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The compound NH4HCN2 ( 1 ) was prepared by the reaction of H2CN2 with liquid ammonia. The ammonium salt 1 was characterized by a low temperature single‐crystal X‐ray structure analysis. The anionic part of the structure consists of HCN2? anions, which are connected via N–H···N bonds (H···N distance: 2.47Å, DHA: 165°). The N–H···N hydrogen bonds of the ammonium ion to the anions range from 2.00 to 2.14Å (DHA = Donor···Acceptor angles: 165–176°), all N–H···N interactions together give rise to a three‐dimensional network. 1 decomposes quantitatively to dicyandiamide at room temperature.  相似文献   

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Some new oxozirconium(IV) complexes: ZrO(An)2, ZrO(Gly)2, ZrO(HSal)2, ZrO(HPth)2, ZrO(Pic)2(HPic)2, and ZrO(Quin)2(H Quin)2 have been isolated from the reactions of ZrO(CH3COO)2CH3COOH with anthranilic acid (HAn), glycine (HGly), salicylic acid (H2Sal), phthalic acid (H2Pth), picolinic acid (HPic), and 8-quinolinol (HQuin) respectively. Their important infrared bands and wherever possible molar conductance and molecular weight have been reported.  相似文献   

5.
Ammonium oxofluorotungstates, (NH4)2WO2F4 and (NH4)3WO3F3, are characterized by vibration spectroscopy and quantum chemistry methods with the use of NMR 19F and 1H data. It is shown in the approximation of the density-functional theory that in isolated octahedrons [WO2F4]2? and [WO3F3]3? the mutual arrangement of oxygen atoms in cis-position corresponds to the energy minimum. The presence of intraspheric disorder in [WO3F3]3? (unlike [WO2F4]2?) explains the complex character of vibrational spectra of this anion and eliminates existent in the literature differences in their interpretation (between C 2v and C 3v structure variants). Models of intraspheric dynamics of [WO3F3]3? are discussed.  相似文献   

6.
Ni(NH3)Cl2 and Ni(NH3)Br2 were prepared by the reaction of Ni(NH3)2X2 with NiX2 at 350 °C in a steel autoclave. The crystal structures were determined by X‐ray powder diffraction using synchrotron radiation and refined by Rietveld methods. Ni(NH3)Cl2 and Ni(NH3)Br2 are isotypic and crystallize in the space group I2/m with Z = 8 and for Ni(NH3)Cl2: a = 14.8976(3) Å, b = 3.56251(6) Å, c = 13.9229(3) Å, β = 106.301(1)°; Ni(NH3)Br2a = 15.5764(1) Å, b = 3.74346(3) Å, c = 14.4224(1) Å, β = 105.894(1)°. The crystal structures are built up by two crystallographically distinct but chemically mostly equivalent polymeric octahedra double chains [NiX3/3X2/2(NH3)] (X = Cl, Br) running along the short b‐axis. The octahedra NiX5NH3 share common edges therein. The crystal structures of the ammines Ni(NH3)mX2 with m = 1, 2, 6 can be derived from that of the halides NiX2 (X = Cl, Br) by successive fragmentation of its CdCl2 like layers by NH3.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

8.
Antimony(m) chlorofluoride complexes M2SbCl3F2 (M = Rb, Cs, or NH4) were studied by the121,123Sb NQR method. A temperature range (77–285 K) with anomalous change in the NQR parameters and a second-order phase transition at 250–280 K for (NH4)2SbCl3F2 were found.Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 382–385, February, 1996  相似文献   

9.
(NH4)2[B2P3O11(OH)] was synthesized as a crystalline colorless powder by reaction of (NH4)2HPO4, H3BO3, and H3PO4 under hydrothermal conditions at 180 °C. According to X‐ray single‐crystal investigations (NH4)2[B2P3O11(OH)] crystallizes in a new structure type in the orthorhombic space group P212121 (no. 19) [Z = 4, a = 4.509(3), b = 14.490(11), c = 16.401(12) Å, R1 = 0.046, wR2 = 0.093, 1682 data, 200 parameters]. The crystal structure comprises infinite layers of corner‐sharing borate, phosphate and hydroxo‐phosphate tetrahedra with ammonium ions in‐between. The loop‐Branched (lB) zweier‐single layer reveals an open‐Branched (oB) vierer‐single ring as fundamental building unit (FBU), which was observed in (NH4)2MnII[B2P3O11(OH)2]Cl[1] for the first time. Besides the spectroscopic properties the thermal behavior is presented as well.  相似文献   

10.
Fluoride and ammonium ion dynamics in (NH4)3Sb4F15 was studied by 1H and 19F NMR spectroscopy in the range 180-440 K. Types of ionic motion were determined, and their activation energies were estimated. The crystal structure of a single crystal of (NH4)3Sb4F15 (space group ) was solved. In the range K, a reversible phase transition has been found. Based on the experimental values of conductivity of (NH4)3Sb4F15 ( S/cm at T = 440 K), this antimony(III) fluoride is classified as a superionic conductor.  相似文献   

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The crystal structure of thallium fluoroantimonate(III) complex TlSb4F13 (I), which is isostructural to KSb4F13 (II), is determined. Crystals I are tetragonal: a = 9.634(2) Å, c = 6.590(2) Å, V = 611.7(2) Å3, Z = 2, (calcd) = 5.094 g/cm3, F(000) = 804.0, space group I4¯. The structure consists of tetrameric [Sb4F13] anions formed by SbF3 groups connected by the fluoride ion and the l+ cations.  相似文献   

12.
用乙二胺作模板剂在水热条件下合成出一个新的三维开放骨架结构的亚磷酸铟[In2(HPO3)4]·(NH3CH2CH2NH3)(1), 并对其晶体结构进行了测定和表征.  相似文献   

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Synthesis of the complex [Rh(NO2)3(NH3)3] is described. The compound crystallizes as monoclinic colorless plates. Crystal data: a = 7.176(10), b = 10.407(2), c = 10.989(2) , = 93.27°, V = 819.3(2) 3, space group , Z = 4, d calc = 2.367 g/cm3. The structure is molecular and built of neutral complexes having cis-facial configuration. The unit cell of the crystal contains two independent complexes.  相似文献   

15.
The compound [NH4(NH3)4][Co(C2B9H11)2] · 2 NH3 ( 1 ) was prepared by the reaction of Na[Co(C2B9H11)2] with a proton‐charged ion‐exchange resin in liquid ammonia. The ammoniate 1 was characterized by low temperature single‐crystal X‐ray structure analysis. The anionic part of the structure consists of [Co(C2B9H11)2] complexes, which are connected via C‐H···H‐B dihydrogen bonds. Furthermore, 1 contains an infinite equation/tex2gif-stack-2.gif[{NH4(NH3)4}+(μ‐NH3)2] cationic chain, which is formed by [NH4(NH3)4]+ ions linked by two ammonia molecules. The N‐H···N hydrogen bonds range from 1.92 to 2.71Å (DHA = Donor···Acceptor angles: 136‐176°). Additional N‐H···H‐B dihydrogen bonds are observed (H···H: 2.3‐2.4Å).  相似文献   

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The α and β modifications of NH4HPO3F were synthesized and characterized with single crystal X‐ray diffraction. The crystal structure of α‐NH4HPO3F determined at 180 K is monoclinic, space group P21/n, with a = 7.4650(1), b = 15.586(2), c = 7.5785(9) Å, β = 108.769(9)°, V = 834.9(2) Å3, Z = 8, and R1 = 0.0376 and wR2 = 0.0818. β‐NH4HPO3F measured at 310 K crystallizes in the triclinic space group, P 1, with a = 7.481(1), b = 7.511(1), c = 7.782(1) Å, α = 84.31(1), β = 84.20(1), γ = 68.67(2)°, V = 404.31(9) Å3, Z = 4, and R1 = 0.0254 and wR2 = 0.0735. A phase transition was not observed between 180 and 310 K for β‐NH4HPO3F. Both modifications of NH4HPO4F consist of HPO3F and NH4+ units. Two pairs of two unique anions are linked to each other by O–H…O hydrogen bonds to form cyclic tetramers held together by N–H…O bonds. No O–H…F or N–H…F bonds were observed.  相似文献   

19.
Synthesis and Crystal Structures of NH4[Si(NH3)F5] and [Si(NH3)2F4] Single crystals of NH4[Si(NH3)F5] and [Si(NH3)2F4] are obtained by reaction of silicon powder with NH4HF2 in sealed Monel ampoules at 400°C. NH4[Si(NH3)F5] crystallizes with the tetragonal space group P4/n (no. 85) with a = 614.91(7) pm, c = 721.01(8) pm, Z = 2. Characteristic for the structure is the anionic octahedron [Si(NH3)F5]?. Si(NH3)2F4 crystallizes with the monoclinic space group P21/c (no. 14) with a = 506.9(1) pm, b = 728.0(1) pm, c = 675.9(1), β = 93,21(2)°, Z = 2. Trans-[Si(NH3)2F4] molecules are characteristic for this structure.  相似文献   

20.
Green single crystals of trans‐tetraamminedibromidochromium(III) trans‐diamminetetrabromidochromate(III), [CrBr2(NH3)4][CrBr4(NH3)2], are found to contain two symmetry‐independent sixfold coordinated CrIII cations on centres of inversion. The structure is composed of octahedral trans‐[CrBr2(NH3)4]+ cations and octahedral trans‐[CrBr4(NH3)2] anions, and adopts a distorted CsCl‐type lattice. The cations and anions are linked by N—H...Br interactions. This is the first example in which both ions are mixed ammine–bromide CrIII complexes.  相似文献   

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