1) Å, c = 9.276(2) Å and β = 120.06(3)°. Ce4Cl5B4 is isotypic, a = 16.391(3) Å, b = 4.251(1) Å, c = 9.180(2) Å and β = 120.20(3)°. The La atoms form strings of trans-edge shared La octahedra, and the B atoms inside the strings form B4-rhomboids, which are condensed to chains via opposite corners. The Cl atoms interconnect the channels according to La2La4/2Cli−i6/2Cli−a2/2Cla−i2/2. The crystal structures of the bromide and the iodide are comparabel, however, the interconnection of the strings is different in the three structure types, as 14 Cl, 13 Br and 12 I atoms surround the La6 octahedra.  相似文献   

9.
The compounds [(n‐Bu)4N]3[MoS4Ag3Cl4] ( 1 ) and [Et4N]3[WOS3Cu3I4] ( 2 ) were synthesized and characterized. Compound 1 crystallizes in the rhombohedral system, space group R3c with a = 17.194(1), b = 17.194(1), c = 39.194(3)Å, Z = 6, V = 10034.7(11)Å3. Compound 2 crystallizes in the rhombohedral system, space group R3c with a = 14.461(2), b = 14.461(2), c = 34.952(2)Å, Z = 6, V = 6329.9(13)Å3. The X‐ray crystallographic structure determinations show that these two cluster compounds consist of a slightly distorted cubic core. Nonlinear optical (NLO) properties of these two clusters were investigated by using Z‐scan techniques with an 8 ns pulsed laser at 532 nm; both clusters exhibit strong nonlinear optical absorption effect (effective α2 = 1.18 × 10—10 m · W—1 for 1 and 1.0 × 10—10 m · W—1 for 2 ).  相似文献   

10.
Crystal structures of a series of manganese(I) complexes containing tripodal ligands were determined. For [η3-{CH3C(CH2PPh2)2(CH2SPh)-P,P′,S}Mn(CO)3]PF6 ( 1 ): a = 10.856(3) Å, b = 19.698(3) Å, c = 17.596(5) Å, β = 96.17(2)°, monoclinic, Z = 4, P21/c, R(Fo) = 0.068, Rw(Fo) = 0.055 for 3617 reflections with Io > 2σ(Io). For [η3-{CH3C(CH2PPh2)(CH2SPh)2-P,P′,S}Mn(CO)3]PF6 ( 2 ): a = 9.890(2) Å, b = 20.403(4) Å, c = 10.269(3) Å, β = 117.44(2)°, monoclinic, Z = 2, P2l, R(Fo) = 0.050, Rw(Fo) = 0.037 for 1760 reflections with Io > 2σ(Io). For [η3-{CH3C(CH2PPh2)2(CH2S)-P,P′,S}Mn(CO)3] ( 4 ): a = 8.191(7) Å, b = 10.495(3) Å, c = 19.858(6) Å, α = 99.61(2)°, β = 96.17(2)°, γ = 92.70(4)°, triclinic, Z = 2, P-I, R(Fo) = 0.048, Rw(Fo) = 0.039 for 2973 reflections with Io > 2σ(Io). There is no significant difference in the bond lengths of Mn-S bonds among three species in their crystal structures [2.325(2) Å in 1; 2.358(4) in 2; 2.380(2) in 4], but the better donating ability of thiolate in complex 4 appears on the lower frequencies of its carbonyl stretching absorptions.  相似文献   

11.
The structures of the Pd4(SBu)4(OAc)4 (I) and Pd6 (SBu)12 (II) palladium clusters are determined by the X-ray diffraction method. For cluster I: a = 8.650(2), b = 12.314(2), c = 17.659(4) Å, α = 78.03(3)°, β = 86.71(2)°, γ = 78.13(3)°, V = 1800.8(7) Å3, ρcalcd = 1.878 g/cm3, space group P \(\bar 1\), Z = 4, N = 3403, R = 0.0468; for structure II: a = 10.748(2), b = 12.840(3), c = 15.233(3) Å, α = 65.31(3)°, β = 70.10(3)°, γ = 72.91(3)°, V = 1767.4(6) Å3, ρ calcd = 1.605 g/cm3, space group P \(\bar 1\), Z = 1, N = 3498, R = 0.0729. In cluster I, four Pd atoms form a planar cycle. The neighboring Pd atoms are bound by two acetate or two mercaptide bridges (Pd…Pd 2.95–3.23 Å, Pd…Pd angles 87.15°–92.85°). In cluster II, the Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.09–3.14 Å, the PdPdPd angles being 118.95°–120.80°. The Pd atoms are linked in pairs by two mercaptide bridges. The formation of clusters I and II in solution is proved by IR spectroscopy and calorimetry. Analogous clusters are formed in solution upon the reaction of palladium(II) diacetate with thiophenol.  相似文献   

12.
The crystal structure of 2,3-benzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2-ene was de-termined,C_(14)H_(20)O_4Se,M_r:331.27,orthorhombic,Pbca,a=18.445(3),b=16.334(4),c9.232(2),V=2781.3 ~3,Z=8,Dx=1.582 Mg m~(-3),λ(Mo K_α)=0.71073 ,μ=26.77 cm~(-1),F(000)=1360,T=297 K,R=0.0329,R_w=0.0438 for 2192 reflections with I>3 σ(I).The crystal structure is closelyrelated to that of benzo-15-crown-5(at 123 K),whereas the molecular geometry of the two coronandsis different according to their torsion angles calculated and the shapes exhibited.  相似文献   

13.
A zinc(II) coordination polymer, [Zn4(o-bda)4(p-pbim)4] n (1) (p-pbim = 4-pyridylbenzimidazole, o-bda2? = o-phenylenediacetic acid dianion), has been synthesized by hydrothermal method and characterized by elemental analysis, IR, TG, photoluminescence and X-ray single crystal diffraction. Complex 1 crystallizes in a monoclinic system and space group P21 /n, with a = 14.231(3) Å, b = 16.257(4) Å, c = 16.794(4) Å, β = 100.262(1)°, and Z = 8; R 1 for 6475 observed reflections [I > 2σ(I)] was 0.0420. Complex 1 shows a bi-chain structure fabricated by the tetranuclear zinc unit. Two zinc(II) ions are five coordinate with distorted trigonal-bipyramid geometry; the other two zinc(II) ions are four coordinate with distorted tetrahedral geometry. Complex 1 builds the 1-D bi-chain structure with two different subrings A and B, which are 32-member and 14-member rings, respectively. There exists a 2-D supramolecular network linked by hydrogen-bonding interactions (2.695 and 2.807 Å). A 3-D supramolecular network is further constructed by non-covalent interactions between the 1-D bi-chain structure. The TG/DTG shows that the chain skeleton is thermally stable to 356°C. Blue fluorescent emission of the complex was determined at 404 nm in the solid state with short decay lifetime of 1.67 ns.  相似文献   

14.
Single-crystal X-ray diffraction experiments have been performed on diphenylvinylphosphine sulfide ( 1 ): C14H13PS, space group P 21/c, a = 10.186(1) Ǎ, b = 11.918(1) Å, c = 11.426 Å, β = 112.22(2)°, V = 1284.1(2) Å3, Z = 4, and diphenylvinylphosphine selenide ( 2 ): C14H13PSe, space group Pbca, a = 9.141 (3) Å, b = 16.458 (1) Å, c = 17.451 (1) Å, V = 2625.4 (9) Å3, Z = 8. The structures were solved by direct methods and were refined by full matrix least-squares calculations to R = 0.046 and Rw = 0.058 using 2554 unique reflections with I > 3σ(I) in the case of 1 , and to R = 0.052 and Rw = 0.065 using 1953 unique reflections with I > 3σ(I) in the case of 2 . In close analogy to the previously studied vinyl phosphine oxides both 1 and 2 were found to exist in the s-cis conformation with the pertinent CC PX dihedral angles equal to 12.5° and 2.9° for 1 and 2 , respectively.  相似文献   

15.
Abstract

Chemical preparations, crystal structures, thermal analyses, and IR spectroscopic studies are given for two new hydrogen phosphates templated by 4-amino-2,2,6,6-tetramethylpiperidine: (C9H22N2)2·(H2PO4)·(HPO4)·(F)·H2O (I) and (C9H22N2)·(H2PO4)2(II). The structures are determined by single crystal X-ray diffraction. Both compounds crystallize in the P21/c (N°14) monoclinic space group with the unit cell parameters: a = 14.856 (1) Å, b = 14.092 (2) Å, c = 14.7166 (9) Å, β = 118.434 (7)°, V = 2709.2 (4) Å 3, and Z = 4 for (I) and a = 9.803 (2) Å, c = 0.466 (2) Å, c = 15.640 (8) Å, β = 94.990 (4), V = 1598.68 (7) Å3, and Z = 4 for (II).

The structure of I, refined to R = 0.042 and Rw = 0.067 for 6009 reflections (I ≥ 2σ (I)), exhibits infinite inorganic chains ((H2PO4)·(HPO4)·(F)·H2O)4? linked together through weak hydrogen bonds to form layers onto which the diprotonated [C9H22N2]2 + amine molecules are anchored.

The structure of II, refined to R = 0.060 and Rw = 0.086 for 1435 reflections (I ≥ 2σ (I)), consists of (H2PO4)? (100) layers between which [C9H22N2]2+ cations are inserted. A network of hydrogen bonds connects the different components. IR spectra of I and II show the characteristic bands of amine groups and phosphate anions.  相似文献   

16.
Co6(μ3—Se)6 (PEt3)6·THF, MW = 1766.4, space group R3 , has the trigonal parameters, a= 11.890(2)° Å, α = 92.72(2)°, V = 1670.4 Å3, Z = 1. Mo Ka radiation, λ = 0.71073 Å, Dc = 1.749 g/cm3, μ = 59.18 cm?3, F(000) = 870, R = 0.058 and Rw= 0.067 for 1529 observed unique reflections with I>3α(I). The molecular structure consists of an idealized octahedral Co4—core. The Co—Co distances fall in the range of 2.909—2.912 Å.  相似文献   

17.
The coordination compounds [CdI2(4-MePy)2] (I) and [CdI2(4-MeQuin)2] (II) where Quin is quinoline have been synthesized, and their structure has been solved. Crystals of complex I are monoclinic, space group C2/c, a = 13.353(1) Å, b = 16.653(1) Å, c = 14.380 (1) Å, β = 103.17(1)°, V = 3113.5(4) Å3, ρcalcd = 2.425 g/cm3, Z = 8. Crystals of complex II are monoclinic, space group P21/c, a = 10.647(1) Å, b = 25.264(1) Å, c = 8.610(1) Å, β = 113.73(1)°, V = 2120.1(3) Å3, ρcalcd = 2.044 g/cm3, Z = 4. Polymer [CdI2(4-MePy)2] chains running in the direction [001] are formed in the structure of complex I. Each of the two crystallographically nonequivalent Cd(1) and Cd(2) atoms are octahedrally surrounded by the four iodine and two nitrogen atoms of the 4-MePy ligand. The Cd(1)?Cd(2) distance in a chain is 4.33 Å. The structure of complex II is built of [CdI2(4-MeQuin)2] discrete neutral clusters. The two iodine and two nitrogen atoms of the 4-MeQuin ligand participate in the coordination of the Cd2+ ion. The cadmium coordination polyhedron is a distorted tetrahedron (Cd-Iavg, 2.72 Å; Cd-Navg, 2.30 Å; angles N(I)CdN(I), 98.3–121.8°). The minimum and maximum values correspond to the ICdI angle and NCdN angle, respectively. Complex I is photoluminescent in the solid state at room temperature.  相似文献   

18.
The monomeric octa-aza bis-α-diimine macrocyclic complex [CoII(C10H20N8)(H2O)](ClO4)2 I, undergoes various reactions on the macrocyclic ligand. Reaction of complex I with triethylamine in double molar proportions, followed by slow aerial oxidation, produces a molecular dimeric complex [CoII(C10H14N8)]2, III, and a novel Co(I) complex [CoI(C10H19N8)], IV. Complex III is a staggered cofacial dimer with a cobalt-cobalt bond length 2.86(1) Å. The macrocyclic ligand of the complex contains an a-diimine function in each five-membered chelate ring, and a three-atom N-C-N? delocalized system in each six-membered chelate ring. Complex IV has the 5-5-6-6 chelate arrangement because one α-diimine moiety is rearranged to a syn-anti configuration. In the structure, the two fused six-membered chelate rings are fully conjugated and the two fused five-membered rings are saturated. However, when complex I reacts with excess triethylamine under the similar conditions, a dimeric complex of another type, [CoII(C10Hl6N8)]2, II, was generated, in which one N-N bond of the macrocyclic ligand is broken. Complex IV can be isolated also from the reaction of complex I with excess hydrazine, followed by slow aerial oxidation. When hydrazine in double molar proportions was used, complex [CoI(C10H17N8)(NHNH)] V, which contains a coordinated diazene ligand, was obtained. Only one six-membered chelate ring of complex V is deprotonated and oxidized to form a three-atom N-C-N? delocalized system. The structures of octa-aza complexes I-V are determined by X-ray crystallography: I, orthorhombic, C mca, a = 11.646(4), b = 17.049(3), c = 10.706(3) Å, Z = 4, R = 0.045, Rw = 0.047, based on 1024 reflections with I > 2σ(I); II, monoclinic, P 21/c, a = 9.814(3), b = 22.583(6). c = 14.632(9) Å, β = 98.90(5)°, Z = 4, R = 0.085, Rw = 0.101, based on 2033 reflections with I > 2σ(I); III, tetragonal, P 4/nmm, a = 15.614(3), c = 6.498(2) Å, Z = 4, R = 0.081, Rw = 0.115, based on 340 reflections with I > 2σ(I); IV, orthorhombic, P bca, a = 8.484(1), b = 16.662(3), c = 18.760(2) Å, Z = 8, R = 0.029, Rw = 0.024, based on 1441 reflections with I > 2σ(I); V, monoclinic, P 21/m, a = 7.892(3), b = 11.713(6), c = 9.326(4) Å, β = 108.03(3), Z = 2, R = 0.047, Rw = 0.056, based on 948 reflections with I > 2σ(I).  相似文献   

19.
The preparation and characterization of [CrnFe4-nO2(O2CMe)7(bipy)2]Cl (1, n=0; 2, n=2; 3, n=4, bipy=2,2'-bipyridine) are described. The three complexes (1, 2 and 3) are obtained by bipyridine-mediated conversion of trinuclear [CrnFe3-nO(O2CMe)6(H2O)3]+(1, n=0; 2, n=1; 3, n=3), and crystallized as three of approximate isomorphs. Crystal 2 is monoclinic with space group C2/c, a=27.454(5)Å, b=11.789(1)Å, c=16.570(3)Å, β=118.78(1)°, V=4700.8Å3, z=4, μ(MoK)=11.64cm?1, F(000)=2056, final R=0.058 and Rw=0.066 for 3479 reflections with I ? 3σ(I). The Fe and Cr atoms in the cation are all +3 oxide state and disordered in the lattice, which is also supported by its Mossbauer studies. The [Cr2Fe2O2]8+ core can be thought of as being derived from two edge-sharing M3O units (M=Fe or Cr), and as a butterfly-like structure. The cations' structure of all three crystals are similar to each other and have C2 symmetry. The species are characterized by IR spectra and magnetic techniques, with particular emphasis on differentiation of coordination bond strengths and electronic environment of metal atoms in these complexes.  相似文献   

20.
Rare Earth Halides Ln4X5Z. Part 1: C and/or C2 in Ln4X5Z The compounds Ln4X5Cn (Ln = La, Ce, Pr; X = Br, I and 1.0 < n < 2.0) are prepared by the reaction of LnX3, Ln metal and graphite in sealed Ta‐ampoules at temperatures 850 °C < T < 1050 °C. They crystallize in the monoclinic space group C2/m. La4I5C1.5: a = 19.849(4) Å, b = 4.1410(8) Å, c = 8.956(2) Å, β = 103.86(3)°, La4I5C2.0: a = 19.907(4) Å, b = 4.1482(8) Å, c = 8.963(2) Å, β = 104.36(3)°, Ce4Br5C1.0: a = 18.306(5) Å, b = 3.9735(6) Å, c = 8.378(2) Å, β=104.91(2)°, Ce4Br5C1.5: a = 18.996(2) Å, b = 3.9310(3) Å, c = 8.282(7) Å, β = 106.74(1)°, Pr4Br5C1.3: a = 18.467(2) Å, b = 3.911(1) Å, c = 8.258(7) Å, β = 105.25(1)° and Pr4Br5C1.5: a = 19.044(2) Å, b = 3.9368(1) Å, c = 8.254(7) Å, β = 106.48(1)°. In the crystal structure the lanthanide metals are connected to Ln6‐octahedra centered by carbon atoms or C2‐groups. The Ln6‐octahedra are condensed via opposite edges to chains and surrounded by X atoms which interconnect the chains. A part n of isolated C‐atoms is substituted by 1‐n C2‐groups. The C‐C distances range between 1.26 and 1.40Å. In the ionic formulation (Ln3+)4(X?)5(C4?)n(C2m?)1?n·e? with 0 < n < 1 and m = 2, 4, 6 (C22?, C24? C26?), there are 1 < e? < 5 electrons centered in metal‐metal bonds.  相似文献   

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