Beiträge zur Chemie des Phosphors. 239 [1]. Reaktion von Diphosphan(4) mit Diboran(6) und mit THF-Boran: Bildung von Diphosphan-boran,P2H4 · BH3, und Diphosphan-1,2-bis(boran), BH3 · P2H4 · BH3

Contributions to the Chemistry of Phosphorus. 239. On the Reaction of Diphosphane(4) with Diborane(6) and with THF-Borane: Formation of Diphosphane-borane, P₂H₄ · BH₃, and Diphosphane-1,2-bis(borane), BH₃ · P₂H₄ · BH₃ Diphosphane(4) always reacts with diborane(6) in the temperature range of ?118 to ?78°C, to furnish a mixture of diphosphane-borane, P₂H₄ · BH₃ ( 1 ), and diphosphane-1,2-bis(borane), BH₃ · P₂H₄ · BH₃ ( 2 ), in addition to small amounts of triphosphane-1,3-bis(borane), BH₃ · P₃H₅ · BH₃, and phosphane-borane, BH₃ · PH₃, irrespective of the molar ratios of the reactants employed. The formation of the 1 : 1 adduct P₂H₄ · B₂H₆ reported in the literature [4] could not be confirmed. The structures of compounds 1 and 2 were investigated by nuclear magnetic resonance spectroscopy which revealed the complete, homolytic cleavage of diborane(6). As a result of the bonding of one BH₃ group to diphosphane(4), the Lewis basicity of the other PH₂ group is markedly reduced. Similar mixtures of products are obtained when the borane adduct THF · BH₃ is employed in an analogous reaction. In the case of a 1 : 1 molar ratio of P₂H₄ : THF · BH₃ at ?78°C, the reaction furnishes compound 1 exclusively. This product can be isolated in the pure state and is found to be appreciably more stable than diphosphane(4).     

Reaktion von Diphosphan(4) mit flüssigem Ammoniak und mit Aminen – ein neuer Weg zu Polyphosphiden und Hydrogenpolyphosphiden

Contributions to the Chemistry of Phosphorus. 241. On the Reaction of Diphosphane(4) with Liquid Ammonia and with Amines – a New Route to Polyphosphides and Hydrogen Polyphosphides Diphosphane(4), P₂H₄, reacts with liquid ammonia in the temperature range –76 °C to –40 °C to furnish a mixture of the ammonium polyphosphides (NH₄)₂H₂P₁₄, (NH₄)₂P₁₆, (NH₄)₃P₁₉, and (NH₄)₃P₂₁, in addition to PH₃. The first intermediate product detectable by NMR spectroscopy is the bicyclic compound NH₄H₄P₇, which reacts further with P₂H₄ to afford the more phosphorus‐rich polycyclic phosphides. On removal of the ammonia the hydrogen polyphosphide (NH₄)₂H₂P₁₄ decomposes with formation of PH₃ and hydrogen‐free, more phosphorus‐rich polyphosphides. When the reaction of diphosphane(4) with liquid ammonia is performed in the presence of tetrahydrofuran the final products are the hydrogen polyphosphides NH₄H₄P₇ and NH₄H₅P₈ together with PH₃; the hydrogen‐rich, open‐chain heptaphosphide NH₄H₈P₇ has been identified as a precursor. An investigation of the behavior of diphosphane(4) towards amines using the primary amine ethylenediamine as an example at +10 °C in the absence of a solvent or in the presence of tetrahydrofuran resulted in the formation of a polyphosphide mixture consisting of (C₂H₄N₂H₅)₂P₁₆, (C₂H₄N₂H₅)₃P₂₁, and (C₂H₄N₂H₅)₃P₁₉ as well as some PH₃. No reaction occurred with the secondary and tertiary amines diethylamine and tetramethylethylenediamine (TMEDA), respectively, even at room temperature.     

Beiträge zur Chemie des Phosphors. 240 [1]. Zum reaktiven Verhalten von Diphosphan-boran,P2H4 · BH3

Contributions to the Chemistry of Phosphorus. 240. On the Reactive Behaviour of Diphosphane-borane, P₂H₄ · BH₃ Under mild temperature conditions, the thermal decomposition of diphosphane-borane ( 1 ) gives rise to the formation of phosphane-borane, PH₃ · BH₃, and triphosphane-2-borane, PH₂? PH(BH₃)? PH₂ ( 2 ). In the presence of diphosphane-1,2-bis(borane), triphosphane-1,3-bis(borane), BH₃? PH₂? PH? PH₂? BH₃ ( 3 ), is formed additionally. The thermolysis product at room temperature is a polymeric solid of varying composition which contains phosphorus, boron, and hydrogen. Compound 1 reacts with metalating agents such as n-BuLi, LiBH₄, and NaBH₄ to furnish the borane-trihydrogendiphosphide ion, [PH₂? PH? BH₃]^?, which immediately disproportionates to give the corresponding mono-and triphosphane derivatives. In the presence of an excess of THF-borane and in the case of a 1 : 1 molar ratio of 1 : NaBH₄, the disproportionation does not occur and the new diphosphide derivative sodium-1,1,2-tris(borane)-1,2,2-trihydrogendiphosphide, Na[(BH₃)₂PH? PH₂BH₃] ( 4 ) can be obtained. The action of additional NaBH₄ yields the diphosphide dianion with four coordinated BH₃ groups.     

Beiträge zur Chemie des Phosphors. 43. Gaschromatographische Trennung von Phosphanen

Monophosphane (PH₃), diphosphane (P₂H₄), and triphosphane-5 (P₃H₅) could be separated in mixtures by isothermal gas chromatography. On the basis of the experiences hereby obtained, further gas chromatographic separations were carried out with a programmed temperature mode. For the identification of the chromatographic peaks a mass spectrometer as a second detector was applied. In the temperature range from ?60°C to +60°C, it was possible for the first time to separate mixtures of diphosphane and higher phosphanes without any decomposition in the gas chromatographic column. Besides monophosphane and diphosphane, triphosphane-3 (P₃H₃), triphosphane-5 (P₃H₅), and tetraphosphane-6 (P₄H₆) could be eluated as undecomposed components. By this, a fundamental basis for the application of gas chromatography to the quantitative analysis of mixtures of phosphanes and to the development of a gas chromatographic method for the preparative isolation of individual higher phosphanes has been established.     

Beiträge zur Chemie des Phosphors. 237. Reaktion von Diphosphan(4) mit Peroxoverbindungen: Bildung von Phosphinophosphinsäure,H2PPH(O)OH,und Bis(phosphino)phosphinsäure, (H2P)2P(O)OH

Contributions to the Chemistry of Phosphorus. 237. On the Reaction of Diphosphane(4) with Peroxo Compounds: Formation of Phosphinophosphinic Acid, H₂PPH(O)OH, and Bis(phosphino)phosphinic Acid, (H₂P)₂P(O)OH Diphosphane(4) reacts with peroxo compounds such as hydrogen peroxide, tetraline hydroperoxide, trifluoroperoxyacetic acid, and cumene hydroperoxide (which is particularly suited for preparative work) at ?30°C to furnish phosphino-phosphinic acid, H₂PPH(O)OH ( 1 ), as the primary product. Compound 1 disproportionates to a major extent in statu nascendi to give phosphanes (above all PH₃) and monophosphorus acids of various oxidation states as well as some bis(phosphino)phosphinic acid, (H₂P)₂P(O)OH ( 2 ). The acids 1 and 2 can be trapped and stabilized as their triethylammonium salts. The structures of these salts have been determined by spectroscopic investigations.     

Earth Alkaline Tetrathiosquarates: Syntheses and Crystal Structures of MgC4S4 · 6 H2O and CaC4S4 · 4 H2O

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 C₄S₄^2? ions with almost undistorted D_4h 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, C₄S₄^2? 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.     

Beiträge zur Chemie des Phosphors. 235. Zur Darstellung größerer Mengen von Diphosphan(4) im Laboratorium

Contributions to the Chemistry of Phosphorus. 235. On the Preparation of Larger Amounts of Diphosphane(4) in the Laboratory The preparation of several hundred grammes of diphosphane(4) by hydrolysis of calcium phosphide in a semicontinuous process as well as the handling of larger amounts of this compound are reported. In comparison with earlier results [12], the yield has been raised by 37 percent with simultaneous increase of the accessible total amount. The white solid which is formed in the preparation and purification of diphosphane(4) is not, as was believed in earlier work [25, 8], triphosphane(5) or another, novel phosphorus hydride but is rather a clathrate compound of diphosphane(4) or the phosphanes P_nH_n+2 (n = 2–4) and water, respectively.     

Die Kristallstruktur des Bleicyclotetraphosphat-2-Hydrats,Pb2P4O12 · 2H2O

Crystal Structure of Lead Cyclotetraphosphate-2-Hydrate, Pb₂P₄O₁₂ · 2H₂O By heating of Pb₂P₄O₁₂ · 4 H₂O crystals at 100°C, Pb₂P₄O₁₂ · 2 H₂O is formed topotactically. The triclinic crystals are twinned on (010). Space group: P1 , unit cell: a = 8.02 ± 0.02, b = 10.58 ± 0.02, c = 7.53 ± 0.02 Å, α = 98.8 ± 0.2, β = 108.7 ± 0.2, γ = 82.6 ± 0.3°. The crystal structure was determined by Patterson and Fourier methods and refined by least-squares calculations. The structure consists of two crystallographically different P₄O₁₂^4? ring anions, point symmetry 1 , connected by Pb and hydrogen bonds. Both Pb atoms are coordinated by eight oxygen atoms. The polyhedra of either Pb are interconnected by common edges forming sheets and chains. Pb(1) is joined with four, Pb(2) with five P₄O₁₂^4? anions.     

Hydrate schwacher und starker Basen. XI. Die Kristallstrukturen von NaOH · 3,5H2O und NaOH · 7 H2O. Eine Präzisierung

Hydrates of Weak and Strong Bases. XI. The Crystal Structures of NaOH · 3,5H₂O and NaOH · 7 H₂O. A Refinement The crystal structures of the hydrates NaOH · 3,5 H₂O (space group P2₁/c, Z = 8 formula units per unit cell; lattice parameters: a = 6.481, b = 12.460, c = 11.681 Å, β = 104.12° at ?100°C) and NaOH · 7 H₂O (P2₁/c, Z = 4; a = 7.344, b = 16.356, c = 6.897 Å, β = 92.91° at ?150°C) have been redetermined using MoKα diffractometer data. The obtained refinement of the structures, including the localization also of the H atoms for the first time, has led to new findings with respect to the H bonds. In particular, in both hydrates there is one such interaction of the rare type OH^? …? OH₂, from an OH^? ion to an H₂O molecule, i. e. with the OH^? ion as the proton donor.     

Chemie polyfunktioneller Moleküle. 119 [1] Tetracarbonyl-dicobalt-tetrahedran-Komplexe mit den Liganden Bis(diphenyl-phosphanyl)amin, 2-Butin-1,4-diol und tert-Butylphosphaacetylen — Kristallstrukturanalyse des Phosphaalkin-Derivats

Chemistry of Polyfunctional Molecules. 119 [1]. Tetracarbonyl-dicobalt-tetrahedrane Complexes with the Ligands Bis(diphenylphosphanyl)-amine, 2-Butin-1,4-diol, and tert.-Butylphosphaacetylene — Crystal Structure of the Phosphaalkyne Derivative Co₂(μ-CO)₂(CO)₄(μ-Ph₂P? NH? PPh₂—P,P′) · 1/2C₆H₅CH₃ ( 4 · 1/2C₆H₅CH₃) reacts with 2-butine-1,4-diol, HOCH₂? C?C? CH₂OH ( 5 ), to the dark-red tetrahedrane complex Co₂(CO)₄(μ-η²,η²-HOCH₂? C?C? CH₂OH? C², C³) · (μ-Ph₂P? NH? PPh₂? P,P′) · THF (6 · THF). With t-butyl-phosphaacetylene, tBu? C?P ( 7 ), 4 · THF forms Co₂(CO)₄(μ-η²,η²-tBu? C?P)(μ-Ph₂P? NH? PPh₂? P,P′) ( 8 ), which also belongs to the tetrahydrane type. The compounds were characterized by their mass, IR, ³¹P{¹H} NMR, ¹³C{¹H} NMR, and¹H NMR spectra. Crystals suitable for X-ray structure analyses have been obtained for 8 from dioxane. The dark red blocks crystallize in the monoclinic P2₁/c space group with the lattice constants a = 1404,1(5), b = 1330,0(7), c = 2578,8(10)pm; β = 90,82(3)°.     

氢过碘酸）合银（III）配离子氧化L-脯氨酸的反应动力学及机理

L-脯氨酸独有的亚胺基使其在生物医药领域具有许多独特的功能,并广泛用作不对称有机化合物合成的有效催化剂。本文在碱性介质中研究了二（氢过碘酸）合银（III）配离子氧化 L-脯氨酸的反应。经质谱鉴定,脯氨酸氧化后的产物为脯氨酸脱羧生成的 γ-氨基丁酸盐;氧化反应对脯氨酸及Ag(III) 均为一级;二级速率常数 k′ 随 [IO₄^-] 浓度增加而减小,而与 [OHˉ] 的浓度几乎无关;推测反应机理应包括 [Ag(HIO₆)₂]^5-与 [Ag(HIO₆)(H₂O)(OH)]^2-之间的前期平衡,两种Ag（III）配离子均作为反应的活性组分,在速控步被完全去质子化的脯氨酸平行地还原,两速控步对应的活化参数为： k₁ (25 ^oC)＝1.87±0.04（mol·L^-1)^-1s^-1,∆ H₁^≠＝45±4 kJ · mol^-1, ∆ S₁^≠＝-90±13 J· K^-1·mol^-1 and k₂ (25 ^oC) ＝3.2±0.5（mol·L^-1)^-1s^-1, ∆ H₂^≠＝34±2 kJ · mol^-1, ∆ S₂^≠＝-122 ±10 J· K^-1·mol^-1。本文第一次发现 [Ag(HIO₆)₂]^5-配离子也具有氧化反应活性。     

New Hexachalcogeno–Hypodiphosphates of the Alkali Metals: Synthesis,Crystal Structure and Vibrational Spectra of the Hexathiodiphosphate(IV) Hydrates K4[P2S6] · 4 H2O,Rb4[P2S6] · 6 H2O,and Cs4[P2S6] · 6 H2O

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.     

Die Polytherme des Quinären Systems Na+, K+, Mg2+/Cl−, SO//H2O im Bereich von +25° bis −10°C

Polythermal Curves of the Quinary System Na⁺, K⁺, Mg²⁺/Cl^?, SO//H₂O in Range between +25°C and ?10°C Proceeding from the 0°C, ?5°C and ?10°C isothermal curves of the quinary system Na⁺, K⁺, Mg²⁺/C1^?, SO//H₂O with saturation at NaCl, KCl, and carnallite, respectively, the polythermal curve is represented between 25°C and ?10°C. Within the new defined range of the polythermal curve the invariant five-salt-paragenesis NaCI, KCI, Glauber's salt (Na₂SO₄ · 10 H₂O), bitter salt (MgSO₄ · 7 H₂O), Schoenite (K₂SO₄ · MgSO₄ · 6 H₂O) can be found at ?7,2°C. It represents also the lowest temperature of formation of Schoenite in this system. It was necessary, moreover, to reconsider further univariant and invariant equilibrium solutions in the range between 25° and 0°C.     

Zur Bedeutung von V2O3(OH)4(g) für den chemischen Transport von V2O5(s) in Anwesenheit von Wasser. Nachweis des Gasteilchens,thermodynamische Daten und Modellrechnungen

V₂O₃(OH)₄(g), Proof of Existence, Thermochemical Characterization, and Chemical Vapor Transport Calculations for V₂O₅(s) in the Presence of Water By use of the Knudsen-cell mass spectrometry the existence of V₂O₃(OH)₄(g) is shown. For the molecules V₂O₃(OH)₄(g), V₄O₁₀(g), and V₄O₈(g) thermodynamic properties were calculated by known Literatur data. The influence of V₂O₃(OH)₄(g) for chemical vapor transport reactions of V₂O₅(s) with water ist discussed. Δ_BH°(V₂O₃(OH)₄(g), 298) = –1920 kJ · mol^–1 and S°(V₂O₃(OH)₄(g), 298) = 557 J · K^–1 · mol^–1, Δ_BH°(V₄O₁₀(g), 298) = –2865,6 kJ · mol^–1 and S°(V₄O₁₀(g), 298) = 323.7 J · K^–1 · mol^–1, Δ_BH°(V₄O₈(g), 298) = –2465 kJ · mol^–1 and S°(V₄O₈(g), 298) = 360 J · K^–1 · mol^–1.     

Calculation of Some Thermodynamic Properties and Detonation Parameters of 1‐Ethyl‐3‐Methyl‐H‐Imidazolium Perchlorate, [Emim][ClO4], on the Basis of CBS‐4M and CHEETAH Computations Supplemented by VBT Estimates

This paper estimates some thermochemical (in kcal mol^–1) and detonation parameters for the ionic liquid, [emim][ClO₄] and its associated solid in view of its investigation as an energetic material. The thermochemical values estimated, employing CBS‐4M computational methodology and volume‐based thermodynamics (VBT) include: lattice energy, U_POT([emim][ClO₄]) ≈? 123 ± 16 kcal · mol^–1; enthalpy of formation of the gaseous cation, Δ_fH°([emim]⁺, g) = 144.2 kcal · mol^–1 and anion, Δ_fH°([ClO₄]^–, g) = –66.1 kcal · mol^–1; the enthalpy of formation of the solid salt, Δ_fH°([emim][ClO₄],s) ≈? –55 ± 16 kcal · mol^–1 and for the associated ionic liquid, Δ_fH^o([emim][ClO₄],l) = –52 ± 16 kcal · mol^–1 as well as the corresponding Gibbs energy terms: Δ_fG°([emim][ClO₄],s) ≈? +29 ± 16 kcal · mol^–1 and Δ_fG^o([emim][ClO₄],l) = +24 ± 16 kcal · mol^–1 and the associated standard absolute entropies, of the solid [emim][ClO₄], S°₂₉₈([emim][ClO₄],s) = 83 ± 4 cal · K^–1 · mol^–1. The following combustion and detonation parameters are assigned to [emim][ClO₄] in its (ionic) liquid form: specific impulse (I_sp) = 228 s (monopropellant), detonation velocity (V_oD) = 5466 m · s^–1, detonation pressure (p_C–J) = 99 kbar, explosion temperature (T_ex) = 2842 K.     

Die Kristallstrukturen von [Cu2Cl2(AA · H+)2](NO3)2 und [AA · H+]Pikr− (AA · H+ = Allylammonium; Pikr− = Pikrat)

The Crystal Structures of [Cu₂Cl₂(AA · H⁺)₂](NO₃)₂ and [AA · H⁺]Picr^? (AA · H⁺ = Allylammonium; Picr^? = Picrat) By an alternating current electro synthesis the crystal-line π-complex [Cu₂Cl₂(AA · H⁺)₂](NO₃)₂ has been obtained from CuCl₂ · 2H₂O, allylamine (AA), and HNO₃ in ethanolic solution. X-ray structure analysis revealed that the compound crystallized in the monoclinic system, space group P2₁/a, a = 7.229(3), b = 7.824(3), c = 26.098(6) Å, γ = 94.46(5)°, Z = 4, R = 0.025 for 2 023 reflections. The crystal structure is built up of Cu_nCl_n chains which are connected by π-bonding bidentate AA · H⁺ …? ON(O)O …? H⁺ · AA units. For comparision with the above complex the structure of [AA · H⁺]Picr^? (Picr^? = picrate anion) is also reported.     

Über Chalkogenolate. 93. Untersuchungen über Trithioallophansäure 2. Darstellung und Eigenschaften der freien Säure [1]

On Chalcogenolates. 93. Studies on Trithioallophanic Acid 2. Preparation and Properties of the Free Acid Yellow trithioallophanic acid H₂N? CS? NH? CS(SH) has been prepared by reaction between a suspension of K[S₂C? NH? CS? NH₂] in diethyl ether and a solution of HCl in (C₂H₅)₂O at ?15°C; the ether was distilled off at ?15°C in vacuo. The compound has been characterized by means of infrared spectra, electron absorption, ¹H-NMR spectra, and mass spectra. The dissociation constant of trithioallophanic acid in water is K_a = (1,41 ± 0,08) · 10^?2 at 20°C.     

Thermochemistry on the Complex of Erbium Perchlorate with L-α-Glutamic Acid [Er2（L-Glu）2（H2O）6]（ClO4）4·6H2O（s）

A coordination compound of erbium perchlorate with L-α-glutamic acid, [Er2（Glu）2（H2O）6]（ClO4）4·6H2O（s）, was synthesized. By chemical analysis, elemental analysis, FTIR, TG/DTG, and comparison with relevant literatures, its chemical composition and structure were established. The mechanism of thermal decomposition of the complex was deduced on the basis of the TG/DTG analysis. Low-temperature heat capacities were measured by a precision automated adiabatic calorimeter from 78 to 318 K. An endothermic peak in the heat capacity curve was observed over the temperature region of 290-318 K, which was ascribed to a solid-to-solid phase transition. The temperature Ttrans, the enthalpy △transHm and the entropy △transSm of the phase transition for the compound were determined to be： （308.73±0.45） K, （10.49±0.05） kJ·mol^-1 and （33.9±0.2） J·K^-1·mol^-1. Polynomial equation of heat capacities as a function of the temperature in the region of 78-290 K was fitted by the least square method. Standard molar enthalpies of dissolution of the mixture [2ErCl3·6H2O（s）＋2L-Glu（s）＋6NaClO4·H2O（s）] and the mixture {[Er2（Glu）2（H2O）6]（ClO4）4·6H2O（s）＋6NaCl（s）} in 100 mL of 2 mol·dm^-3 HClO4 as calorimetric solvent, and {2HClO4（1）} in the solution A＇ at T=298.15 K were measured to be, △dHm,1=（31.552±0.026） kJ·mol^-1, △dHm,2 = （41.302±0.034） kJ·mol^-1, and △dHm,3 = （ 14.986 ± 0.064） kJ·mol^-1, respectively. In accordance with Hess law, the standard molar enthalpy of formation of the complex was determined as △fHm-=-（7551.0±2.4） kJ·mol^-1 by using an isoperibol solution-reaction calorimeter and designing a thermochemical cycle.     

Complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with 4-chloro-2-methoxybenzoic acid anion

The complexes of 4-chloro-2-methoxybenzoic acid anion with Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺ were obtained as polycrystalline solids with general formula M(C₈H₆ClO₃)₂·nH₂O and colours typical for M(II) ions (Mn – slightly pink, Co – pink, Ni – slightly green, Cu – turquoise and Zn – white). The results of elemental, thermal and spectral analyses suggest that compounds of Mn(II), Cu(II) and Zn(II) are tetrahydrates whereas those of Co(II) and Ni(II) are pentahydrates. The carboxylate groups in these complexes are monodentate. The hydrates of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) heated in air to 1273 K are dehydrated in one step in the range of 323–411 K and form anhydrous salts which next in the range of 433–1212 K are decomposed to the following oxides: Mn₃O₄, CoO, NiO and ZnO. The final products of decomposition of Cu(II) complex are CuO and Cu. The solubility value in water at 293 K for all complexes is in the order of 10^–3 mol dm^–3. The plots of χ_M vs. temperature of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II) follow the Curie–Weiss law. The magnetic moment values of Mn²⁺, Co²⁺, Ni²⁺ and Cu²⁺ ions in these complexes were determined in the range of 76−303 K and they change from: 5.88–6.04 μ_B for Mn(C₈H₆ClO₃)₂·4H₂O, 3.96–4.75 μ_B for Co(C₈H₆ClO₃)₂·5H₂O, 2.32–3.02 μ_B for Ni(C₈H₆ClO₃)₂·5H₂O and 1.77–1.94 μ_B for Cu(C₈H₆ClO₃)₂·4H₂O.     

对氨基苯甲酸热力学性质的量热和热分析研究

在80～400 K温区,用高精度全自动绝热量热仪测定了对氨基苯甲酸摩尔热容,得到摩尔热容随温度的变化的关系式为：