Intercalation of α,ω-Alkanediamines in Layered Aluminium Dihydrogen Triphosphate Dihydrate

Intercalation of ,-alkanediamines, NH₂(CH₂) _n NH₂ (n = 3–10), into layered aluminium dihydrogen triphosphate dihydrate, AlH₂(P₃(O₁₀... 2H₂O, was investigated by XRD, DTA-TG, elemental analysis, and solid-state ³¹P, ¹³C and ²⁷Al NMR. ,-Alkanediamines are intercalated to form a monomolecular layer in the interlayer region, in which the alkanediamines incline at 57 ± 5° to the phosphate layers, whereas n-alkylamines form a bilayer structure with the same inclination angle. Two amino groups in an ,-alkanediamine molecule bridge the layered sheets of phosphates.     

铽配合物Tb(PMIP)3(PhCA)的合成及阴离子识别研究

本文设计合成了稀土铽配合物Tb(PMW)3(PhCA)作为阴离子试剂,利用荧光光谱考察了其与F-、Cl-、Br-、I-、ClO4-、NO3-、AcO-和H2PO-4等阴离子的作用.研究结果表明:不同阴离子的加入能够调控,Tb(PMIP)3(PhCA)的发光行为,当一定量的氟离子(醋酸根离子、磷酸二氢根离子)加入到Tb(PMIP)3(PhCA)的乙腈溶液中后,荧光发射增强;过量的氟离子(醋酸根离子、磷酸二氢根离子)加入后则使其荧光淬灭.而在乙腈和水混合溶液中,Tb(PMIP)3(PhCA)则能选择性识别氟离子和磷酸二氢根离子.     

Reversible Dihydrogen Activation and Hydride Transfer by a Uranium Nitride Complex

Cleavage of dihydrogen is an important step in the industrial and enzymatic transformation of N₂ into ammonia. The reversible cleavage of dihydrogen was achieved under mild conditions (room temperature and 1 atmosphere of H₂) by the molecular uranium nitride complex, [Cs{U(OSi(O^tBu)₃)₃}₂(μ‐N)] 1, leading to a rare hydride–imide bridged diuranium(IV) complex, [Cs{U(OSi(O^tBu)₃)₃}₂(μ‐H)(μ‐NH)], 2 that slowly releases H₂ under vacuum. This complex is highly reactive and quickly transfers hydride to acetonitrile and carbon dioxide at room temperature, affording the ketimide‐ and formate‐bridged U^IV species [Cs{U(OSi(O^tBu)₃)₃}₂(μ‐NH)(μ‐CH₃CHN)], 3 and [Cs{U(OSi(O^tBu)₃)₃}₂(μ‐HCOO)(μ‐NHCOO)], 4 .     

Structural, thermal and dielectric studies on a new solution grown 4-dimethylaminopyridinium dihydrogen phosphate crystal

Single crystals of 4-dimethylaminopyridinium dihydrogen phosphate (DMAPDP) (C₇H₁₃N₂PO₄) were grown by the solvent evaporation method. The three-dimensional structure was solved by the single-crystal X-ray diffraction method which belongs to triclinic crystal system and the molecular arrangements in the crystal were studied. The thermal behaviour was investigated using differential scanning calorimetry (DSC) and no phase transition was identified in the temperature region −150 to 230 °C. The thermal parameters—thermal diffusivity (), thermal effusivity (e), thermal conductivity (K) and heat capacity (C_p) of DMAPDP were measured by an improved photopyroelectric technique at room temperature. Dielectric constant and dielectric loss of the grown crystal were evaluated for the frequency range 1–200 KHz in the temperature region 28–135 °C. The Vicker's hardness was measured as 42.2 for a load of 98.07 mN. The laser induced surface damage threshold of DMAPDP crystal was found to be 4.8 GW/cm² with nanosecond Nd:YAG laser.     

How can the metal affect the proton transfer to the dihydrides [{P(CH2CH2PPh2)3}MH2] (M = Fe,Ru, Os)? A low-temperature electronic spectroscopy study

According to low-temperature UV-Vis spectroscopy data, the two-step protonation of iron subgroup metal hydrides [{P(CH₂CH₂PPh₂)₃}MH₂] (M = Fe, Ru, Os) with p-nitrophenol includes the formation of ion pairs stabilized by a hydrogen bond between the cationic dihydrogen complex and the phenolate anion. The trend of the extent of proton transfer appeared to be aperiodic, FeI OsI < RuI, in contrast to the previously obtained sequence of the proton-acceptor capacity of the hydride ligand, which increases down the group.     

Do Secondary Electrostatic Interactions Influence Multiple Dihydrogen Bonds? AA−DD Array on an Amine-Borane Aza-Coronand: Theoretical Studies and Synthesis

Hydrogen bond plays a key role in a wide range of inorganic, organic, as well as biological systems. The understanding on how the chemical environment can affect this kind of interaction is crucial to predict its binding strength and consequently the robustness and the dynamic properties of many supramolecular systems. In this paper a new donor-acceptor complex was synthesized and characterized by SCXRD, showing for the first time in an organic system an AA−DD pattern of a particular hydrogen interaction, called dihydrogen bond. Over 250 functionals were computationally evaluated to select the best method to reproduce the binding interaction geometry of this new pattern. Moreover, a new vector force model was used to split the contribution of primary and secondary electrostatic interactions (SEIs), in order to evaluate how the latter one can modify the binding strength of this unusual hydrogen-hydrogen interaction.     

Metal-like Ductility in Organic Plastic Crystals: Role of Molecular Shape and Dihydrogen Bonding Interactions in Aminoboranes

Ductility is a common phenomenon in many metals but is difficult to achieve in molecular crystals. Organic crystals bend plastically on one or two face-specific directions but fracture when stressed in any other arbitrary directions. An exceptional metal-like ductility and malleability in the isomorphous crystals of two globular molecules, BH₃NMe₃ and BF₃NMe₃, is reported, with characteristic tensile stretching, compression, twisting, and thinning. The mechanically deformed samples, which transition to lower symmetry phases, retain good long-range order amenable to structure determination by single-crystal X-ray diffraction. Molecules in these high-symmetry crystals interact through electrostatic forces (B⁻−N⁺) to form columnar structures with multiple slip planes and weak dispersive forces between columns. On the other hand, the limited number of facile slip planes and strong dihydrogen bonding in BH₃NHMe₂ negates ductility. Our study has implications for the design of soft ferroelectrics, solid electrolytes, barocalorics, and soft robotics.     

疏水球状碳酸钙的制备、表征及对聚丙烯力学性能的影响

以十二碳醇磷酸酯(DDP)为改性剂, 采用碳化法制备了分散性良好的球状碳酸钙粒子. 通过FESEM, XRD, FTIR及活化度和接触角测试对产物进行了表征. XRD分析结果表明, 随着DDP添加量的增加, 所得CaCO3由方解石型向文石型转变. FTIR结果表明, 改性剂与碳酸钙表面是以化学键合和物理吸附方式相结合. 当DDP含量达到2%时, 接触角为120.43°, 活化度达到99%, 碳酸钙粒子由亲水性转变为完全疏水性. 考察了反应温度和DDP含量对产物形貌与结晶行为的影响, 并对改性机理进行了初步探讨. 将产品填充到聚丙烯(PP)中, 测定了PP的力学性能.