Orthorhombic 3-LiV2O5 as Cathode Materials in Lithium Ion Batteries： Synthesis and Property

The rod-like and bundle-like v-LiV205 were synthesized via a simple solvothermal process- ing. The rod-like 7-LiV205 with diameter of 500-800 nm and the bundle-like architectures are composed of several of order-attached rods with diameter of 100-600 nm. ＂y-LiV205 were synthesized using LiOH.H20, NH4VO3, HNO3, C2H5OH without and with PVP as raw materials. At the same time, the actual formation mechanism of Y-LiV205 was also investigated. As the cathode materials for lithium ion batteries, the bundle-like Y-LiV205 prepared with PVP delivers a better electrochemical performance, which has an initial dis charge capacity of 269.3 mAh/g at a current density of 30 mA/g and is still able to achieve 228 mAh/g after the 20th cycle. The good electrochemical properties of the as-synthesized Y-LiV205 coupled with the simple, relatively low temperature, and low cost of the prepara tion method may make this material a promising candidate as a cathode material for lithium ion batteries.     

Synthesis,Structure Characterization and Optical Properties of β Lithium Zinc Phosphate

β-LiZnPO_4 single crystal was successfully synthesized via hydrothermal method. It crystallizes in the trigonal space group R3 with a = b = 13.6490 ?, c = 9.1123 ?, γ = 120.00° and Z = 18. Structure of the crystal is constructed by LiO_4, ZnO_4 and PO_4 tetrahedral units to form a three-dimensional(3 D) framework. The crystal has a high transmission ranging from 350 to 800 nm with UV cut-off edge at 220 nm. The nonlinear optical efficiency of the as-prepared β-LiZnPO_4 is about 1.2 times as large as that of KDP(KH_2PO_4) standard. Additionally, band structure and density of states calculations for β-LiZnPO_4 were performed using the total-energy code CASTEP, based on density functional theory(DFT).     

Li3AlB2O6： Synthesis, Crystal Structure, and Its Luminescence Property Compared with LiSrBO3

The synthesis and crystal structure of Li3AlB2O6 with different cell parameters are reported and these cells are transformed each other from the confirmation of crystallographic structural analyses. The absorption spectrum, luminescence and lifetimes of the Li3AlB2O6 and LiSrBO3 solid compounds are measured and the comparisons are made between them. It is shown that the absorption edges are at about 400 nm (or band gap 3.1 eV) and there is one of absorption peaks at about 350 nm for the Li3AlB2O6 and LiSrBO3. The emission band (530 nm) makes a red shift and fluorescence decay time (24.39 ns) of the Li3AlB2O6 becomes smaller compared with the emission band (480 nm) and lifetime (93.16 ns) of the LiSrBO3 at the visible region. The transition energies and oscillator strengths of the clusters (Li3AlB2O6)2 and (LiSrBO3)2 lying at low excited states are calculated by the time-dependent Hartree-Fock method. The obtained results are used to model the photophysical properties and discuss the origin of spectral bands of the Li3AlB2O6 and LiSrBO3.     

Two Novel Homochiral Enantiomorphic 3D Metal-organic Frameworks： Synthesis, Crystal Structure, Luminescent and SHG Properties

Two homochiral enantiomorphic 3D coordination polymers： （D-HAPA）2[Cd2Cs（D- HAPA）（m-BDC）4]＇（EtOH） （1D） and （L-HAPA）2[Cd2Cs（L-HAPA）（m-BDC）a]＇（EtOH） （1L） （APA = 2-amino-l-propanol, m-H2BDC = 1,3-benzenedicarboxylate）, have been assembled solvothermally respectively with the induction of enantiomorphic organic small molecules （D,L-APA）. 1L and 1I） crystallize in chiral space group P21 with Flack parameters of-0.012（13） and -0.07（3）, respectively, and have been characterized by satisfactory elemental analysis, FT-IR spectra, CD-spectra and single-crystal X-ray diffraction. They both exhibit sqp topological net, purple fluorescence and SHG activity.     

Structure and properties of glasses in the system Li2O–SnO–B2O3

Glasses in the system Li₂O–SnO–B₂O₃ system were prepared by a melt-quenching method. Thermal and viscous properties and local structure of these glasses were investigated. The SnO–B₂O₃ glasses exhibited relatively low glass-transition temperatures (T_g) around 350 °C and excellent thermal stability against crystallization. Viscosity measurements in the vicinity of T_g indicated that the glasses were considerably fragile compared to alkali borate glasses. Fraction of four-coordinated boron was maximized at the composition with 50 mol% SnO and that of nonbridging oxygen, which is not purely ionic in alkali borate systems but partially covalent, augmented with an increase in the SnO content. Correlation between glass properties and structure was discussed in the SnO–B₂O₃ binary system.     

Ion mobility spectrometry in scientific literature and in the International Journal for Ion Mobility Spectrometry (1998–2007)

Starting in 1998 the International Society for Ion Mobility Spectrometry, organising the annual conferences on ion mobility spectrometry, began to issue the International Journal for Ion Mobility Spectrometry. Now, in the 11th year the journal will be the first year together with SPRINGER. Therefore, the article focusses on the history of IMS providing an up to date account based on a systemetic search using the Web-of-Science and SciFinder search engines.     

Low Temperature Synthesis,Structure and Bioactivity of 2CaO⋅3SiO2 Glass

Glasses of composition 2CaO3SiO₂ were prepared by means of the sol-gel route starting from tetramethyl orthosilicate and calcium nitrate tetrahydrate and the melt-quenching technique from a mixture of oxides. Their structures were compared. The infrared spectra suggest that the gel derived glass has a different structure than the corresponding melt quenched glass, having a more uniform distribution of non-bridging oxygens among the SiO₄ tetrahedra. Owing to its porosity, the gel derived glass is more prone to devitrify than the melt quenched glass is. The infrared spectra relative to samples soaked in a fluid simulating the composition of the human blood plasma suggest that the gel derived glass is more bioactive than the melt quenched glass is.     

Synthesis and Crystal Structure of 2-Amino-I, 1-diferrocenylethanol

2-Amino-l,l-diferrocenylethanol 2 was prepared by reduction of trimethylsilylcyanohydrin ether of diferrocenyl ketone. The crystal structure of 2 was further defined by X-raydiffraction.     

Gas-Phase Structure of Amyloid-β (12 – 28) Peptide Investigated by Infrared Spectroscopy, Electron Capture Dissociation and Ion Mobility Mass Spectrometry

The gas-phase structures of doubly and triply protonated Amyloid-β_12-28 peptides have been investigated through the combination of ion mobility (IM), electron capture dissociation (ECD) mass spectrometry, and infrared multi-photon dissociation (IRMPD) spectroscopy together with theoretical modeling. Replica-exchange molecular dynamics simulations were conducted to explore the conformational space of these protonated peptides, from which several classes of structures were found. Among the low-lying conformers, those with predicted diffusion cross-sections consistent with the ion mobility experiment were further selected and their IR spectra simulated using a hybrid quantum mechanical/semiempirical method at the ONIOM DFT/B3LYP/6-31 g(d)/AM1 level. In ECD mass spectrometry, the c/z product ion abundance (PIA) has been analyzed for the two charge states and revealed drastic differences. For the doubly protonated species, N – C_α bond cleavage occurs only on the N and C terminal parts, while a periodic distribution of PIA is clearly observed for the triply charged peptides. These PIA distributions have been rationalized by comparison with the inverse of the distances from the protonated sites to the carbonyl oxygens for the conformations suggested from IR and IM experiments. Structural assignment for the amyloid peptide is then made possible by the combination of these three experimental techniques that provide complementary information on the possible secondary structure adopted by peptides. Although globular conformations are favored for the doubly protonated peptide, incrementing the charge state leads to a conformational transition towards extended structures with 3₁₀- and α-helix motifs.      

Isolation of the Metalated Ylides [Ph3P−C−CN]M (M=Li,Na, K): Influence of the Metal Ion on the Structure and Bonding Situation

The isolation and structural characterization of the cyanido-substituted metalated ylides [Ph₃P−C−CN]M ( 1-M ; M=Li, Na, K) are reported with lithium, sodium, and potassium as metal cations. In the solid-state, most different aggregates could be determined depending on the metal and additional Lewis bases. The crown-ether complexes of sodium ( 1-Na ) and potassium ( 1-K ) exhibited different structures, with sodium preferring coordination to the nitrogen end, whereas potassium binds in an unusual η²-coordination mode to the two central carbon atoms. The formation of the yldiide was accompanied by structural changes leading to shorter C−C and longer C−N bonds. This could be attributed to the delocalization of the free electron pairs at the carbon atom into the antibonding orbitals of the CN moiety, which was confirmed by IR spectroscopy and computational studies. Detailed density functional theory calculations show that the changes in the structure and the bonding situation were most pronounced in the lithium compounds due to the higher covalency.     

Design,Synthesis, Evaluation and Structure of Allenic 1α,25-Dihydroxyvitamin D3 Analogs with Locked Mobility at C-17

Vitamin D receptor ligands have potential for the treatment of hyperproliferative diseases and disorders related to the immune system. However, hypercalcemic effects limit their therapeutical uses and call for the development of tissue-selective new analogs. We have designed and synthesized the first examples of 1α,25-dihydroxyvitamin D₃ analogs bearing an allenic unit attached to the D ring to restrict the side-chain conformational mobility. The triene system was constructed by a Pd⁰-mediated cyclization/Suzuki-Miyaura cross-coupling process in the presence of an allenic side chain. The allenic moiety was built through an orthoester-Claisen rearrangement of a propargylic alcohol. The biological activity and structure of (22S)-1α,25-dihydroxy-17,20-dien-24-homo-21-nor-vitamin D₃ bound to binding domain of the vitamin D receptor, provide information concerning side-chain conformational requirements for biological activity.     

Orthorhombic γ-LiV2O5 as Cathode Materials in Lithium Ion Batteries: Synthesis and Property

The rod-like and bundle-like γ-LiV₂O₅ were synthesized via a simple solvothermal process-ing. The rod-like γ-LiV₂O₅ with diameter of 500-800 nm and the bundle-like architectures are composed of several of order-attached rods with diameter of 100-600 nm. γ-LiV₂O₅ were synthesized using LiOH·H₂O, NH₄VO₃, HNO₃, C₂H₅OH without and with PVP as raw materials. At the same time, the actual formation mechanism of γ-LiV₂O₅ was also investigated. As the cathode materials for lithium ion batteries, the bundle-like γ-LiV₂O₅ prepared with PVP delivers a better electrochemical performance, which has an initial dis-charge capacity of 269.3 mAh/g at a current density of 30 mA/g and is still able to achieve 228 mAh/g after the 20th cycle. The good electrochemical properties of the as-synthesized γ-LiV₂O₅ coupled with the simple, relatively low temperature, and low cost of the prepara-tion method may make this material a promising candidate as a cathode material for lithium ion batteries.     

2-Hydroxy-1, 1-Biphenyl- and -Binaphthyl-2′-Phosphines - Synthesis,Structure and Use in Rh-Catalyzed Carbonylation

Abstract

Dibenzofuran and dinaphthofuran are cleaved by lithium in presence of electron transfer catalysts to yield C,O-dilithium reagents. These are reacted with chloro- or alkoxyphosphines providing 2-hydroxy-1,l ‘-biphenyl-2’-phosphines and 2-hydroxy-1,‘-binaphthyl-2’-phosphines which form solvent complexes with O…H?O or P…H?O bridging bonds. The planes of the benzene rings of the biphenyl units are nearly perpen-dicular in the unit cell. Line form analysis of the temperature dependent solution NMR spectra of diastereoisomeric 2-HO-C₆H₄-C₆H₄-P (tBu)Ph revealed a barriere of rotation of Δ H= 12.87 kcal/mol. The respective 0-trimethylsilyl ethers have a higher barrier, and 2-hydroxybinaphthyl-2-phosphines dont racemize after separation by HPLC.     

Synthesis,Crystal Structure and Optical Properties of KPr（MoO4）2 with the Scheelite-type Structure

Solid-state reaction of praseodymium （III） oxide,K2CO3 and MoO3 at high temperature leads to a potassium lanthanide double molybdate,namely,KPr（MoO4）2. The structural and optical properties of the title compound have been investigated by means of single-crystal X-ray diffraction and spectroscopic measurements at room temperature. KPr（MoO4）2 crystallizes in tetragonal,space group I41/a with a = 5.401（3）,c = 12.044（10）,Z = 2 and R （I 〉 2σ（I）） = 0.0416. It features the famous scheelite-type structure （CaWO4）,which can be thought as the substitution of two Ca^2＋ ions in CaWO4 by a couple of K^＋ and Pr^3＋ ions in a statistical manner,and W^6＋ by Mo^6＋ cations.     

Synthesis and Structure of the Complexes of 2-Alkoxycarbonylalkyltin Trichlorides with 2-Salicylideneaminophenol

SinceHutton]developedanovelr0utet0preparationofthe2-alkoxycarbonylalkyltintrichIorides,R'OCOCHRCH,SnCI,(l),lhavereceivedconsiderableattenti0nbecauseofthevarietyofcoordinationgeometriesaboutthetinatom.2-'Previ0usly,wehadre-portedtheadducts0flwithneutraIdonorssuchasDMSO,HMPA,bpyandphen.'-'Inthispaper,wereportthesynthesis0fthecomplexes0flwithnegativebivaIentligandderivedfr0m2-salicylideneamin0phenop(H2L),R'OCOCHRCH,SnClL(R=H,Me,R'=Me,Et,n-Pr,Allyl,n-Bu),andthecrystaIstructureof…     

Metal Complexes of Donor-functionalized Fluorinated β-Ketoiminates – Synthesis,Structure, and CVD Application

Six alkali metal complexes of partly-fluorinated, donor-functionalized β-ketoiminate ligands [L¹Li ( 1 ), L¹Na ( 2 ), L¹K ( 3 ), L¹Cs ( 4 ), L¹ = OC(CF₃)CHC(CH₃)NCH₂CH₂OCH₃; L²Li ( 5 ), L²Na ( 6 ), L² = OC(CF₃)CHC(CH₃)NCH₂CH₂N(CH₃)₂] were prepared and structurally characterized. Reactions of L¹Li with PtCl₂ gave the homoleptic Pt complex L¹₂Pt ( 7 ), which was characterized spectroscopically and by single-crystal X-ray diffraction and whose promising application as CVD precursor (chemical vapor deposition) is shown. Polycrystalline, pure Pt films were grown at 500 °C on SiO₂@Si(100) substrates at 10^–3 mbar and characterized by XRD, SEM, AFM, EDX and XPS.     

Lithium-cation Conduction and Crystallochemical Features of Solid Solutions La2/3 – x Li3x□4/3 – 2x Nb2O6 with the Structure of Fault Perovskite

Transport properties and crystallochemical features of lithium-containing lanthanum metaniobates La_{2/3 – x} Li_{3x4/3 – 2x} Nb₂O₆ with the structure of fault perovskite are studied. The materials studied have high conductivity by lithium ions. A correlation between the conductivity magnitude, chemical composition, and crystallographic parameters is found.     

Synthesis and Crystal Structure of 2-Amino-1, 1-diferrocenylethanol

2-Aminoalcohols are useful intermediates in organic chemistry, for example, they serve for the synthesis of various heterocycles1, chelate complexes2, and for the ring expansion of cycloalkanones3. 2-Aminoalcohols containing ferrocene as bidentate ligand may be converted into multinuclear compounds. Several methods for the preparation of 2-aminoalcohols have been developed including reduction of the trimethylsilyl cyanohydrins4 or β-nitromethyl alcohols5 and treatment of the epoxides with a…