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1.
Syntheses, Crystal Structure, and Properties of the Cage‐like, Hexaacidic P12S12N8(NH)6 · 14 H2O and its Salts Li6[P12S12N14] · 26 H2O, (NH4)6[P12S12N14] · 10 H2O, and K6[P12S12N14] · 8 H2O The cage‐like acid P12S12N8(NH)6 · 14 H2O was obtained by the reaction of KSCN with P4S10 via the formation of K6[P12S12N14] · 8 H2O and subsequent ion exchange reactions in aqueous solution. Starting from the acid the salts Li6[P12S12N14] · 26 H2O and (NH4)6[P12S12N14] · 10 H2O were synthesized. According to X‐ray single‐crystal structure analyses the compounds are built up by isosteric P–N cages [P12S12N[3]8N[2]6]6–. Each of them is made up of twelve P3N3 rings, which exclusively exhibit the boat conformation. The cages have the idealized symmetry 2/m3; P12S12N8(NH)6 · 14 H2O: P1, a = 1119.11(7), b = 1123.61(7), c = 1125.80(6) pm, α = 80.186(4), β = 60.391(4), γ = 60.605(4)°, Z = 1; Li6[P12S12N14] · 26 H2O: Fm3, a = 1797.4(1) pm, Z = 4; (NH4)6[P12S12N14] · 10 H2O: P63, a = 1153.2(1), c = 2035.6(2) pm, Z = 2; K6[P12S12N14] · 8 H2O: R3c, a = 1142.37(5), c = 6009.6(3) pm, Z = 6. In the crystal the cages of the acid are crosslinked via hydrate molecules by hydrogen bonds. The cations in the salts show a high‐mobility and are located between the cages.  相似文献   

2.
Concentrated aqueous solutions of magnesium chloride and calcium nitrate, respectively, allow on addition of the potassium salt of tetrathiosquarate, K2C4S4 · H2O, the isolation of the earth alkaline salts MgC4S4 · 6 H2O ( 1 ) and CaC4S4 · 4 H2O ( 2 ) as orange and red crystals. The crystal structure determinations ( 1 : monoclinic, C2/c, a = 17.2280(7), b = 5.9185(2), c = 13.1480(4) Å, β = 104.730(3)°, Z = 4; 2 : monoclinic, P21/m, a = 7.8515(3), b = 12.7705(5), c = 10.6010(4) Å, β = 93.228(2)°, Z = 4) show the presence of C4S42? ions with almost undistorted D4h symmetry having average C–C and C–S bond lengths of 1.451Å and 1.659Å for 1 and 1.451Å and 1.655Å for 2 . The structure of 1 contains discrete, octahedral [Mg(H2O)6]2+ complexes. Several O–H····O and O–H····S bridges with H····O and H····S distances of less than 2.50Å connect cations and anions. The structure of 2 is built of concatenated, edge‐sharing Ca(H2O)6S2 polyhedra. The Ca2+ ions have the coordination number eight, C4S42? act as a chelating ligands towards Ca2+ with Ca–S distances of 3.14Å. The infrared and Raman spectra show bands typical for the molecular building units of the two compounds.  相似文献   

3.
Diammonium tricyanomelaminate dihydrate [NH4]2[C6N9H] · 2 H2O ( 1 ) and dimelaminium tricyanomelaminate melamine dihydrate [C3N6H7]2[C6N9H] · C3N6H6 · 2 H2O ( 2 ) were obtained by metathesis reactions from Na3[C6N9] in aqueous solution and characterized by single‐crystal X‐ray diffraction and 15N solid‐state NMR spectroscopy ( 1 ). Both salts contain mono‐protonated tricyanomelaminate (TCM) anions and crystallize as dihydrates. Considering charge balance requirements, the crystal structure of 1 (C2/c, a = 3181.8(6) pm, b = 360.01(7) pm, c = 2190.4(4) pm, β = 112.39(3)°, V = 2319.9(8) 106 · pm3) can best be described by assuming a random distribution of an ammonium ion – crystal water pair over two energetically similar sites. Apart from two melaminium cations, 2 (P21/c, a = 674.7(5) pm, b = 1123.6(5) pm, c = 3400.2(5) pm, β = 95.398(5), V = 2566(2) 106 · pm3) contains one neutral melamine per formula unit acting as an additional “solvent” molecule and yielding a donor‐acceptor type of π–stacking interaction.  相似文献   

4.
Single crystals of [Cr(H2O)6]2[B12H12]3 · 15H2O and [In(H2O)6]2[B12H12]3 · 15H2O were obtained by reactions of aqueous solutions of the acid (H3O)2[B12H12] with chromium(III) hydroxide and indium metal shot, respectively. The title compounds crystallize isotypically in the trigonal system with space group R$\bar{3}$ c (a = 1157.62(3), c = 6730.48(9) pm for the chromium, a = 1171.71(3), c = 6740.04(9) pm for the indium compound, Z = 6). The arrangement of the quasi‐icosahedral [B12H12]2– dianions can be considered as stacking of two times nine layers with the sequence …ABCCABBCA… and the metal trications arrange in a cubic closest packed …abc… stacking sequence. The metal trications are octahedrally coordinated by six water molecules of hydration, while another fifteen H2O molecules fill up the structures as zeolitic crystal water or second‐sphere hydrating species. Between these free and the metal‐bonded water molecules, bridging hydrogen bonds are found. Furthermore, there is also evidence of hydrogen bonding between the anionic [B12H12]2– clusters and the free zeolitic water molecules according to B–Hδ ··· δ+H–O interactions. Vibrational spectroscopy studies prove the presence of these hydrogen bonds and also show slight distortions of the dodecahydro‐closo‐dodecaborate anions from their ideal icosahedral symmetry (Ih). Thermal decomposition studies for the example of [Cr(H2O)6]2[B12H12]3 · 15H2O gave no hints for just a simple multi‐stepwise dehydration process.  相似文献   

5.
Preparation and Crystal Structures of the first Alkalimetall‐hexacarbonato‐oxotetraberyllates: K6[Be4O(CO3)6] · 7 H2O and K6[Be4O(CO3)6] K6[Be4O(CO3)6] · 7 H2O has been prepared by dissolving freshly precipitated Be(OH)2 in an aqueous KHCO3 solution. After enriching the title compound by extraction with ethanol the heptahydrate crystallizes from the organic phase (triklin, P1¯ (No. 2) with a = 951, 01(11), b = 958, 45(12), c = 1601, 7(2) pm, α = 79, 253(13)°, β = 78, 943(12)°, γ = 65, 119(12)°, VEZ = 1290, 6(3)·106 pm3, Z = 2). Thermal decomposition forms rhombohedral crystals of the anhydrous compound (trigonal‐rhombohedric, R3¯ (No. 148) with a = 1416, 42(6), c = 1704, 5(1) pm, VEZ = 2961, 4(3)·106 pm3, Z = 6).  相似文献   

6.
Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl, Br, NO3) cocrystallize in aqueous solutions of [Ta6Br12]2+ in the presence of Cu2+ ions. The crystal structures of [Ta6Br12(H2O)6]Cl2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 1 ) and [Ta6Br12(H2O)6]Br2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta6Br12]2+ in the [Ta6Br12(H2O)6]2+ cation and [Ta6Br12]4+ in trans‐[Ta6Br12(OH)4(H2O)2]. Average bond distances in the [Ta6Br12(H2O)6]2+ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Bri , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Bri , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta6‐Br12(OH)4(H2O)2]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Bri, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H2O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Bri, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H2O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta6Cl12]2+ oxidized to [Ta6Cl12]4+ , whereas [Nb6X12]2+ clusters were not affected by the Cu2+ ion.  相似文献   

7.
On the Crystal Structures of the Transition‐Metal(II) Dodecahydro‐closo‐Dodecaborate Hydrates Cu(H2O)5.5[B12H12]·2.5 H2O and Zn(H2O)6[B12H12]·6 H2O By neutralization of an aqueous solution of the free acid (H3O)2[B12H12] with basic copper(II) carbonate or zinc carbonate, blue lath‐shaped single crystals of the octahydrate Cu[B12H12]·8 H2O (≡ Cu(H2O)5.5[B12H12]·2.5 H2O) and colourless face‐rich single crystals of the dodecahydrate Zn[B12H12]·12 H2O (≡ Zn(H2O)6[B12H12]·6 H2O) could be isolated after isothermic evaporation. Copper(II) dodecahydro‐closo‐dodecaborate octahydrate crystallizes at room temperature in the monoclinic system with the non‐centrosymmetric space group Pm (Cu(H2O)5.5[B12H12]·2.5 H2O: a = 768.23(5), b = 1434.48(9), c = 777.31(5) pm, β = 90.894(6)°; Z = 2), whereas zinc dodecahydro‐closo‐dodecaborate dodecahydrate crystallizes cubic in the likewise non‐centrosymmetric space group F23 (Zn(H2O)6[B12H12]·6 H2O: a = 1637.43(9) pm; Z = 8). The crystal structure of Cu(H2O)5.5[B12H12]·2.5 H2O can be described as a monoclinic distortion variant of the CsCl‐type arrangement. As characteristic feature the formation of isolated [Cu2(H2O)11]4+ units as a condensate of two corner‐linked Jahn‐Teller distorted [Cu(H2O)6]2+ octahedra via an oxygen atom of crystal water can be considered. Since “zeolitic” water of hydratation is also present, obviously both classical H–Oδ?···H–O and non‐classical B–Hδ?···H–O hydrogen bonds play a significant role for the stabilization of the structure. A direct coordinative influence of the quasi‐icosahedral [B12H12]2? anions on the Cu2+ cations has not been determined. The zinc compound Zn(H2O)6[B12H12]·6 H2O crystallizes in a NaTl‐type related structure. Two crystallographically different [Zn(H2O)6]2+ octahedra are present, which only differ in their relative orientation within the packing of the [B12H12]2? anions. The stabilization of the crystal structure takes place mainly via H–Oδ?···H–O hydrogen bonds, since again the hydrogen atoms of the [B12H12]2? anions have no direct coordinative influence on the Zn2+ cations.  相似文献   

8.
The reaction of the nitrates M(NO3)3·6H2O (M = La, Pr) and (H3O)2PtCl6 led to yellow single crystals of [M(NO3)2(H2O)6]2[PtCl6]·2H2O (M = La, Pr) (monoclinic, P21/c, Z = 2, La/Pr: a = 697.4(3)/695.5(1), b = 1654.5(1)/1652.5(2), c = 1317.7(6)/1318.5(3) pm, β = 93.97°(7)/93.93°(2), Rall = 0.0169/0.0659) while the reaction of M(NO3)3·5H2O (M = Gd, Dy) and (H3O)2PtCl6 yielded yellow single crystals of [M(NO3)(H2O)7][PtCl6]·4H2O (monoclinic, P21/n, Z = 4, Gd/Dy: a = 838.72(3)/838.40(2), b = 2131.98(6)/2139.50(7), c = 1142.63(3)/1143.10(3) pm, β = 95.670(4)/95.698(3), Rall = 0.0475/0.0337). The crystal structures consist of octahedral [PtCl6]2? anions and complex [M(NO3)2(H2O)6]2+ and [M(NO3)(H2O)7]2+ cations, respectively. The thermal decomposition of both types of compounds leads via various steps to elemental platinum and the oxide chlorides MOCl (M = La, Pr, Gd, Dy).  相似文献   

9.
Alkaline Molybdotellurates: Preparation and Crystal Structures of Rb6[TeMo6O24] · 10H2O and Rb6[TeMo6O24] · Te(OH)6 · 6H2O Single crystals of Rb6[TeMo6O24] · 10 H2O and Rb6[TeMo6O24] · Te(OH)6 · 6 H2O, respectively, were grown from aqueous solution. Rb6[TeMo6O24] · 10 H2O possesses the space group P1 . The lattice dimensions are a = 963.40(13), b = 972.56(12), c = 1 056.18(13) pm, α = 97.556(10), β = 113.445(9), γ = 102.075(10)°; Z = 1, 2 860 reflections, 215 parameters refined, Rg = 0.0257. The centrosymmetrical [TeMo6O24]6? anions are stacked parallel to [010]. Rb(2) is coordinated with one exception by water molecules only. Folded chains consisting of [TeMo6O24]6? anions and Rb(2) coordination polyhedra which are linked to pairs represent the prominent structural feature. Rb6[TeMo6O24] · Te(OH)6 · 6 H2O crystallizes monoclinically in the space group C2/c with a = 1 886.4(3), b = 1 000.9(1), c = 2 126.5(3) pm, and β = 115.90(1)°; Z = 4, 3 206 reflections, 240 parameters refined, Rg = 0.0333. It is isostructural in high extent with (NH4)6[TeMo6O24] · Te(OH)6 · 7 H2O. Hydrogen bonds between Te(OH)6 molecules and [TeMo6O24]6? anions establish infinite strands. The [TeMo6O24]6? anions gather around Te(OH)6 providing channel-like voids extending parallel to [001].  相似文献   

10.
K2[CrF5·H2O] is monoclinic: a = 9.6835(3) Å, b = 7.7359(2) Å, c = 7.9564(3) Å, β = 95.94(1)°, Z = 4, space group C2/c (no 15). Its crystal structure was solved from its X‐ray powder pattern recorded on a powder diffractometer, using for the refinement the Rietveld method. It is built up from isolated octahedral [CrF5·OH2]2? anions separated by potassium cations. The dehydration of K2[CrF5·H2O] leads to anhydrous orthorhombic K2CrF5: a = 7.334(2) Å, b = 12.804(4) Å, c = 20.151(5) Å, Z = 16, space group Pbcn (no 60), isostructural with K2FeF5.  相似文献   

11.
Synthesis, Crystal Structure, and Thermal Decomposition of Mg(H2O)6[B12H12] · 6 H2O By reaction of an aqueous solution of the free acid (H3O)2[B12H12] with MgCO3 and subsequent isothermic evaporation of the resulting solution to dryness, colourless, bead‐shaped single crystals of the dodecahydrate of magnesium dodecahydro closo‐dodecaborate Mg(H2O)6[B12H12] · 6 H2O (cubic, F4132; a = 1643.21(9) pm, Z = 8) emerge. The crystal structure is best described as a NaTl‐type arrangement in which the centers of gravity of the quasi‐icosahedral [B12H12]2— anions (d(B—B) = 178—180 pm, d(B—H) = 109 pm) occupy the positions of Tl while the Mg2+ cations occupy the Na+ positions. A direct coordinative influence of the [B12H12]2— units at the Mg2+ cations is however not noticeable. The latter are octahedrally coordinated by six water molecules forming isolated hexaaqua complex cations [Mg(H2O)6]2+ (d(Mg—O) = 206 pm, 6×). In addition, six “zeolitic” water molecules are located in the crystal structure for the formation of a strong O—Hδ+···δ—O‐hydrogen bridge‐bonding system. The evidence of weak B—Hδ—···δ+H—O‐hydrogen bonds between water molecules and anionic [B12H12]2— clusters is also considered. Investigations on the dodecahydrate Mg[B12H12] · 12 H2O (≡ Mg(H2O)6[B12H12] · 6 H2O) by DTA/TG measurements showed that its dehydration takes place in two steps within a temperature range of 71 and 76 °C as well as at 202 °C, respectively. Thermal treatment eventually leads to the anhydrous magnesium dodecahydro closo‐dodecaborate Mg[B12H12].  相似文献   

12.
Rubidium dihydrogentricyanomelaminate semihydrate Rb[H2C6N9] · 1/2 H2O was obtained as colorless rod‐like single crystals from a solution of Rb3[C6N9] · H2O and 0.1 M HCl after water evaporation at room temperature. According to the X‐ray single‐crystal structure determination (Rb[H2C6N9] · 1/2 H2O: C2/c (no. 15), a = 2007.4(3) pm, b = 512.2(1) pm, c = 2168.0(4) pm, β = 111.66(2)°, Z = 8, R1 = 0.059, 2391 independent reflections, 159 parameters) Rb+ and cyclic planar [H2C6N9] ions as well as hydrate water molecules occur in the crystal. Rb[H2C6N9] · 1/2 H2O was investigated by FTIR and Raman spectroscopy, TG measurements and temperature‐dependent X‐ray powder diffraction. According to the thermoanalytic investigations, dehydration of Rb[H2C6N9] · 1/2 H2O starts above 60 °C and is finished below 250 °C.  相似文献   

13.
The transition metal dihydrogen hypodiphosphate hydrates K2[Co(H2P2O6)2(H2O)2] · H2O ( 1 ), K2[Ni(H2P2O6)2(H2O)2] · H2O ( 2 ), K2[Cu(H2P2O6)2(H2O)2] · H2O ( 3 ) and K2[Zn(H2P2O6)2(H2O)2] · H2O ( 4 ) were synthesized and characterized by single crystal structure determination. The compounds 1 – 4 crystallize isotypic in the monoclinic space group C2/m (no. 12) with two formula units in the unit cell. The crystal structure is built up by [H2P2O6]2– units in an eclipsed conformation, by the corresponding transition metal, potassium cations, and water molecules. The eclipsed conformation of the [H2P2O6]2– has not been previously observed in none of known hypodiphosphates(IV) analyzed via X‐ray diffraction. However, its proposed based on spectroscopic methods. FT‐IR/FIR and FT‐Raman spectra of the crystalline salts were recorded and the thermal behavior of the compounds was investigated.  相似文献   

14.
Colourless block‐shaped crystals of [(NH4)2(2.2.2‐cryptand)2][P2S8] ( 1 ) and [(NH4)2(18‐crown‐6)2][P2S8]·H2O ( 2 ) could be obtained by the reaction of an aqueous solution of ammonium hexathiohypodiphosphate, (NH4)4P2S6·2 H2O, with sulfur and 2.2.2‐cryptand or 18‐crown‐6. The crystal structures of both compounds have been determined by single‐crystal X‐Ray diffraction analysis. Compound 1 crystallizes in the monoclinic space group C2/c with a = 2032.7(2), b = 1243.6(2), c = 2244.6(2) pm, β = 98.64(1)°, and Z = 8, whereas compound 2 crystallizes also monoclinic in the space group P21/c with a = 2121.3(2), b = 865.5(1), c = 2345.4(2) pm, β = 91.96(1)°, and Z = 4. It could be established that the title compounds contain a new type of six‐membered [1,2‐P2S4] ring with P – P bond and three S – S linkages. The tetrahedral environment of each phosphorus is completed by a (formally) single and double bonded sulfur atom attached externally to the [1,2‐P2S4] ring. These terminal PS2 units are mesomerically stabilized according to their P – S distances. FT‐IR and FT‐Raman spectra of the title compounds are recorded and interpreted.  相似文献   

15.
Concentrated aqueous solutions of strontium chloride and barium chloride, respectively, allow on addition of the potassium salt of tetrathiosquarate, K2C4S4·H2O, the isolation of the earth alkaline salts SrC4S4·4 H2O ( 1 ) and Ba4K2(C4S4)5·16 H2O ( 2 ), both as dark red crystals. The crystal structure determinations ( 1 : orthorhombic, Pnma, a = 8.149(1), b = 12.907(2), c = 10.790(2) Å, Z = 4; 2 : orthorhombic, Pbca, a = 15.875(3), b = 21.325(5), c = 16.119(1) Å, Z = 4) show the presence of C4S42− ions with only slightly distorted D4h symmetry having average C–C and C–S bond lengths of 1.41Å and 1.681Å for 1 and 1.450Å and 1.657Å for 2 . The structure of 1 contains concatenated edge‐sharing Sr(H2O)6S2 polyhedra. The Sr2+ ions are in eight‐fold coordination with Sr–O distances of 2.50–2.72Å and Sr–S distances of 3.21Å, (C4S4)2− acts as a chelating ligand towards Sr2+. The structure is closely related to the previously reported Ca2+ containing analogue, which is of lower symmetry belonging to the monoclinic crystal system. A supergroup‐subgroup relation between the space groups of both structures is present. The structure of 2 is made up of Ba2+ and K+ ions in eight and nine‐fold coordination by H2O molecules and (C4S4)2− ions which act as chelating ligands towards one cation and bridging between two cations. The coordination polyhedra of the cations are connected by common edges and corners in two dimensions to layers which are connected by tetrathiosquarate ions to a three‐dimensional network. The infrared and Raman spectra show bands typical for the molecular building units of the two compounds.  相似文献   

16.
Hydrothermal investigations in the system MgO/B2O3/P2O5(/H2O) yielded two new magnesium borophosphates, Mg2(H2O)[BP3O9(OH)4] and Mg(H2O)2[B2P2O8(OH)2]·H2O. The crystal structures were solved by means of single crystal X‐ray diffraction. While the acentric crystal structure of Mg2(H2O)[BP3O9(OH)4] (orthorhombic, P212121 (No. 19), a = 709.44(5) pm, b = 859.70(4) pm, c = 1635.1(1) pm, V = 997.3(3) × 106 pm3, Z = 4) contains 1D infinite chains of magnesium coordination octahedra interconnected by a borophosphate tetramer, Mg(H2O)2[B2P2O8(OH)2]·H2O (monoclinic, P21/c (No. 14), a = 776.04(5) pm, b = 1464.26(9) pm, c = 824.10(4) pm, β = 90.25(1)°, V = 936.44(9) × 106 pm3,Z = 4) represents the first layered borophosphate with 63 net topology. The structures are discussed and classified in terms of structural systematics.  相似文献   

17.
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   

18.
Two supramolecular architectures, [Mn(3‐bpd)2(NCS)2(H2O)2]·2H2O ( 1 ) and {[Mn(bpe)(NCS)2(H2O)2]·(3‐bpd)·(bpe)·H2O}n ( 2 ) [bpe = 1,2‐bis(4‐pyridyl)ethylene and 3‐bpd = 1,4‐bis(3‐pyridyl)‐2,3‐diaza‐1,3‐butadiene] have been synthesized and characterized by spectroscopic, elemental and single crystal X‐ray diffraction analyses. Compound 1 crystallizes in the monoclinic system, space group P21/c, with chemical formula C26H28Mn N10O4S2, a = 9.1360(6), b = 9.7490(6), c = 17.776(1) Å, β = 93.212(1)°, and Z = 2 while compound 2 crystallizes in the orthorhombic system, space group P212121, with chemical formula C38H36Mn1N10O3S2, a = 14.1902(6), b = 15.4569(7), c = 18.2838(8) Å, α = β = γ = 90°, and Z = 4. Structural determination reveals that the coordination geometry at Mn(II) in compound 1 or 2 is a distorted octahedral which consists of two nitrogen donors of two NCS?ligands, two oxygen donors of two water molecules, and two nitrogen donors of two 3‐bpd ligands for 1 and two dpe ligands for 2 , respectively. The two 3‐bpd ligands in 1 adopt a monodentate binding mode and the dpe in 2 adopts a bismonodentate bridging mode to connect the Mn(II) ions forming a 1D chain‐like coordination polymer. Both the π‐π stacking interactions between the coordinated and the free pyridyl‐based ligands and intermolecular hydrogen bonds among the coordinated and the crystallized water molecules and the free pyridyl‐based ligands play an important role in construction of these 3D supramolecular architectures.  相似文献   

19.
The Lanthanum Dodecahydro‐closo‐Dodecaborate Hydrate [La(H2O)9]2[B12H12]3·15 H2O and its Oxonium‐Chloride Derivative [La(H2O)9](H3O)Cl2[B12H12]·H2O By neutralization of an aqueous solution of the free acid (H3O)2[B12H12] with basic La2O3 and after isothermic evaporation colourless, face‐rich single crystals of a water‐rich lanthanum(III) dodecahydro‐closo‐dodecaborate hydrate [La(H2O)9]2[B12H12]3·15 H2O are isolated. The compound crystallizes in the trigonal system with the centrosymmetric space group (a = 1189.95(2), c = 7313.27(9) pm, c/a = 6.146; Z = 6; measuring temperature: 100 K). The crystal structure of [La(H2O)9]2[B12H12]3·15 H2O can be characterized by two of each other independent, one into another posed motives of lattice components. The [B12H12]2− anions (d(B–B) = 177–179 pm; d(B–H) = 105–116 pm) are arranged according to the samarium structure, while the La3+ cations are arranged according to the copper structure. The lanthanum cations are coordinated in first sphere by nine oxygen atoms from water molecules in form of a threecapped trigonal prism (d(La–O) = 251–262 pm). A coordinative influence of the [B12H12]2− anions on La3+ has not been determined. Since “zeolitic” water of hydratation is also present, obviously the classical H–Oδ–···H–O‐hydrogen bonds play a significant role in the stabilization of the crystal structure. During the conversion of an aqueous solution of (H3O)2[B12H12] with lanthanum trichloride an anion‐mixed salt with the composition [La(H2O)9](H3O)Cl2[B12H12]·H2O is obtained. The compound crystallizes in the hexagonal system with the non‐centrosymmetric space group (a = 808.84(3), c = 2064.51(8) pm, c/a = 2.552; Z = 2; measuring temperature: 293 K). The crystal structure can be characterized as a layer‐like structure, in which [B12H12]2− anions and H3O+ cations alternate with layers of [La(H2O)9]3+ cations (d(La–O) = 252–260 pm) and Cl anions along [001]. The [B12H12]2− (d(B–B) = 176–179 pm; d(B–H) = 104–113 pm) and Cl anions exhibit no coordinative influence on La3+. Hydrogen bonds are formed between the H3O+ cations and [B12H12]2− anions, also between the water molecules of [La(H2O)9]3+ and Cl anions, which contribute to the stabilization of the crystal structure.  相似文献   

20.
Crystal Structure of Sodium Dihydrogencyamelurate Tetrahydrate Na[H2(C6N7)O3] · 4 H2O Sodium dihydrogencyamelurate‐tetrahydrate Na[H2(C6N7)O3]·4 H2O was obtained by neutralisation of an aqueous solution, previously prepared by hydrolysis of the polymer melon with sodium hydroxide. The crystal structure was solved by single‐crystal X‐ray diffraction ( a = 6.6345(13), b = 8.7107(17), c = 11.632(2) Å, α = 68.96(3), β = 87.57(3), γ = 68.24(3)°, V = 579.5(2) Å3, Z = 2, R1 = 0.0535, 2095 observed reflections, 230 parameters). Both hydrogen atoms of the dihydrogencyamelurate anion are directly bound to nitrogen atoms of the cyameluric nucleus, thus proving the preference of the keto‐tautomere in salts of cyameluric acid in the solid‐state. The compound forms a layer‐like structure with an extensive hydrogen bonding network.  相似文献   

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