Complex salts [Pd(NH3)4](ReO4)2 and [Pd(NH3)4](MnO4)2: Synthesis, structure, and thermal properties

Complex salts, i.e., tetraamminepalladium perrhenate (I) and permanganate (II), are synthesized and studied by physicochemical methods. Their crystal structures are determined and thermal analysis is performed. The products formed in thermolysis of I and II carried out in the atmosphere of helium and hydrogen are studied. The Pd_0.33Re_0.67 solid solution based on Re is shown to form under particular temperature conditions in the atmosphere of hydrogen.     

Phase transition and dynamics of NH3 ligands in [Zn(NH3)4](ReO4)2

One phase transition in [Zn(NH₃)₄](ReO₄)₂ at T_c = 393.5 K (on heating) and 392.0 K (on cooling) was found. Thermal stability of this compound was investigated by thermal analysis methods. It decomposes in three main stages. The first two are connected with deamination process, whereas Re₂O₇ evaporates in the last step. The activation energy for NH₃ loss processes was determined from thermogravimetric (TG) measurements. The vibrational and reorientational dynamics of NH₃ ligands in the low-temperature phase was probed by various complementary techniques. It was found that at temperatures close to 150 K, NH⋯O hydrogen bond is formed. Temperature-dependent band shape analysis of properly chosen infrared (IR) band was performed, whose results showed that activation energy for NH₃ reorientational motion (<300 K) is rather small and is approximately equal to 2 kJ mol⁻¹. Neutron and X-ray powder diffraction patterns did not reveal any drastic change in the crystal structure in a wide temperature range.     

Synthesis of [M(NH3)5Cl](ReO4)2 (M = Cr, Co, Ru, Rh, Ir) and investigation of thermolysis products. Crystal structure of [Rh(NH3)5Cl](ReO4)2

Complex salts [M(NH₃)₅Cl](ReO₄)₂, where M = Cr, Co, Ru, Rh, Ir, have been prepared. The crystal structure of [Rh(NH₃)₅Cl](ReO₄)₂ was determined by single crystal X-ray diffraction. Crystal data: a = 17.369(4) Å, b = 7.7990(16) Å, c = 11.218(2) Å, V = 1430.5(5) ų, space group C2/m, Z = 4, d _calc = 3.19 g/cm³, R = 0.0447. Complex salts from the above series are shown to be isostructural; they were defined by X-ray crystallography. Thermal decomposition of the compounds in an inert atmosphere and under hydrogen has been studied. According to X-ray phase analysis (XRPA) data, the M_0.33Re_0.67 (M = Co, Ru, Rh, Ir) monophase solid solutions are the products of reduction of the salts under hydrogen.     

Bildung von NH4[Hg3(NH)2](NO3)3 und Umwandlung in [Hg2N](NO3)

Formation of NH₄[Hg₃(NH)₂](NO₃)₃ and Transformation to [Hg₂N](NO₃) NH₄[Hg₃(NH)₂](NO₃)₃ ( 1 ) and [Hg₂N](NO₃) ( 2 ) are obtained from conc. aqueous ammonia solutions of Hg(NO₃)₂ at ambient temperature and under hydrothermal conditions at 180 °C, respectively, as colourless and dark yellow to light brown single crystals. The crystal structures {NH₄[Hg₃(NH)₂](NO₃)₃: cubic, P4₁32, a = 1030.4(2) pm, Z = 4, R_all = 0.028; [Hg₂N](NO₃): tetra gonal, P4₃2₁2, a = 1540.4(1), c = 909.8(1) pm, Z = 4, R_all = 0.054} have been determined from single crystal data. Both exhibit network type structures in which [HNHg₃] and [NHg₄] tetrahedra of the partial structures of 1 and 2 are connected via three and four vertices, respectively. 1 transforms at about 270 °C in a straightforward reaction to 2 whereby the decomposition products of NH₄NO₃ are set free. 2 decomposes at about 380 °C forming yellow HgO. Most certainly, 1 is identical with a mineral previously analyzed as “Hg(NH₂)(NO₃)” with the same Hg:N:O ratio.     

Thermal decomposition of polycrystalline [Ni(NH3)6](NO3)2

The thermal decompositions of polycrystalline samples of [Ni(NH₃)₆](NO₃)₂ were studied by thermogravimetric analysis with simultaneous gaseous products of the decomposition identified by a quadruple mass spectrometer. Two measurements were made for samples placed in alumina crucibles, heated from 303 K up to 773 K in the flow (80 cm³ min^?1) of Ar 6.0 and He 5.0, at a constant heating rate of 10 K min^?1. Thermal decomposition process undergoes two main stages. First, the deamination of [Ni(NH₃)₆](NO₃)₂ to [Ni(NH₃)₂](NO₃)₂ occurs in four steps, and 4NH₃ molecules per formula unit are liberated. Then, decomposition of survivor [Ni(NH₃)₂](NO₃)₂ undergoes directly to the final decomposition products: NiO_1+x, N₂, O₂, nitrogen oxides and H₂O, without the formation of a stable Ni(NO₃)₂, because of the autocatalytic effect of the formed NiO_1+x. Obtained results were compared both with those published by us earlier, by Farhadi and Roostaei-Zaniyani later and also with the results published by Rejitha et al. quite recently. In contradiction to these last ones, in the first and second cases agreement between the results was obtained.     

高氯酸碳酰肼钴、高氯酸碳酰肼镍快速热分解反应动力学

利用温度跃升傅立叶变换红外原位分析技术(T-jump/FTIR)对高氯酸碳酰肼钴和高氯酸碳酰肼镍的快速热分解反应进行了研究. 研究表明, 目标化合物快速热分解逸出的主要气相产物是CO2, H2O, HCN, HNCO和HONO. 借助快速升温过程中Pt金属丝的控制电压变化曲线得到剧烈放热峰的诱导出现时间tx, 利用tx值计算了两种目标化合物的快速热分解动力学参数. 在0.1 MPa氩气气氛, 613～653 K的实验温度范围内, 高氯酸碳酰肼钴的活化能Ea=39.42 kJ•mol−1, lnA=5.93; 在0.1 MPa氩气气氛, 618～678 K的实验温度范围内, 高氯酸碳酰肼镍的活化能Ea=60.44 kJ•mol−1, lnA=9.40.     

Metal solid solutions obtained by thermolysis of Pt and Re salts. Crystal structure of [Pt(NH3)4](ReO4)2

A complex salt of tetraammineplatinum(II) perrhenate [Pt(NH₃)₄](ReO₄)₂ has been synthesized. Crystal data: a = 5.1847(6) Å, b = 7.7397(8) Å, c = 7.9540(9) Å, α = 69.531(3)°, β = 79.656(3)°, γ = 77.649(3)°, V = 290,19(6) ų, space group $P\bar 1$ , Z = 1, d _x = 4.370 g/cm³. The products of decomposition of [Pt(NH₃)₄](ReO₄)₂ in a hydrogen atmosphere were investigated using X-ray phase analysis. In definite temperature modes, these are Pt_0.33Re_0.67 solid solutions based on Re with hcp cell parameters a = 2.76 Å, c = 4.42 Å. The products of thermolysis obtained from other precursor complex salts containing both Pt and Re were investigated. Thus Pt_0.75Re_0.25 solid solution with a = 3.905(3) Å was obtained from (NH₄)₂[ReCl₆]_0.25[PtCl₆]_0.75.     

Synthese und Struktur eines Caesium-tetraimidophosphat-diamids,Cs5[P(NH)4](NH2)2 = Cs3[P(NH)4] · 2 CsNH2

Synthesis and Crystal Structure of a Cesium-tetraimidophosphate-diamide, Cs₅[P(NH)₄](NH₂)₂ = Cs₃[P(NH)₄] · 2 CsNH₂ Well crystallized Cesium-tetraimidophosphate-diamide is obtained by the reaction of CsNH₂ with P₃N₅ in autoclaves at 673 K within three days. X-ray single crystal investigations led to the following data

• Ccca, Z = 4, a = 8.192(5) Å, b = 20.472(5) Å,
• c = 8.252(3) Å
• Z(F) ≥3σ(F) = 916, Z(Var.) = 32, R/R_w=1 = 0.017/0.021

The compound contains the hitherto unknown anion [P(NH)₄]^3?.     

Thermal properties of polycrystalline [Mn(NH3)6](ClO4)2

A flavor precursor α-ionyl-β-d-glucoside (IG) was synthesized by Koenigs–Knorr method, and its structure was characterized by proton nuclear magnetic resonance spectroscopy, Fourier transform-infrared spectroscopy, and electro spray ionization mass spectroscopy (MS). Thermal degradation behaviors of the intermediate α-ionyl-tetra-O-acetyl-β-d-glucoside (IAG) and IG were analyzed by thermogravimetry and online pyrolysis (Py)-gas chromatography–MS. Flavor release property of IG was investigated with cigarettes as the carrier. The results indicated that fracture temperature of glycosidic bond was about 200 °C for IAG, and was about 190 °C for IG. Py of IAG and IG could generate several aroma compounds such as megastigmatriene, α-ionol, α-ionone, and 3-oxo-α-ionol. IG added in cigarettes could be pyrolyzed to release α-ionol, α-ionone, and 3-oxo-α-ionone, and increase the release amount of megastigmatrienone in mainstream smoke during smoking. The release amount of characteristic flavor components in mainstream smoke remain stable after the cigarette sample with IG placed in standard condition for 30 days, and there was no significant difference in the single puff release amounts, which confirmed the flavor release stability and uniformity of IG under heating treatment.     

高氯酸化三邻菲啰啉合镍晶体结构研究

用Ni(ClO4)2合成了高氯酸阴离子和三邻菲啰啉合镍阳离子组成的盐晶体, 晶体结构由X射线衍射确定. 晶体属P21/n空间群, a=0.9388(2) nm, b=3.0139(5) nm, c=1.2974(2) nm, β=111.054(3)º, V=3.426(1) nm3. 采用hyperchem程序包的半经验方法ZINDO/1计算了该配合物的最优化结构, 原子电荷分布很好地佐证了晶体结构的配位环境.     

Zwei Mercuri‐Ammin‐Komplexe: [Hg(NH3)2][HgCl3]2 und [Hg(NH3)4](ClO4)2

Two Mercuric Ammoniates: [Hg(NH₃)₂][HgCl₃]₂ and [Hg(NH₃)₄](ClO₄)₂ [Hg(NH₃)₂][HgCl₃]₂ ( 1 ) is obtained by saturating an equimolar solution of HgCl₂ and NH₄Cl with Hg(NH₂)Cl at 75 °C. 1 crystallizes in the orthorhombic space group Pmna with a = 591.9(1) pm, b = 800.3(1) pm, c = 1243.3(4) pm, Z = 2. The structure consists of linear cations [Hg(NH₃)₂]²⁺ and T‐shaped anions [HgCl₃]^—. The coordination sphere of mercury is ?effectively”? completed to compressed hexagonal bipyramids and distorted octahedra, respectively. Single crystals of [Hg(NH₃)₄](ClO₄)₂ ( 2 ) are obtained by passing gaseous ammonia through a solution of mercuric perchlorate, while the solution was cooled to temperatures below 10 °C. 2 crystallizes in the monoclinic space group P2₁/c with a = 791.52(9) pm, b = 1084.3(2) pm, c = 1566.4(2) pm, β = 120.352(1)°, Z = 4. The structure consists of compressed [Hg(NH₃)₄]²⁺ tetrahedra and perchlorate anions. The packing of the heavy atoms Hg and Cl is analogous to the baddeleyite (α‐ZrO₂) type of structure.     

First characterization of the ammine-ammonium complex [(NH4(NH3)4)2(mu-NH3)2]2+ in the crystal structure of [NH4(NH3)4][B(C6H5)4].NH3 and the [NH4(NH3)4]+ complex in [NH4(NH3)4][Ca(NH3)7]As3S6.2NH3 and [NH4(NH3)4][Ba(NH3)8]As3S6.NH3

The compound [NH4(NH3)4][B(C6H5)4].NH3 (1) was prepared by the reaction of NaB(C(6)H(5))(4) with a proton-charged ion-exchange resin in liquid ammonia. [NH(4)(NH(3))(4)][Ca(NH(3))(7)]As(3)S(6).2NH(3) (2) and [NH4(NH3)4][Ba(NH3)8]As3S6.NH3 (3) were synthesized by reduction of As(4)S(4) with Ca and Ba in liquid ammonia. All ammoniates were characterized by low-temperature single-crystal X-ray structure analysis. They were found to contain the ammine-ammonium complex with the maximal possible number of coordinating ammonia molecules, the [NH4(NH3)4]+ ion. 1 contains a special dimer, the [(NH4(NH3)4)2(mu-NH3)2]2+ ion, which is formed by two[NH4(NH3)4]+ ions linked by two ammonia molecules. The H(3)N-H...N hydrogen bonds in all three compounds range from 1.82 to 2.20 A (DHA = Donor-H...Acceptor angles: 156-178 degrees). In 2 and 3, additional H(2)N-H...S bonds to the thioanions are observed, ranging between 2.49 and 3.00 A (DHA angles: 120-175 degrees). Two parallel phenyl rings of the [B(C(6)H(5))(4)](-) anion in 1 form a pi...pi hydrogen bond (C...C distance, 3.38 A; DHA angles, 82 degrees), leading to a dimeric [B(C6H5)4]2(2-) ion.     

DSC study of the phase transitions in [Ni(D2O)6](ClO4)2 and [Ni(H2O)6](ClO4)2

DSC measurements were carried out for [Ni(H₂O)₆](ClO₄)₂ (sampleH) and [Ni(D₂O)₆](ClO₄)₂ (sampleD) in the temperature range 300–380 K. For both compounds two anomalies on the DSC curves were detected. The results for sampleH are compared to those previously obtained using adiabatic calorimetry method. For both compounds studied in this work the high-temperature transition appears at the same temperature while the low-temperature one is shifted towards higher temperatures in sampleD. Disorder connected with H₂O or D₂O groups is suggested in the intermediate phase between the low- and high-temperature transitions.     

Crystal Structure of Ni(NH3)Cl2 and Ni(NH3)Br2

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)Br₂: a = 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 [NiX_3/3X_2/2(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.     

Isotype Strukturen einiger Hexaamminmetall(II)-halogenide von 3d-Metallen: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 und [Ni(NH3)6]Cl2

The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH₃)₆]I₂, [Cr(NH₃)₆]I₂, [Mn(NH₃)₆]Cl₂, [Fe(NH₃)₆]Cl₂, [Fe(NH₃)₆]Br₂, [Co(NH₃)₆]Br₂ and [Ni(NH₃)₆]Cl₂ Crystals of yellow [V(NH₃)₆]I₂ and green [Cr(NH₃)₆]I₂ were obtained by the reaction of VI₂ and CrI₂ with liquid ammonia at room temperature. Colourless crystals of [Mn(NH₃)₆]Cl₂ were obtained from Mn and NH₄Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH₃)₆]Cl₂ and [Fe(NH₃)₆]Br₂ were obtained by the reaction of FeCl₂ and FeBr₂ with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH₃)₆]Br₂ were obtained from [Co₂(NH₂)₃(NH₃)₆]Br₃. Purple crystals of [Ni(NH₃)₆]Cl₂ were obtained by the reaction of NiCl₂ · 6H₂O and NH₄Cl with aqueous NH₃ solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K₂[PtCl₆] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.