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1.
Gold disproportinates in the presence of the Zintl phases Ba3P2 or Ba3As2 forming BaAuP and BaAuAs, respectively, and BaAu2. The air and moisture sensitive ternary compounds crystallise in the ZrBeSi type of structure, an ordered variant of AlB2: BaAuP (P63/mmc; a = 440.68(6) pm; c = 899.8(2) pm; R1 = 0.0237; 183 independent reflections); BaAuAs (P63/mmc; a = 453.53(5) pm; c = 902.7(1) pm; R1 = 0.0255; 168 independent reflections). Both compounds, which are accessible as pure phases by reacting BaP or BaAs with gold, can be classified as poor metallic conductors. 相似文献
2.
Dodecahydro‐ closo ‐dodecaborates of the Heavy Alkaline‐Earth Metals from Aqueous Solution: Ca(H2O)7[B12H12] · H2O, Sr(H2O)8[B12H12], and Ba(H2O)6[B12H12] The crystalline hydrates of the heavy alkaline earth metal dodecahydro‐closo‐dodecaborates (M[B12H12] · n H2O, n = 6–8; M = Ca, Sr, Ba) are easily accessible by reaction of an aqueous (H3O)2[B12H12] solution with an alkaline earth metal carbonate (MCO3). By isothermic evaporation of the respective aqueous solution we obtained colourless single crystals which are characterized by X‐ray diffraction at room temperature. The three compounds Ca(H2O)7[B12H12] · H2O (orthorhombic, P212121; a = 1161.19(7), b = 1229.63(8), c = 1232.24(8) pm; Z = 4), Sr(H2O)8[B12H12] (trigonal, R3; a = 1012.71(6), c = 1462.94(9) pm; Z = 3) and Ba(H2O)6[B12H12] (orthorhombic, Cmcm; a = 1189.26(7) pm, b = 919.23(5) pm, c = 1403.54(9) pm; Z = 4) are neither formula‐equal nor isostructural. The structure of Sr(H2O)8[B12H12] is best described as a NaCl‐type arrangement, Ba(H2O)6[B12H12] rather forms a layer‐like and Ca(H2O)7[B12H12] · H2O a channel‐like structure. In first sphere the alkaline earth metal cations Ca2+ and Sr2+ are coordinated by just seven and eight oxygen atoms from the surrounding water molecules, respectively. A direct coordinative influence of the quasi‐icosahedral [B12H12]2– cluster anions becomes noticeable only for the Ba2+ cations (CN = 12) in Ba(H2O)6[B12H12]. The dehydratation of the alkaline earth metal dodecahydro‐closo‐dodecaborate hydrates has been shown to take place in several steps. Thermal treatment leads to the anhydrous compounds Ca[B12H12], Sr[B12H12] and Ba[B12H12] at 224, 164 and 116 °C, respectively. 相似文献
3.
ACu9X4 ‐ New Compounds with CeNi8, 5Si4, 5 Structure (A: Sr, Ba; X: Si, Ge) The new compounds SrCu9Si4 (a = 8.146(1), c = 11.629(2)Å), BaCu9Si4 (a = 8.198(2), c = 11.735(2)Å), SrCu9Ge4 (a = 8.273(2), c = 11.909(5)Å), and BaCu9Ge4 (a = 8.338(4), c = 12.011(7)Å) are formed by reaction of the elements at 1000° ‐ 1100 °C. They are isotypic (I4/mcm, Z = 4) and crystallize in an ordered variant of the cubic NaZn13 type structure, also built up by the binary phase BaCu13. In the ternary compounds the positions of Cu2 are orderly occupied by copper and silicon and germanium, respectively. This results in a lowering of symmetry and a distortion of the polyhedra. The metallic conductivity of the compounds was confirmed by measurements on BaCu9Si4. 相似文献
4.
Wan‐Feng Lin Qiu‐Ju Xing Jun Ma Jian‐Ping Zou Si‐Liang Lei Xu‐Biao Luo Guo‐Cong Guo 《无机化学与普通化学杂志》2013,639(1):31-34
The new spiroffite Mg2Te3O8 ( 1 ) was prepared by hydrothemal methods and structurally characterized by single‐crystal X‐ray diffraction analysis. Compound 1 crystallizes in the space group C2/c of the monoclinic system with two formula units in a cell: a = 12.6030(7), b = 5.2254(3), c = 11.6331(7) Å, β = 98.6960(10)°, V = 757.30(8) Å3. The structure features a 3D open‐framework with spiroffite topology that has large tunnels approximately 3.2 × 5.5 Å. The optical properties and thermal stability of 1 were characterized by UV and IR spectroscopy as well as TG. Calculations of the electronic band structure along with the density of states (DOS) indicate that the present compound is a semiconductor with an indirect band gap, and that the optical absorption is mainly originated from the charge transitions from O‐2p state to Te‐5p and Te‐5s states. 相似文献
5.
Sophia J. Makowski Evelyn Calta Michael Hörmannsdorfer Prof. Dr. Wolfgang Schnick 《无机化学与普通化学杂志》2012,638(2):345-351
The stability against hydrolysis of triazine tricarboxylate (TTC) in the presence of divalent transition metal and alkaline earth ions was investigated by means of X‐ray diffraction and FTIR spectroscopy. Depending on the size of the cation either formation of the respective triazine tricarboxylate salts or hydrolysis of TTC yielding oxalate was observed. The hydrolysis of TTC induced by transition metal ions could be explained in analogy to the hydrolysis of triazine tris(2‐pyrimidyl) as a result of ring tension caused by the coordination of these ions. By the reaction of potassium triazine tricarboxylate with alkaline earth salts in aqueous solution the alkaline earth triazine tricarboxylates M3[C3N3(CO2)3]2 · 12H2O (M = Sr, Ba) were obtained and analyzed by single‐crystal X‐ray diffraction. The isotypic salts represent the first examples of alkaline earth triazine tricarboxylates and the first TTC salts comprising solely divalent cations. 相似文献
6.
Enkhtsetseg Dashjav Guido Kreiner Frank R. Wagner Walter Schnelle Rüdiger Kniep Prof. Dr. 《无机化学与普通化学杂志》2007,633(9):1349-1358
Four new ternary carbometalates of the general formula RE2[Mo2C3] with RE = Ce, Sm, Tb and Dy have been prepared by a high temperature synthesis route. The Ce, Tb and Dy compounds crystallize isotypic to Er2[Mo2C3], Sm2[Mo2C3], however, is an isotype of Ho2[Cr2C3]. The crystal structures comprise polyanionic layers [(Mo2C3)6?] with the rare‐earth metal ions in between. The layers are constructed by edge and vertex connected MoC4 tetrahedra, which display strong covalent Mo–C bonds. The compounds show metallic behaviour close to the classical limit of 100 μΩ cm for metallic conductors. The magnetic properties are quite different, however they are consistent with the presence of trivalent RE3+ ions with the exception of Ce2[Mo2C3], which contains nonmagnetic Ce species. Electronic structure calculations reveal that the additional electron mainly populates the Ce partial structure. The title compounds extend the series of known carbomolybdates RE2[Mo2C3]. The late lanthanides Gd, Tb, Dy, Ho, Er, Tm, and Lu with comparatively small RE3+ ions and Ce as Ce4+ adopt the Er2[Mo2C3] structure type, whereas the early lanthanides Sm and Pr with larger RE3+ ions crystallize in the structure types of Ho2[Cr2C3] and Pr2[Mo2C3], respectively. 相似文献
7.
Synthesis and Crystal Structure of A Cu4As2 ( A : Ca–Ba, Eu) Steel‐gray single crystals of ACu4As2 with A = Ca–Ba and Eu respectively were synthesized by heating mixtures of the elements at about 900 °C. Structure determinations with X‐ray diffractometry data revealed, that the isotypic compounds crystallize in the rhombohedral CaCu4P2 type structure (R3m; Z = 3) (hexagonal axes see ”︁Inhaltsübersicht”︁”︁). Measurements of the susceptibility of EuCu4As2 showed divalent Eu and ferromagnetic order at 35 K. 相似文献
8.
Colorless single crystals of Cd2[μ8‐MTB] · 3H2O · DMF ( 1 ) were prepared in DMF/H2O solution [ 1 : space group C2/c (no. 15) with a = 1821.30(6), b = 2175.08(6), c = 1269.87(4) pm, β = 129.684(1)°]. The connection between the methane‐p‐benzoate tetraanions (MTB4–) and the Cd2+ cations leads to a three‐dimensional framework with channels extending along [1 10] and [110] with openings of 670 pm × 360 pm. The channel‐like voids accommodate water molecules and N,N‐dimethylformamide (DMF) molecules not bound to Cd2+. Colorless single crystals of [Cd4(2,2′‐bipy)4(μ7‐MTB)2] · 7DMF ( 2 ) were prepared in DMF in the presence of 2,2′‐bipyridine [ 2 : space group P1 (no. 2) with a = 1224.84(4), b = 1418.85(5), c = 2033.49(4) pm, α = 85.831(2)°, β = 88.351(2)°, γ = 68.261(1)°]. The coordination of MTB4– to Cd2+ results in infinite layers parallel to (001). The layers, not connected by any hydrogen bonds, contain small openings of about 320 pm × 340 pm. 相似文献
9.
Systematic studies on thio‐ and selenoborates containing heavier metal cations led to the new crystalline phase EuB2S4. The crystal structure of the europium metathioborate reveals polymeric [(B2S4)2—]n anions and divalent Eu‐cations which are connected via ionic interactions. The building blocks of the anions consist of BS4‐tetrahedra. Condensation of these BS4‐tetrahedra leads to corner‐ and edge‐sharing 2D‐networks running parallel to (1 0 0). Evacuated carbon coated silica tubes were used as reaction vessels since temperatures up to 990 K were applied. EuB2S4 crystallizes in the monoclinic space group P21/c (no. 14) with a = 6.4331(6)Å, b = 14.099(1)Å, c = 6.0731(6)Å, β = 110.55(8)° and Z = 4. 相似文献
10.
To explore the coordination possibilities of fluorene‐based ligands, two manganese(II) complexes with the ligand 9,9‐dibutyl‐9H‐fluorene‐2,7‐carboxylate ( L ) were synthesized and characterized: [Mn2( L )2(DMF)3]∞ ( 1 ) and [Mn2( L )2(DMF)]∞ ( 2 ). X‐ray single‐crystal diffraction analyses show that complex 1 has a two‐dimensional (2D) (4,4) structure, whereas complex 2 consits of a three‐dimensional (3D) (4,5)‐connected topology framework. The results indicate that the steric bulk of the fluorene ring in H2 L plays an important role in the formations of 1 and 2 . Additional pyridine‐based ligands govern the formation of the final frameworks of 2 . Moreover, the luminescent properties of these complexes were briefly investigated. 相似文献
11.
《Journal of Coordination Chemistry》2012,65(24):4244-4253
A new 3-D wheel-like calcium–cobalt phosphotungstate, Na6Ca3[Ca2(H2O)6Co9(OH)3(H2O)6(HPO4)2(PW9O34)3], is reported and characterized by IR, UV, and single-crystal X-ray diffraction. The crystal structure consists of an infinite 3-D array of [Ca2(H2O)6Co9(OH)3(H2O)6(HPO4)2(PW9O34)3]12? anions (1) connected by sodium and calcium metal cations. The novel feature is the presence of two Ca2+, bonded to oxygen of HPO4? and to H2O spanning opposite sides in the complex anion. The stability of the crystalline product and its morphology were studied by SEM-EDX and DSC techniques. 相似文献
12.
《先进技术聚合物》2018,29(2):867-873
The push to advance efficient, renewable, and clean energy sources has brought with it an effort to generate materials that are capable of storing hydrogen. Metal–organic framework materials (MOFs) have been the focus of many such studies as they are categorized for their large internal surface areas. We have addressed one of the major shortcomings of MOFs (their processibility) by creating and 3D printing a composite of acrylonitrile butadiene styrene (ABS) and MOF‐5, a prototypical MOF, which is often used to benchmark H2 uptake capacity of other MOFs. The ABS‐MOF‐5 composites can be printed at MOF‐5 compositions of 10% and below. Other physical and mechanical properties of the polymer (glass transition temperature, stress and strain at the breaking point, and Young's modulus) either remain unchanged or show some degree of hardening due to the interaction between the polymer and the MOF. We do observe some MOF‐5 degradation through the blending process, likely due to the ambient humidity through the purification and solvent casting steps. Even with this degradation, the MOF still retains some of its ability to uptake H2, seen in the ability of the composite to uptake more H2 than the pure polymer. The experiments and results described here represent a significant first step toward 3D printing MOF‐5‐based materials for H2 storage. 相似文献
13.
Three two‐dimensional (2D) coordination complexes, namely [Ca2(HL)2(H2O)5]n · 2nH2O ( 1 ), [Sr(HL)(H2O)3]n · nH2O ( 2 ), and [Ba(HL)(H2O)3]n · nH2O ( 3 ) [H3L = 3‐(3‐carboxy‐phenoxy) phthalic acid], were synthesized by using the ligand H3L and alkaline earth metals. Structural analysis reveals that the structures of complexes 1 – 3 can be described as 2D networks with the point (Schälfli) symbol for net: {312 · 414 · 52} topology. Additionally, the thermal stability and solid‐state luminescent properties of compounds 1 – 3 were investigated at room temperature. The quantum yield (QY) of compound 2 is 10.75 %, which is much higher than the QY of the free H3L ligand (QYH3L < 1 %). 相似文献
14.
LaPt2Ge2 and EuPt2Ge2 – Revision of the Crystal Structures LaPt2Ge2 was rechecked by single crystal X‐ray methods resulting in space group P21/c (in place of P21) and the lattice constants a = 9.953(3), b = 4.439(1), c = 8.879Å, β = 90.62(4)°, and Z = 4. In contrast to previous reports the cell volume had to be doubled. The same is true for EuPt2Ge2 (a = 9.731(1), b = 4.446(1), c = 8.823(1) Å, β = 91.26(1)°). The crystal structures correspond to a monoclinic variant of the tetragonal CaBe2Ge2 type, whereas the distortion can be described as different rotations of the coordination polyhedra around the La and Eu atoms, respectively. It is most likely that the compounds APt2Ge2 with A = Ca, Y, La‐Dy undergo phase transitions at higher temperatures forming then the undistorted CaBe2Ge2 type, space group P4/nmm. This was confirmed for SmPt2Ge2 (a = 4.292(1), c = 9.980(1) Å; Z = 2) and might also be the case for APt2Ge2 with A = Ca, Nd, Sm, Eu, and Gd. 相似文献
15.
BaClSCN and Na4Mg(SCN)6: Two New Thiocyanates of the Alkaline Earth Metals The reaction of BaCl2 and NaSCN yielded single crystals of BaClSCN (P 21/m, Z = 2, a = 588.6(1) pm, b = 465.8(1) pm, c = 864.4(2) pm, β = 100.20(3)°, Rall = 0.0214). According to X‐ray single crystal investigations, the structure consists of anionic SCN– and Cl– layers, respectively, alternating in [001] direction. The SCN–‐ions are connected via the N and the S atoms to the cations. Na4Mg(SCN)6 (P 3 1c, Z = 2, a = 863.8(1) pm, c = 1399.3(2) pm, Rall = 0.0870), which was obtained from a melt of NaSCN and MgCl2, consists of anionic layers with the cations between the sheets. The holes are filled altenatingly by Na+ or Na+ and Mg2+. Regarding only the C‐atoms of the SCN– group, the structure can be described as a hexagonal closest packing whith the cations occupying 5/6 of the octahedral voids. 相似文献
16.
Hubert Schmidbaur Hans Georg Classen Joachim Helbig 《Angewandte Chemie (International ed. in English)》1990,29(10):1090-1103
Magnesium and other alkaline-earth and alkali metals play an important role in the biochemistry of virtually all living organisms. In contrast to “trace elements” these “common metals” are distributed in most cells and tissues, often in considerable concentrations, and a constant supply is indispensable for unrestricted performance of biological functions. In contemporary medicine, various forms of magnesium therapy are recommended in order to compensate for magnesium deficiency due to certain dysfunctions as well as to loss from excessive transpiration. In addition, there are numerous indications for prophylaxis. Magnesium is usually administered orally in the form of “complexes” with “natural” anions derived from I -aspartic, L -glutamic, L -pyroglutamic (pidolic), citric, and orotic acid. Analytical, electrochemical, and spectroscopic investigations of aqueous solutions of these Pharmaceuticals, together with X-ray diffraction studies of crystalline samples, have given a detailed knowledge of these coordination compounds. Only certain combinations can be addressed as magnesium complexes, whereas others are only present as aquo complexes both in aqueous solutions and in the solid state. Thus, a delicate balance of metal complexation and hydrogen bonding exists for the components of the drugs, which is relevant for the metal carrier functions of the organic ligands. Compared with the more flexible stereochemistry of Ca, Sr, Ba, MnII , Zn, Li, Na, and K complexes, which have coordination numbers between 4 and 9, octahedral hexacoordination is found exclusively for magnesium, the most stereoselective of these metals. 相似文献
17.
Jun-Ling Song 《Journal of solid state chemistry》2004,177(7):2557-2564
Hydrothermal reactions of lead(II) acetate with 5-sulfoisophthalic acid monosodium salt (NaH2BTS) and N-(phosphonomethyl)-N-methylglycine, MeN(CH2CO2H)(CH2PO3H2) (H3L1), or a new aminodiphosphonic acid, 3-Pyridyl-CH2N(CH2PO3H2)2 (H4L2), afforded two novel lead(II) phosphonate-sulfonate hybrids, namely, Pb3[L1][BTS][H2O]·H2O 1 and Pb2[HL3][BTS]·H2O 2 (H2L3=3-Pyridyl-CH2(Me)N(CH2PO3H2)). H2L3 was formed as a result of the decomposition of one phosphonate group in H4L2 during the reaction. Compound 1 crystallizes in the triclinic space group with a=9.9148(4) Å, b=10.4382(4) Å, c=10.6926(2) Å, α=96.495(2)°, β=110.599(2)°, γ=98.433(2)°, V=1008.31(6) Å3, and Z=2. The structure of compound 1 features a 3D network built from the interconnection of hexanuclear Pb6(L1)2 units and 1D double chains of lead(II) carboxylate-sulfonate. Compound 2 crystallizes in the monoclinic space group P21/c with a=9.5403(7) Å, b=11.6170(8) Å, c=19.7351(15) Å, β=97.918(2)°, V=2166.4(3) Å3, and Z=4. Compound 2 has a 3D network structure built by the cross-linkage of 1D double chains of lead(II) phosphonates and 2D layers of lead(II) carboxylate-sulfonate. 相似文献
18.
A Novel Three‐Dimensional Copper(II) 1,2‐Ethylenediphosphonate Framework with Channel‐like Voids
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Turquoise monoclinic single crystals of the novel three‐dimensional Cu2[μ8‐O3P(CH2)2PO3] · 3.2H2O coordination polymer were prepared using the silica gel method. Space group C2/m (no. 12) with a = 1483.6(2), b = 668.44(8), c = 436.30(6) pm, β = 93.28(2)°. The Cu2+ cation is coordinated by four oxygen atoms stemming from the 1,2‐ethylenediphosphonate dianions in a square planar manner and two water molecules in the axial positions. The connection between the Cu2+ cations and the [CPO3] units from the 1,2‐ethylenediphosphonate dianions leads to layers parallel to (100), which are linked by the ethylene groups to a three‐dimensional framework with channel‐like voids. The channel‐like voids accommodate water molecules not bound to Cu2+ and extend parallel to [001] with an opening of about 550 pm × 260 pm. Magnetic measurements reveal an antiferromagnetic behavior due to a superexchange coupling between Cu2+ ions through an oxygen bridge. The UV/Vis spectrum reveals three d–d transition bands at 694, 774, and 918 nm. The compound can be fully dehydrated by thermal treatment and rehydrated by storage in ambient air. 相似文献
19.
Triclinic single crystals of Cu4(H3N–(CH2)9–NH3)(OH)2[C6H2(COO)4]2 · 5H2O were prepared in aqueous solution at 80 °C in the presence of 1,9‐diaminononane. Space group P$\bar{1}$ (no. 2) with a = 1057.5(2), b = 1166.0(2), c = 1576.7(2) pm, α = 106.080(10)°, β = 90.73(2)° and γ = 94.050(10)°. The four crystallographic independent Cu2+ ions are surrounded by five oxygen atoms each with Cu–O distances between 191.4(3) and 231.7(4) pm. The connection between the Cu2+ coordination polyhedra and the [C6H2(COO)4]4– anions yields three‐dimensional framework with negative excess charge and wide centrosymmetric channel‐like voids. These voids extend parallel to [001] with the diagonal of the nearly rectangular cross‐section of approximately 900 pm. The channels of the framework accommodate [H3N–(CH2)9–NH3]2+ cations and water molecules, which are not connected to Cu2+. The nonane‐1,9‐diammonium cations adopt a partial gauche conformation. Thermoanalytical measurements in air show a loss of water of crystallization starting at 90 °C and finishing at approx. 170 °C. The dehydrated compound is stable up to 260 °C followed by an exothermic decomposition yielding copper oxide. 相似文献
20.
Two new 3D heterometallic frameworks, [Me2NH2][CaCd2(BTC)(HBTC)2] · 4H2O ( 1 ) and [Ba11Co2(BTC)8(μ3‐OH)2(μ2‐H2O)6(H2O)16] ( 2 ) (H3BTC = 1,3,5‐benzenetricarboxylic acid, Me2NH2 = protonated dimethylamine), were synthesized using solvothermal and hydrothermal techniques, respectively. Complex 1 features a 3D microporous framework; it contains hourglass‐like trinuclear [CaCd2(COO)6] clusters that are bridged by –COO– groups and form zigzag chains. These chains are further interlinked by the –COO– groups of BTC3– ligands into 2D layers with interesting flower‐like configuration, which, in turn, are connected by HBTC2– ligands to afford the 3D structure. Me2NH2+ cations not only balance the negative charges of the host framework but also play template roles to fill in the channels, further consolidating the whole framework. The complicated 3D network of complex 2 is constructed by the interconnection of 2D layers, which, in turn, are made of the infinite inorganic chains based on hexanuclear [Ba6] clusters, and these 1D chains are decorated by {CoO6} octahedrons. Interestingly, the 2D layer can be viewed as a unique structure composed of two different kinds of heart‐shaped rings, which partially overlapped in apical positions to produce a ten‐membered ring window. Moreover, the luminescence properties of 1 – 2 and the gas adsorption property of 1 have also been studied. 相似文献