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1.
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   

2.
During the reaction of an aqueous solution of (H3O)2[B12H12] with Tl2CO3 anhydrous thallium(I) dodecahydro‐closo‐dodecaborate Tl2[B12H12] is obtained as colorless, spherical single crystals. It crystallizes in the cubic system with the centrosymmetric space group Fm$\bar{3}$ (a = 1074.23(8) pm, Z = 4) in an anti‐CaF2 type structure. Four quasi‐icosahedral [B12H12]2– anions (d(B–B) = 180–181 pm, d(B–H) = 111 pm) exhibit coordinative influence on each Tl+ cation and provide a twelvefold coordination in the shape of a cuboctahedron (d(Tl–H) = 296 pm). There is no observable stereochemical activity of the non‐bonding electron pairs (6s2 lone pairs) at the Tl+ cations. By neutralization of an aqueous solution of the acid (H3O)2[B12H12] with PbCO3 and after isothermic evaporation colorless, plate‐like single crystals of lead(II) dodecahydro‐closo‐dodecaborate hexahydrate Pb(H2O)3[B12H12] · 3H2O can be isolated. This compound crystallizes orthorhombically with the non‐centrosymmetric space group Pna21 (a = 1839.08(9), b = 1166.52(6), c = 717.27(4) pm, Z = 4). The crystal structure of Pb(H2O)3[B12H12] · 3H2O is characterized as a layer‐like arrangement. The Pb2+ cations are coordinated in first sphere by only three oxygen atoms from water molecules (d(Pb–O) = 247–248 pm). But a coordinative influence of the [B12H12]2– anions (d(B–B) = 173–181 pm, d(B–H) = 93–122 pm) on lead has to be stated, too, as three hydrogen atoms from three different hydroborate anions are attached to the Pb2+ cations (d(Pb–H) = 258–270 pm) completing their first‐sphere coordination number to six. These three oxygen and three hydrogen ligands are arranged as quite irregular polyhedron leaving enough space for a stereochemical lone‐pair activity (6sp) at each Pb2+ cation. Since additional intercalating water of hydration is present as well, both classical H–Oδ ··· +δH–O‐ and unconventional B–Hδ ··· +δH–O hydrogen bonds play a significant role in the stabilization of the entire crystal structure.  相似文献   

3.
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   

4.
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   

5.
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   

6.
Synthesis and Crystal Structure of Cadmium Dodecahydro closo‐Dodecaborate Hexahydrate, Cd(H2O)6[B12H12] Through neutralization of the aqueous free acid (H3O)2[B12H12] with cadmium carbonate (CdCO3) and after isothermic evaporation of the resulting solution, colourless lath‐shaped single crystals of Cd(H2O)6[B12H12] are obtained. Cadmium dodecahydro closo‐dodecaborate hexahydrate crystallizes at room temperature in the monoclinic system (space group: C2/m) with the lattice constants a = 1413.42(9), b = 1439.57(9), c = 749.21(5) pm and β = 97.232(4)° (Z = 4). The crystal structure of Cd(H2O)6[B12H12] can be regarded as a monoclinic distortion variant of the CsCl‐type structure. Two crystallographically different [Cd(H2O)6]2+ octahedra (d(Cd–O) = 227–230 pm) are present which only differ in their relative orientation. The intramolecular bond lengths for the quasi‐icosahedral [B12H12]2? cluster anions range in the intervals usually found for dodecahydro closo‐dodecaborates (d(B–B) = 177–179 pm, d(B–H) = 103–116 pm). The hydrogen atoms of the [B12H12]2? clusters have no direct coordinative influence on the Cd2+ cations. Due to the fact that no “zeolitic” crystal water molecules are present, a stabilization of the lattice takes place mainly via the B–Hδ?···H–O hydrogen bonds.  相似文献   

7.
Investigations on the Crystal Structure of Lithium Dodecahydro‐closo‐dodecaborate from Aqueous Solution: Li2(H2O)7[B12H12] By neutralization of an aqueous solution of the acid (H3O)2[B12H12] with lithium hydroxide (LiOH) and subsequent isothermic evaporation of the resulting solution to dryness, it was possible to obtain the heptahydrate of lithium dodecahydro‐closo‐dodecaborate Li2[B12H12] · 7 H2O (≡ Li2(H2O)7[B12H12]). Its structure has been determined from X‐ray single crystal data at room temperature. The compound crystallizes as colourless, lath‐shaped, deliquescent crystals in the orthorhombic space group Cmcm with the lattice constants a = 1215.18(7), b = 934.31(5), c = 1444.03(9) pm and four formula units in the unit cell. The crystal structure of Li2(H2O)7[B12H12] can not be described as a simple AB2‐structure type. Instead it forms a layer‐like structure analogous to the well‐known barium compound Ba(H2O)6[B12H12]. Characteristic feature is the formation of isolated cation pairs [Li2(H2O)7]2+ in which the water molecules form two [Li(H2O)4]+ tetrahedra with eclipsed conformation, linked to a dimer via a common corner. The bridging oxygen atom (∢(Li‐ O ‐Li) = 112°) thereby formally substitutes Ba2+ in Ba(H2O)6[B12H12] according to (H2 O )Li2(H2O)6[B12H12]. A direct coordinative influence of the [B12H12]2— cluster anions to the Li+ cations is not noticeable, however. The positions of the hydrogen atoms of both the water molecules and the [B12H12]2— units have all been localized. In addition, the formation of B‐Hδ—···δ+H‐O‐hydrogen bonds between the water molecules and the hydrogen atoms from the anionic [B12H12]2— clusters is considered and their range and strength is discussed. The dehydratation of the heptahydrate has been investigated by DTA‐TG measurements and shown to take place in two steps at 56 and 151 °C, respectively. Thermal treatment leads to the anhydrous lithium dodecahydro‐closo‐dodecaborate Li2[B12H12], eventually.  相似文献   

8.
Chemical and Cyclovoltammetric Investigation of the Redoxreactions of the Decahalodecaborates closo ‐[B10X10]2– and hypercloso ‐[B10X10]· – (X = Cl, Br)1). Crystal Structure Analysis of Cs2[B10Br10] · 2 H2O The oxidation of the decachloro‐closo‐decaborates(2–) Cs2[B10Cl10] or [Me4N]2[B10Cl10] with Tl(CF3COO)3 leads to the corresponding radical monoanion hypercloso‐[B10Cl10] · –, which was characterized by ESR and UV/Vis spectroscopy. [B10Cl10] · – does not dimerize like [B10H10] · – but it is reduced by acetonitrile to the dianion [B10Cl10]2–. Cs2[B10Cl10] reacts with stronger oxidation agents like CoF3 (in dichloromethane) or XeF2 (in perfluorhexane), respectively, to yield B9Cl9 and, in traces, B8Cl8. In opposite to this, the decabromoderivative Cs2[B10Br10] does not show any reaction with Tl(CF3COO)3 in acetonitrile or with CoF3 in CH2Cl2. The oxidation of the dianions [B10X10]2– (X = Cl, Br) was studied by electroanalytical methods (cyclic voltammetry, chronoamperometry, chronocoulometry). Formal potentials were determined for the two steps of the reaction, which do not seem to be affected by structural rearrangements. The crystal structure of Cs2[B10Br10] · 2 H2O was analyzed by single‐crystal X‐ray diffraction. Cs2[B10Br10] · 2 H2O crystallizes monoclinic (space group I2/a, (no. 15), Z = 8, a = 1361.54(9) pm, b = 1215.89(5) pm, c = 3108.4(2) pm, α = 90°, β = 97.916(8)°, γ = 90°). The closo‐cluster B10Br102– has a bicapped square antiprismatic structure with idealized D4d symmetry.  相似文献   

9.
Colourless, lath‐shaped single crystals of Cs2[B12I12] · 2 CH3CN (monoclinic, C2/m; a = 1550.3(2), b = 1273.2(1), c = 1051.5(1) pm, β = 120.97(1)°; Z = 2) are obtained by the reaction of Cs2[B12H12] with an excess of I2 and ICl (molar ratio: 1 : 2) in methylene iodide (CH2I2) at 180 °C (8 h) and recrystallization of the crude product from acetonitrile (CH3CN). The crystal structure contains quasi‐icosahedral [B12I12]2– anions (d(B–B) = 176–182 pm, d(B–I) = 211–218 pm) which arrange in a cubic closest‐packed fashion. All octahedral interstices are filled with centrosymmetric dimer‐cations {[Cs(N≡C–CH3)]2}2+ containing a diamond‐shaped four‐membered (Cs–N–Cs–N) ring of Cs+ cations and nitrogen atoms of the solvating acetonitrile molecules (d(Cs–N) = 321 pm, 2 ×). The cesium cations themselves actually reside in the distorted tetrahedral voids of the cubic [B12I12]2– packing (d(Cs–I) = 402–461 pm, 10 ×) if one ignores the solvent particles.  相似文献   

10.
Colourless octahedral single crystals of solvent‐free Ag2[B12Cl12] (cubic, Pa3¯; a = 1238.32(7) pm, Z = 4) are obtained by the metathesis reaction of Cs2[B12Cl12] with an aqueous solution of silver nitrate (AgNO3) and recrystallization of the crude product from water. The crystal structure is best described as a distorted anti‐CaF2‐type arrangement in which the quasi‐icosahedral [B12Cl12]2— anions (d(B—B) = d(B—Cl) = 177—180 pm) are arranged in a cubic closest‐packed fashion. The tetrahedral interstices are filled with Ag+ cations which are strongly displaced from their ideal positions. Thereby each silver atom gets coordinated by six chlorine atoms from the edges of three [B12Cl12]2— anions providing a distorted octahedral coordination sphere to the Ag+ cations (d(Ag—Cl) = 283—285 pm, CN = 6).  相似文献   

11.
Structural Investigations on Cs2[B12H12] The crystal structure of Cs2[B12H12] has been determined from X‐ray single‐crystal data collected at room temperature. Dicesium dodecahydro‐closo‐dodecaborate crystallizes as colourless, face‐rich crystals (cubic, Fm 3; a = 1128.12(7) pm; Z = 4). Its synthesis is based on the reaction of Na[BH4] with BF3(O(C2H5)2) via the decomposition of Na[B3H8] in boiling diglyme, followed by subsequent separations, precipitations (with aqueous CsOH solution) and recrystallizations. The crystal structure is best described as anti‐CaF2‐type arrangement with the Cs+ cations in all tetrahedral interstices of the cubic closest‐packed host lattice of the icosahedral [B12H12]2–‐cluster dianions. The intramolecular bond lengths are in the range usually found in closo‐hydroborates: 178 pm for the B–B and 112 pm for the B–H distance. Twelve hydrogen atoms belonging to four [B12H12]2– icosahedra provide an almost perfect cuboctahedral coordination sphere to the Cs+ cations, and their distance of 313 pm (12 ×) attests for the salt‐like character of Cs2[B12H12] according to {(Cs+)2([B12H12]2–)}. The 11B{1H}‐NMR data in aqueous (D2O) solution are δ = –12,70 ppm (1JB–H = 125 Hz), and δ = –15,7 ppm (linewidth: δν1/2 = 295 Hz) for the solid state 11B‐MAS‐NMR.  相似文献   

12.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

13.
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   

14.
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   

15.
Bis(tetramethylammonium) dodecahydrododecaborate, [(CH3)4N]2[B12H12], and bis(tetramethylammonium) dodecahydrododecaborate acetonitrile, [(CH3)4N]2[B12H12] · CH3CN, were synthesized and characterized via Infrared, 1H and 11B NMR spectroscopy. [(CH3)4N]2[B12H12] crystallizes isopunctual to the alkali metal dodecaborates. The crystal structure of [(CH3)4N]2[B12H12] · CH3CN was determined from single crystal data and refined in the orthorhombic crystal system (Pcmn, no. 62, a = 898.68(8), b = 1312.85(9) c = 1994.5(1) pm, R(|F| , 4σ) = 5.9%, wR(F2) = 18.3%). Here, the geometry of the dodecaborate anion is that of an almost ideal icosahedron, less distorted than most other dodecaborates known. By low‐temperature Guinier‐Simon diffractometry phase transitions were detected for [(CH3)4N]2[B12H12] and [(CH3)4N]2[B12H12] · CH3CN at –70 and –15 °C, respectively.  相似文献   

16.
The characteristic feature of the structure of the title compound, dipotassium bis(sulfito‐κS)mercurate(II) 2.25‐hydrate, is a layered arrangement parallel to (001) where each of the two independent [Hg(SO3)2]2− anions are grouped into centrosymmetric pairs and are surrounded by two K+ cations to give the overall layer composition {K2[Hg(SO3)2]2}2−. The remaining cations and the uncoordinated water molecules are situated between these layers. Within the [Hg(SO3)2]2− anions, the central Hg atoms are twofold coordinated by S atoms, with a mean Hg—S bond length of 2.384 (2) Å. The anions are slightly bent [174.26 (3) and 176.99 (3)°] due to intermolecular O...Hg interactions greater than 2.8 Å. All coordination polyhedra around the K+ cations are considerably distorted, with coordination numbers ranging from six to nine. Although the H atoms of the five water molecules (one with symmetry 2) could not be located, O...O separations between 2.80 and 2.95 Å suggest a system of medium to weak O—H...O hydrogen bonds which help to consolidate the structural set‐up. Differences and similarities between the bis(sulfito‐κS)mercurate(II) anions in the title compound and those in the related salts (NH4)2[Hg(SO3)2] and Na2[Hg(SO3)2]·H2O are discussed.  相似文献   

17.
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   

18.
The new hexathiodiphosphate(IV) hydrates K4[P2S6] · 4 H2O ( 1 ), Rb4[P2S6] · 6 H2O ( 2 ), and Cs4[P2S6] · 6 H2O ( 3 ) were synthesized by soft chemistry reactions from aqueous solutions of Na4[P2S6] · 6 H2O and the corresponding heavy alkali‐metal hydroxides. Their crystal structures were determined by single crystal X‐ray diffraction. K4[P2S6] · 4 H2O ( 1 ) crystallizes in the monoclinic space group P 21/n with a = 803.7(1), b = 1129.2(1), c = 896.6(1) pm, β = 94.09(1)°, Z = 2. Rb4[P2S6] · 6 H2O ( 2 ) crystallizes in the monoclinic space group P 21/c with a = 909.4(2), b = 1276.6(2), c = 914.9(2) pm, β = 114.34(2)°, Z = 2. Cs4[P2S6] · 6 H2O ( 3 ) crystallizes in the triclinic space group with a = 742.9(2), b = 929.8(2), c = 936.8(2) pm, α = 95.65(2), β = 112.87(2), γ = 112.77(2)°, Z = 1. The structures are built up by discrete [P2S6]4? anions in staggered conformation, the corresponding alkali‐metal cations and water molecules. O ··· S and O ··· O hydrogen bonds between the [P2S6]4? anions and the water molecules consolidate the structures into a three‐dimensional network. The different water‐content compositions result by the corresponding alkali‐metal coordination polyhedra and by the prefered number of water molecules in their coordination sphere, respectively. The FT‐Raman and FT‐IR/FIR spectra of the title compounds have been recorded and interpreted, especially with respect to the [P2S6]4? group. The thermogravimetric analysis showed that K4[P2S6] · 4 H2O converted to K4[P2S6] as it was heated at 100 °C.  相似文献   

19.
Crystal Structures of Octacyanomolybdates(IV). IV Dodecahedral [Mo(CN)8] Coordination of the Cyano‐Bridged Cobalt and Nickel Ammin Complexes MII2(NH3)8[Mo(CN)8] · 1.5 H2O (MII = Co, Ni) and Ni2(NH3)9[Mo(CN)8] · 2 H2O At single crystals of the hydrated cyano complexes Co2(NH3)8[Mo(CN)8] · 1.5 H2O (a = 910.0(4), b = 1671(2), c = 1501(1) pm, β = 93.76(6)°) and Ni2(NH3)8[Mo(CN)8] · 1.5 H2O (a = 899.9(9), b = 1654.7(4), c = 1488(1) pm, β = 94.01°), isostructurally crystallizing in space group P21/c, Z = 4, and of trigonal Ni2(NH3)9[Mo(CN)8] · 2 H2O (a = 955.1(1), c = 2326.7(7) pm, P31, Z = 3), X‐ray structure determinations were performed at 168 resp. 153 K. The [Mo(CN)8]4– groups of the three compounds, prepared at about 275 K and easily decomposing, show but slightly distorted dodecahedral coordination (mean distances Mo–C: 216.3, 215.4 and 216.1 pm). Within the monoclinic complexes the anions twodimensionally form cyano bridges to the ammin cations [M(NH3)4]2+ and are connected with the resulting [MN6] octahedra (Co–N: 215.1 pm, Ni–N: 209.8 pm) into strongly puckered layers. The trigonal complex exhibits a chain structure, as one [Ni(NH3)5]2+ cation is only bound as terminal octahedron (Ni–N: 212.0 pm). Details and the influence of hydrogen bridges are discussed.  相似文献   

20.
The deprotonation of the nido‐anion [B11H14] by two equivalents of LitBu yields the anion [B11H12]3–. Three observed 11B NMR shifts of this anion in the ratio 1 : 5 : 5 are in agreement with shifts calculated by the GIAO method on the basis of the ab initio computed geometry. The deprotonation can be reversed, giving back [B11H14] via [B11H13]2–. The thermolysis of [Li(thp)x]3[B11H12] in thp at 80 °C leads to the closo‐borate [Li(thp)3]2[B11H11] under elimination of LiH. Anhydrous air transforms [B11H12]3– into the known oxa‐nido‐dodecaborate [OB11H12]. The rhoda‐closo‐dodecaborate [L2RhB11H11]3– is formed from [B11H12]3– and RhL3Cl (L = PPh3).  相似文献   

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