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1.
Two new borosulfates were obtained either by an open vessel synthesis from sulfuric acid and B(OH)3, yielding (NH4)3[B(SO4)3] or from solvothermal synthesis in oleum enriched sulfuric acid and B(OH)3, yielding Sr[B2(SO4)4]. (NH4)3[B(SO4)3] crystallizes homeotypic to K3[B(SO4)3] in space group Ibca (Z = 8, a = 728.58(3) pm, b = 1470.84(7) pm, c = 2270.52(11) pm), comprising open branched vierer single chains {1[B(SO4)2(SO4)2/2]3–}. Sr[B2(SO4)4] crystallizes as an ordered variant of Pb[B2(SO4)4] in space group Pnna (Z = 4, a = 1257.4(4) pm, b = 1242.1(4) pm, c = 731.9(2) pm), consisting of loop branched vierer single chains {1[B(SO4)4/2]2–}. Vibrational spectroscopy confirms both refined structure models. Thermal analysis of the dried powders, showed a decomposition towards the binary and ternary components, whereas a thermal treatment in the presence of the mother liquor promotes a decomposition of Sr[B2(SO4)4] towards Sr[B2O(SO4)3].  相似文献   

2.
Single crystals of mercury(II) polyphosphate, Hg(PO3)2, were prepared from HgO in an acidic polyphosphate melt. The structure is isotypic with α‐Cd(PO3)2 and comprises infinite polyphosphate chains with a period of four phosphate units. Chains of the form 1[PO3?] are linked by Hg2+ to form a three‐dimensional network. The Hg atom is located at the centre of a distorted octahedron of O atoms with distances 2.173 (5) < (Hg—O)mean < 2.503 (6) Å. The [HgO6] polyhedra form zigzag‐like chains of the form 1[HgO2O4/2] parallel to the c axis.  相似文献   

3.
Tetraethylphosphonium azide, [P(C2H5)4 ]+[N3 ], was prepared from tetraethyl phosphonium bromide and silver azide. Single crystals of [P(C2H5)4 ]+[N3 ] were grown from dichloromethane/THF (10:1) solution. The structure was determined by single-crystal X-ray diffraction analysis. [P(C2H5)4 ]+[N3 ] crystallizes in the monoclinic space group C 2/c with Z = 4 and unit cell dimensions a = 12.961(6), b = 6.835(3), c = 12.378(6) Å, and β = 100.57(4)°. The attempted preparation of phosphonium azide [PH4]+[N3] from phosphonium iodide and silver azide lead instead to the formation of PH3 and HN3. The instability of [PH4]+[N3] with respect to PH3 and HN3 is in accord with thermodynamic considerations according to which the reaction PH3(g) and HN3(g) to yield [PH4 ]+[N3 ] is thermodynamically unfavorable. (Non SI units employed: kcal ≈ 4.184 J, Å = 10−10 m.) © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:129–132, 1998  相似文献   

4.
Crystalline NO2[Fe(NO3)4] was obtained by dehydration of a solution of Fe(NO3)3 in 100 % HNO3 and subsequent sublimation. NO2[Zr(NO3)5] was synthesized by reaction of ZrCl4 with N2O5 followed by sublimation in vacuum. X‐ray single crystal structure determination showed both compounds to consist of nitronium cations, NO2+, and nitratometalate anions. N‐O distances in the linear NO2+ cations are in the range of 1.08—1.13Å. In both [Fe(NO3)4] and [Zr(NO3)5] anions, all nitrate groups are coordinated bidentately with average M‐O distances 2.134 and 2.293Å, respectively. Taking into account the position of N atoms around the M atoms, the arrangement of nitrate groups can be described as tetrahedral for the Fe complex and trigonal‐bipyramidal for the Zr complex. There are four shortest N(nitronium)····O(nitrate group) contacts with average distances of 2.705 and 2.726Å in NO2[Fe(NO3)4] and 2.749Å in NO2[Zr(NO3)5]. Nitronium pentanitratohafnate is isotypic to the zirconium complex.  相似文献   

5.
(OLi2Ca4)3[ReN4]4, a Nitridorhenate(VI) Oxide Black single crystals of (OLi2Ca4)3[ReN4]4 were prepared from the elements (molar ratio Li : Ca : Re = 6 : 1 : 1) by reaction with molecular nitrogen at 900 °C; oxygen content results from a leak in the gas supply. The nitridorhenate(VI)‐oxide is an isotype of (OLi2Ca4)3[MN4]4 (M = MoVI, WVI). These compounds are obtained under similar reaction conditions in the presence of small amounts of oxygen containing impurities (Li‐/Ca‐hydroxides). The crystal structure of (OLi2Ca4)3[ReN4]4 was determined by single crystal methods (cubic; I43d (# 220); a = 1315.88(9) pm; Z = 4) and can be derived from the Th3P4 type structure by hierarchical replacements: Th ≙ (OLi2Ca4)8+‐tetragonal bipyramids and P ≙ [ReVIN4]6–‐tetrahedra.  相似文献   

6.
Simple Trithio- and Perthiocarbonato Complexes with Interesting Bond Properties: [E(CS3)2]2? (E = Sn, Zn, Cd), [E(CS3)3]3? (E = As, Sb, Bi, Co), {Cu(CS3)?} and [Zn(CS4)2]2? By reactions of potassium trithiocarbonate ( 1 ) with solutions of zinc(II)- acetylacetonate, cadmium(II)-chloride, tin(II)-chloride, arsenic(III)-sulfide (suspension), antimony(III)-chloride, bismuth(III)-chloride and copper(II)-chloride in dimethyl sulfoxide, as well as of trisodium hexanitrito cobaltate(III) in water, and the precipitation of the complexes with an aqueous solution of tetraphenylphosphonium chloride the compounds (PPh4)2[Zn(CS3)2] ( 2 ), (PPh4)2[Cd(CS3)2] ( 3 ), (PPh4)2[Sn(CS3)2] ( 4 ), (PPh4)3[As(CS3)3] ( 5 ), (PPh4)3[Sb(CS3)3] ( 6 ), (PPh4)3[Bi(CS3)3] ( 7 ), (PPh4)3[Co(CS3)3] ( 8 ) and (PPh4)Cu(CS3) ( 9 ) have been isolated. (PPh4)2[Zn(CS4)2] · CH3NO2 ( 10 ) has been prepared by heating a solution of 2 in nitromethane to 60--70°C in presence of air. The reaction of 1 in dimethyl sulfoxide with an aqueous tetraphenylphosphonium chloride solution in presence of oxygen leads to (PPh4)2[C2S6] ( 11 ). The compounds have been characterized by spectroscopical studies (IR, Raman, UV/Vis, 113Cd/59Co-NMR), magnetic susceptibility measurements, powder diffractometry, elemental analyses and single crystal X-ray structure analysis ( 4 – 7 , 10 and 11 ). The difficult growing of single crystals has been reported in detail. For crystal data see Inhaltsübersicht.  相似文献   

7.
Several new donor–acceptor adducts of niobium and tantalum pentaazide with N‐donor ligands have been prepared from the pentafluorides by fluoride–azide exchange with Me3SiN3 in the presence of the corresponding donor ligand. With 2,2′‐bipyridine and 1,10‐phenanthroline, the self‐ionization products [MF4(2,2′‐bipy)2]+[M(N3)6], [M(N3)4(2,2′‐bipy)2]+[M(N3)6] and [M(N3)4(1,10‐phen)2]+[M(N3)6] were obtained. With the donor ligands 3,3′‐bipyridine and 4,4′‐bipyridine the neutral pentaazide adducts (M(N3)5)2⋅L (M=Nb, Ta; L=3,3′‐bipy, 4,4′‐bipy) were formed.  相似文献   

8.
Infrared photodissociation spectroscopy of mass‐selected heteronuclear cluster anions in the form of OMFe(CO)5 (M=Sc, Y, La) indicates that all these anions involve an 18‐electron [Fe(CO)4]2− building block that is bonded with the M center through two bridged carbonyl ligands. The OLaFe(CO)5 anion is determined to be a CO‐tagged complex involving a [Fe(CO)4]2−[LaO]+ anion core. In contrast, the OYFe(CO)5 anion is characterized to have a [Fe(CO)4]2−[Y(η2‐CO2)]+ structure involving a side‐on bonded CO2 ligand. The CO‐tagged complex and the [Fe(CO)4]2−[Sc(η2‐CO2)]+ isomer co‐exist for the OScFe(CO)5 anion. These observations indicate that both the ScO+ and YO+ cations supported on [Fe(CO)4]2− are able to oxidize CO to CO2. Theoretical analyses show that [Fe(CO)4]2− coordination significantly weakens the MO+ bond and decreases the energy gap of the interacting valence orbitals between MO+ and CO, leading to the CO oxidation reactions being both thermodynamically exothermic and kinetically facile.  相似文献   

9.
The complexes Ag(L)n[WCA] (L=P4S3, P4Se3, As4S3, and As4S4; [WCA]=[Al(ORF)4] and [F{Al(ORF)3}2]; RF=C(CF3)3; WCA=weakly coordinating anion) were tested for their performance as ligand-transfer reagents to transfer the poorly soluble nortricyclane cages P4S3, P4Se3, and As4S3 as well as realgar As4S4 to different transition-metal fragments. As4S4 and As4S3 with the poorest solubility did not yield complexes. However, the more soluble silver-coordinated P4S3 and P4Se3 cages were transferred to the electron-poor Fp+ moiety ([CpFe(CO)2]+). Thus, reaction of the silver salt in the presence of the ligand with Fp−Br yielded [Fp−P4S3][Al(ORF)4] ( 1 a ), [Fp−P4S3][F(Al(ORF)3)2] ( 1 b ), and [Fp−P4Se3][Al(ORF)4] ( 2 ). Reactions with P4S3 also yielded [FpPPh3−P4S3][Al(ORF)4] ( 3 ), a complex with the more electron-rich monophosphine-substituted Fp+ analogue [FpPPh3]+ ([CpFe(PPh3)(CO)]+). All complex salts were characterized by single-crystal XRD, NMR, Raman, and IR spectroscopy. Interestingly, they show characteristic blueshifts of the vibrational modes of the cage, as well as structural contractions of the cages upon coordination to the Fp/FpPPh3 moieties, which oppose the typically observed cage expansions that lead to redshifts in the spectra. Structure, bonding, and thermodynamics were investigated by DFT calculations, which support the observed cage contractions. Its reason is assigned to σ and π donation from the slightly P−P and P−E antibonding P4E3-cage HOMO (e symmetry) to the metal acceptor fragment.  相似文献   

10.
Diffusion of aqueous solutions of K4[Re4Te4(CN)12] and CuCl2 in the opposite direction through silica gel gives rise to the new polymer-like compound 1 . This complex has a layered structure built from the interconnected cubane-like cluster cations [Cu4(μ3-OH)4]4+ and the cluster anions [Re4Te4(CN)12]4− (see picture).  相似文献   

11.
Syntheses and Structures of (Et4N)2[Re(CO)3(NCS)3] and (Et4N)[Re(CO)2Br4] Rhenium(I) and rhenium(III) carbonyl complexes can easily be prepared by ligand exchange reactions starting from (Et4N)2[Re(CO)3Br3]. Using nonoxidizing reagents the facial ReI(CO)3 unit remains and only the bromo ligands are exchanged. Following this procedure, (Et4N)2[Re(CO)3(NCS)3] can be obtained in high yield and purity using trimethylsilylisothiocyanate. The compound crystallizes in the monoclinic space group P21/n, a = 18.442(5), b = 17.724(3), c = 18.668(5) Å, β = 92.54(1)°, Z = 8. The NCS? ligands are coordinated via nitrogen. The reaction of [Re(CO)3Br3]2? with Br2 yields the rhenium(III) anion [Re(CO)2Br4]?. The tetraethylammonium salt of this complex crystallizes in the noncentrosymmetric, orthorhombic space group Cmc21, a = 8.311(1), b = 25.480(6), c = 8.624(1) Å, Z = 4. The carbonyl ligands are positioned in a cis arrangement. Their strong trans influence causes a lengthening of the Re? Br bond distances by at least 0.05 Å.  相似文献   

12.
The reaction of diaminotetrachloro-cyclotriphosphazene with tetrachloride of μ-imino-diphosphoric acid leads to the formation of the salt-like compound [P3N3HCl4(NH2)2]+[N(POCl2)2] which identity was unambiguously established by means of X-ray structure analysis. The structure is composed of [P3N3HCl4(NH2)2]+ cations and [N(POCl2)2] anions joined by a system of H-bonds. As in other phosphazenium salts, the protonation of the ring N atom leads to significant changes in the endocyclic P N bond lengths.  相似文献   

13.
Tetraphenylarsonium azide was prepared from the reaction of tetraphenylarsonium chloride monohydrate and sodium azide in aqueous solution. [Ph4As]+[N3] crystallizes in the orthorhombic space group Pnma with Z = 4 and unit cell dimensions a = 16.539(2), b = 10.879(2), and c = 12.671(2) Å. The preparation of the compound [Ph4As]+[SCSN3] was also attempted; however, it was found that at temperatures ≥0°C, this compound always decomposed into the tetraphenylarsonium thiocyanate, [Ph4As]+[SCN]. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 325–329, 1999  相似文献   

14.
Preparation and Structure of (4-Picolinium)2[LnCl4(H2O)3]Cl (Ln = Eu, Ho) The complex water containing chlorides (4-Picolinium)2[LnCl4(H2O)3]Cl (Ln = Eu, Ho) were prepared for the first time. The crystal structures were determined on single crystals by X-ray methods. The isotypic compounds crystallize with triclinic symmetry, space group P–1, Z = 2. Surprisingly the structures contain the complex anions [LnCl4(H2O)3]? (Ln = Eu, Ho) where the ligands form a distorted pentagonal bipyramid, which to our knowledge has not been observed in lanthanide compounds till now.  相似文献   

15.
Abstract

1-D coordination polymers, 1[Zn(fl)2]·2EtOH and 1[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip?= N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400?°C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated.  相似文献   

16.
Azido Complexes of Zirconium: ZrCl3N3, [ZrCl4N3]22?, [ZrCl4(N3)2]2?; Crystal Structure of (PPh4)2 [ZrCl4N3]2 Highly explosive ZrCl3N3 is formed by the reaction of ZrCl4 with iodine azide in dichloromethane suspension. According to the i.r. spectra, the compound is polymeric by azide and chlorine bridges. Zirconium tetrachloride reacts with one and two moles of tetraphenylphosphonium azide respectively, forming the thermally and mechanically stable complexes (PPh4)2[ZrCl4N3]2 and (PPh4)2[ZrCl4(N3)2]. The crystal structure of (PPh4)2[ZrCl4N3]2 was determined by X-ray methods (1942 reflexions, R = 6.5%). The complex crystallizes in the monoclinic space group P21/n with two formula units per unit cell. The structure consists of tetraphenylphosphonium cations and dimeric anions [ZrCl4N3]22?, in which the Zr atoms are linked by the α-N atoms of the azide groups, forming a centrosymmetric Zr2N2 ring with symmetry D2h. According to the i.r. spectra, the azide groups in the complex (PPh4)2[ZrCl4(N3)2] are covalently bonded at the Zr atom in trans positions.  相似文献   

17.
Metal Ampoules as Mini‐Autoclaves: Syntheses and Crystal Structures of [Al(NH3)4Cl2][Al(NH3)2Cl4] and (NH4)2[Al(NH3)4Cl2][Al(NH3)2Cl4]Cl2 The salts [Al(NH3)4Cl2]+[Al(NH3)2Cl4]≡AlCl3 · 3 NH3 ( 1 ) and (NH4+)2[Al(NH3)4Cl2]+[Al(NH3)2Cl4](Cl)2≡ AlCl3 · 3 NH3 · (NH4)Cl ( 2 ) have been obtained as single crystals during the reactions of aluminum and aluminum trichloride, respectively, with ammonium chloride in sealed Monel metal containers. The crystal structure of 1 was determined again [triclinic, P‐1; a = 574.16(10); b = 655.67(12); c = 954.80(16) pm; α = 86.41(2); β = 87.16(2); γ = 84.89(2)°], that of 2 for the first time [monoclinic, I2/m; a = 657.74(12); b = 1103.01(14); c = 1358.1(3) pm; β = 103.24(2)°].  相似文献   

18.
Structurally Chemical Investigation of Monoammin Copper (I) Complexes : [CuNH3]2[Pt(CN)6], [CuNH3]2[Pt(CN)4] and Cu3[Co(CN)6] · 2NH3 The preparation and the properties of [CuNH3]2[Pt(CN)6], [CuNH3]2[Pt(CN)4] and Cu3[Co(CN)6] · 2NH3 are described. I.R. and Raman spectra have been recorded and assigned. According to X-ray powder diagrams, [CuNH3]2[Pt(CN)6] crystallizes in the trigonal space group D–P3 ml, a = 7.771, c = 5.988 Å, Z = 1. According to the spectroscopic and crystallographic data, it is concluded that the CuI ion is coordinated with one NH3 group and with the N atoms of the cyanometallate anions. The coordination number of the Cu+ is 4 in [CuNH3]2[Pt(CN)6] and 3 in [CuNH3]2[Pt(CN)4]. In the Cu3[Co(CN)6] · 2 NH3 complex two Cu atoms have the coordination number 2, the third Cu atom 4.  相似文献   

19.
Crystal Structure of (NH4)3SnF7: A Double Salt According to (NH4)3[SnF6]F and not (NH4)4SnF8 (NH4)3SnF7 is obtained as colourless single crystals from the reaction of NH4HF2 with tin powder at 300°C. The crystal structure (cubic, Pm3m, Z = 1, a = 602.5(1) pm at 293 K; a = 598.0(1) pm at 100 K) contains [SnF6]2? octahedra and lonesome F? ions surrounded by NH4+ cations only; it may be considered as a derivative of the Cu3Au-type of structure according to Cu3[Au]□ ?(NH4)3[SnF6]F. The F? ions of the [SnF6]2? octahedra with their Sn4+ centre in the origin of the unit cell at m3m are disordered in different ways at 293 and 100 K, respectively.  相似文献   

20.
《Polyhedron》2007,26(9-11):2135-2141
By using broken-symmetry hybrid-DFT (UB3LYP and UB2LYP) calculation, the effective exchange integrals (J values) of [Cr(C5(CH3)5)2]+[TCNE][Cr(C5(CH3)5)2]+ and [Mn(C5(CH3)5)2]+[TCNQ][Mn(C5(CH3)5)2]+ were determined theoretically. Those calculated models were reduced to 3-spin-sites models from X-ray crystallographic data of charge transfer 3D crystal. The calculated results showed that effective exchange integrals were positive and the signs of spin densities on the cyclopentadienyl rings were negative. These results supported the so-called McConnell I mechanism for ferromagnetism proposed by Kollmar et al. and our previous calculations. Natural orbital analysis made it clear that the orbital overlap between SOMO on metals and SOMO on TCNE or TCNQ cations was nearly zero. These results indicated that orbital orthogonality was an important key factor for explaining the ferromagnetism of those systems.  相似文献   

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