Molecular geometries of H2S···ICF3 and H2O···ICF3 characterised by broadband rotational spectroscopy

The rotational spectra of three isotopologues of H(2)S···ICF(3) and four isotopologues of H(2)O···ICF(3) are measured from 7-18 GHz by chirped-pulse Fourier transform microwave spectroscopy. The rotational constant, B(0), centrifugal distortion constants, D(J) and D(JK), and nuclear quadrupole coupling constant of (127)I, χ(aa)(I), are precisely determined for H(2)S···ICF(3) and H(2)O···ICF(3) by fitting observed transitions to the Hamiltonians appropriate to symmetric tops. The measured rotational constants allow determination of the molecular geometries. The C(2) axis of H(2)O/H(2)S intersects the C(3) axis of the CF(3)I sub-unit at the oxygen atom. The lengths of halogen bonds identified between iodine and sulphur, r(S···I), and iodine and oxygen, r(O···I), are determined to be 3.5589(2) ? and 3.0517(18) ? respectively. The angle, φ, between the local C(2) axis of the H(2)S/H(2)O sub-unit and the C(3) axis of CF(3)I is found to be 93.7(2)° in H(2)S···ICF(3) and 34.4(20)° in H(2)O···ICF(3). The observed symmetric top spectra imply nearly free internal rotation of the C(2) axis of the hydrogen sulphide/water unit about the C(3) axis of CF(3)I in each of these complexes. Additional transitions of H(2)(16)O···ICF(3), D(2)(16)O···ICF(3) and H(2)(18)O···ICF(3) can be assigned only using asymmetric top Hamiltonians, suggesting that the effective rigid-rotor fits employed do not completely represent the internal dynamics of H(2)O···ICF(3).     

ZnSO4·CO(NH2)2·2H2O和MgCl2·NH4Cl·6H2O的热分解动力学研究

采用TG-DSC研究了ZnSO4·CO(NH2)2·2H2O和MgCl2·NH4Cl·6H2O的热分解反应,并对其中的脱水过程及部分分解过程进行了动力学计算,由Fridman、Ozawa-Flynn-Wall、ASTME698三种方法得出峰温时的活化能值与指前因子值,通过优化选择出了热分解过程最佳机理函数.     

Theoretical studies on reactions of the stabilized H2COO with HO2 and the HO2···H2O complex

The reactions of H(2)COO with HO(2) and the HO(2)···H(2)O complex are studied by employing the high-level quantum chemical calculations with B3LYP and CCSD(T) theoretical methods, the conventional transition-state theory (CTST), and the Rice-Ramsperger-Kassel-Marcus (RRKM) with Eckart tunneling correction. The calculated results show that the proton transfer plus the addition reaction channel (TS1A) is preferable for the reaction of H(2)COO with HO(2) because the barriers are -10.8 and 1.6 kcal/mol relative to the free reactants and the prereactive complex, respectively, at the CCSD(T)/6-311++G(3df,2p)//B3LYP/6-311++G(d,p) level of theory. Furthermore, the rate constant via TS1A (2.23 × 10(-10) cm(3) molecule(-1) s(-1)) combined with the concentrations of the species in the atmosphere demonstrates that the HO(2) radical would be the dominant sink of H(2)COO in some areas, where the concentration of water is less than 10(17) molecules cm(-3). In addition, although the single water molecule would lower the activated barrier of TS1A from 1.0 to 0.1 kcal/mol with respect to the respective complexes, the rate constant is lower than that of the reaction of HO(2) with H(2)COO.     

Concerted halogen and hydrogen bonding in [RuI2(H2dcbpy)(CO)2]···I2···(CH3OH)···I2···[RuI2(H2dcbpy)(CO)2

A new type of concerted halogen bond-hydrogen bond interaction was found in the solid state structure of [RuI(2)(H(2)dcbpy)(CO)(2)]···I(2)···(MeOH)···I(2)···[RuI(2)(H(2)dcbpy)(CO)(2)]. The iodine atoms of the two I(2) molecules interact simultaneously with each other and with the OH group of methanol of crystallization. The interaction was characterized by single crystal X-ray measurements and by computational charge density analysis based on DFT calculations.     

包结物[H2(teta)]2+·2Cl-·3H2O的合成与结构研究

大环化合物在生命和材料科学中很重要[1,2]。大环四胺配体5,7,7,12,14,14 六甲基 1,4,8,11 四氮杂环十四烷(teta)近年来引起了广泛关注[3,4]。我们合成了化合物[H2(teta)]2+·2Cl-·3H2O,测定了晶体结构。1　实验部分1.1　[H2(teta)]2+·2Cl-·3H2O的合成[5]将5mL0 4mmolHCl水溶液缓慢加入teta·2H2O(0 0641g,0 2mmol)的5mL甲醇溶液。连续搅拌半小时后过滤,无色滤液在室温下放置两天后长出淡黄色块状晶体。元素分析(计算值)%:C,47 58(46 71);H,10 53(10 78);N,13 68(13 62).IR(cm 1):3331(vs),3231(s),3186(vs),2973(s),2876(s)…     

Syntheses and structures of p-HOOCC6F4COOH · H2O (H2L · H2O) and luminescent coordination polymers [Tb2(H2O)4(L)3 · 2H2O] n and Tb2(Phen)2(L)3 · 2H2O

Compounds p-HOOCC₆F₄COOH · H₂O (H₂L · H₂O), [Tb₂(H₂O)₄(L)₃ · 2H₂O] _n (I), and Tb₂(Phen)₂(L)₃ · 2H₂O (II) are synthesized. According to the X-ray structure analysis data, the crystal structure of H₂L · H₂O is built of centrosymmetric molecules H₂L and molecules of water of crystallization. The crystal structure of compound I is built of layers of coordination 2D polymer [Tb₂(H₂O)₄(L)₃] _n and molecules of water of crystallization. The ligands are the L^2? anions performing both the tetradentate bridging and pentadentate bridging-chelating functions. The coordination polyhedron TbO₉ is a distorted three-capped trigonal prism. Acid H₂L manifests photoluminescence in the UV region (??_max = 368 nm). Compounds I and II have the green luminescence characteristic of the Tb³⁺ ions, and the band with ??_max = 545 nm (transition ⁵ D ₄?? ⁷ F ₅) is maximum in intensity. The photoluminescence intensity of compound II is higher than that for compound I.     

Structure of (C3H5NH3)2H2P2O7·H2O

The bis(cyclopropylammonium)dihydrogenodiphosphate monohydrate is a new diphosphate associated with the organic molecule C₃H₅NH₂. We report the chemical preparation and the crystal structure of this organic cation diphosphate. (C₃H₅NH₃)₂H₂P₂O₇.H₂O is orthorhombic (S.G. : P2₁2₁2₁), with Z = 4 and the following unit-cell parameters : a = 4.828(1) Å, b = 11.011(1) Å, c = 25.645(2) Å. The P₂O₇ groups and H₂O water molecules form a succession of bidimensional layers perpendicular to the c axis. The organic cations ensure the three-dimensional cohesion by NH-O hydrogen bonds.     

2MgO·2B2O3·MgCl2·14H2O-MgCl2-H2O体系30℃相平衡

用相平衡方法研究2MgO@2B2O3@MgCl2@14H2O在30℃不同质量分数MgCl2水溶液中的溶解转化产物及其溶解度.结果表明,该复盐在MgCl2的质量分数0～2%浓度范围,发生不同步溶解并转化为多水硼镁石(2MgO@3B2O3@15H2O);在MgCl2的质量分数2%～13.8%浓度范围,转化为柱硼镁石(MgO@B2O3@3H2O),这一结果比文献报导的该硼酸盐的形成温度低了13℃,为盐湖硼酸镁矿物柱硼镁石形成的解释提供了物理化学依据;而在MgCl2质量分数大于13.8%时,同步溶解,不发生转化.提出了溶解相转化反应机理.     

·C2H3+O2→HC·O+H2CO 的密度泛函理论研究

应用密度泛函理论研究了@C2H3+O2→HC@O+H2CO的反应机理.在DFT(B3LYP/6-31G*)水平上对反应过程中所有反应物、中间体、过渡态和产物的几何构型进行优化,通过频率振动分析确认中间体和过渡态.计算IRC反应路径的能量,分析了中间体的异构化过程和各主要原子的自旋密度.     

用醇还原VOPO4·2H2O制备的VOHPO4·0.5H2O的择优取向性能

 研究了用醇还原VOPO4·2H2O制备的VOHPO4·0．5H2O的晶面择优\r\n取向现象及其在正丁烷和空气混合气体中活化后,产物（VO）2P2O7的\r\n晶面择优暴露对正丁烷氧化制顺酐性能的影响．以伯醇还原VOPO4·2H\r\n2O制备的VOHPO4·0．5H2O晶体,晶面择优取向于（220）面,晶型为玫\r\n瑰状或扭曲的片状聚集体;活化后的产物仅含（VO）2P2O7相,其（02\r\n0）晶面择优暴露．以仲醇还原VOPO4·2H2O制备的VOHPO4·0．5H2O晶\r\n体,晶面择优取向于（001）面,晶型为平板片状体;活化后的产物由\r\n（VO）2P2O7,VOPO4和无定形相组成,其中（VO）2P2O7相含量低,其\r\n（020）晶面暴露少．由苄醇、环己醇和3－甲基－3庚醇还原VOPO4·2\r\nH2O制备的VOHPO4·0．5H2O的XRD谱与用仲醇制备的相似．用一般方法\r\n（V2O5／异丁醇／H3PO4）制备的VOHPO4·0．5H2O晶体不具有晶面择优\r\n取向性质,活化后得到的（VO）2P2O7的结晶度较低．由正辛醇还原VO\r\nPO4·2H2O制备的VOHPO4·0．5H2O经活化后,对正丁烷氧化制顺酐的催\r\n化性能优于用仲辛醇和一般方法制备的VOHPO4·0．5H2O．     

配合物Ni(HDPC)2·3H2O和Cu(DPC)(H2DPC)·2H2O的制备及反应热动力学

吡啶-2,6-二甲酸(Pyridine-2,6-dicarboxylic acid,H 2DPC)是一个灵活多变的刚性配体,能提供N原子和O原子与过渡、非过渡和稀土金属离子鳌合形成稳定的配合物[1-3],与过渡金属离子形成的配合物在催化、磁性、发光和医药等方面具有潜在的应用价值[4-6].     

An analysis of the vibrational frequencies and amplitudes of the H5O+2 ion in H4SiW12O40·6H2O (TSA·6H2O) and H3PW12O40·6H2O (TPA·6H2O)

The infrared, Raman and inelastic neutron scattering (INS) spectra of TSA·6H₂O and TPA·6H₂O are in agreement with those expected for the presence of H₅O⁺₂ ions. Force fields for different assignment schemes are compared with the observed vibrational frequencies and the INS spectral profile. All but two schemes are eliminated. Whilst low-resolution INS spectroscopy cannot distinguish between these two schemes, the orientations of the vibrational ellipsoids for one scheme are in better agreement with those reported from low-temperature crystallographic studies of the H₅O⁺₂ ion.     

Thermochemical study of [Sm(C7H5O3)2·(C4H6NO2S)]·2H2O

The product from reaction of samarium chloride hexahydrate with salicylic acid and Thioproline, [Sm(C₇H₅O₃)₂·(C₄H₆NO₂S)]·2H₂O, was synthesized and characterized by IR, elemental analysis, molar conductance, and thermogravimetric analysis. The standard molar enthalpies of solution of [SmCl₃·6H₂O(s)], [2C₇H₆O₃(s)], [C₄H₇NO₂S(s)] and [Sm(C₇H₅O₃)₂·(C₄H₇NO₂S)·H₂O(s)] in a mixed solvent of absolute ethyl alcohol, dimethyl sulfoxide(DMSO) and 3 mol L^?1 HCl were determined by calorimetry to be Δ_s H _m ^Φ [SmCl₃ δ6H₂O (s), 298.15 K]= ?46.68±0.15 kJ mol^?1 Δ_s H _m ^Φ [2C₇H₆O₃ (s), 298.15 K]= 25.19±0.02 kJ mol^?1, Δ_s H _m ^Φ [C₄H₇NO₂S (s), 298.15 K]=16.20±0.17 kJ mol^?1 and Δ_s H _m ^Φ [Sm(C₇H₅O₃)₂·(C₄H₆NO₂S)]·2H₂O (s), 298.15 K]= ?81.24±0.67 kJ mol^?1. The enthalpy change of the reaction (1) $$ SmCl_3 \cdot 6H_2 O(s) + 2C_7 H_6 O_3 (s) + C_4 H_7 NO_2 S(s) = Sm(C_7 H_5 O_3 )_2 \cdot (C_4 H_6 NO_2 S) \cdot 2H_2 O(s) + 3HCl(g) + 4H_2 O(1) $$ was determined to be Δ_s H _m ^Φ =123.45±0.71 kJ mol^?1. From date in the literature, through Hess’ law, the standard molar enthalpy of formation of Sm(C₇H₅O₃)₂(C₄H₆NO₂S)δ2H₂O(s) was estimated to be Δ_s H _m ^Φ [Sm(C₇H₅O₃)₂·(C₄H₆NO₂S)]·2H₂O(s), 298.15 K]= ?2912.03±3.10 kJ mol^?1.     

[Ni(PMBPTSC)(H2PMBPTSC)]·C2H5OH·2H2O的合成、 结构和非等温热分解动力 学

报道了标题配合物[Ni(PMBPTSC)(H2PMBPTSC)]·C2H5OH·2H2O的制备,晶体结构及非等温热分解动力学,该晶体属单斜晶系,空间群Pn,a=1.0376(3)nm,b=1.1522(3)nm,c=1.7591(3)nm;β=90.75(2)°;V=2.1028(8)nm^3;Z=2,Dc=1.329g/cm^3;μ=0.614mm^-1;F(000)=880.根据TG-DTG曲线,运用Achar法与Coats-Redfer法对配合物第一步热分解反应进行了非等温热分解动力学研究,其机理为三维扩散机理,动力学方程为da/dt=Ae^-E/RT3/2(1-α)^2/3[1-(1-α)^1/3]^-1,动力学补偿效应表达式为lnA=0.307915E-1.20469.     

Mg(OH)2· 2MgSO4· 2H2O晶体的水热生长过程

对 MgSO4- NaOH- H2O四元交互体系在 160 ℃水热条件下 ,相同物料配比 ,不同反应时间的晶体生长过程进行了研究 ,得到 5Mg(OH)2@ MgSO4@ 2H2O(简称 MOS)晶须和 Mg(OH)2@ 2MgSO4@ 2H2O棒状晶体两种硫氧镁化合物 .通过化学分析、 X- ray粉末衍射、 FT- IR光谱和 SEM对反应产物进行了表征 .前者是该体系水热条件下介稳产物 ,而新的硫氧镁化合物 Mg(OH)2@ 2MgSO4@ 2H2O是该体系的稳定相.     

Synthesis and properties of tetraalkylammonium chlorides peroxosolvates (CH3)4NCI·H2O2 and (C2H5)4NCl·H2O2

Tetraalkylammonium chlorides peroxosolvates (CH₃)₄NCl·H₂O₂ and (C₂H₅)₄NCl·H₂O₂ were synthesized. The composition of the solvates was proved by chemical analysis; their X-ray patterns, IR spectra, and thermograms were obtained. The solubility of the solvates in water and their stability in aqueous solutions were investigated.     

Structure of the complex [trans-SnF4(H2O)2· (18-crown-6)· 2H2O]

The molecular and crystal structure of the title complex (I) obtained by addition of tin fluoride in a hydrofluoric acid solution to 18-crown-6 in methanol was investigated by X-ray structure analysis. The crystals are monoclinic, space group P2₁/n, a = 13.497(3), b = 7.806(2), c = 9.892(2) Å, β = 95.57(3)°, Z = 2 for C₁₂H₃₂F₄O₁₀Sn. In the polymer chain, the crown ether molecules alternate with the inorganic complexes [trans-SnF₄(H₂O)₂] and are linked to them by O-H...O type hydrogen bonds involving the intermediate water molecules. The weak C-H...F interactions bind the chains into the layers which are parallel to the xz plane.     

2MgO·2B2O3·MgCl2·14H2O-H2O体系在沸点温度的相转化研究

2MgO·2B2O3·MgCl2·14H2O(氯柱硼镁石)是从天然浓缩盐卤中得到的一种新硼酸镁盐[1].已报道过在实验室中模拟合成盐卤对该复盐的合成条件[2].为了探讨该复盐在盐湖沉积过程中的形成和转化条件,对其在10～60℃水中溶解及相转化动力学过程做过研究,其中10～50℃时的最终溶解转化产物是2MgO·3B2O3·15H2O(多水硼镁石)[3],60℃是MgO.B2O3.H2O(柱硼镁石)[4].