Synthesis,Crystal Structure,and Hirshfeld Surface Analysis of Rubidium trans-Bis(N-methyliminodiacetato)chromate(III)

Crystallography Reports - A new rubidium salt, Rb[Cr(C5H7NO4)2] (C5H7NO4 = mida, methyliminodiacetate), was prepared and its molecular structure was determined from synchrotron X-ray data at 173 K....     

Synthesis, spectroscopy, and X-ray structures of fac-(CO)3(dppe)MnSC(S)H, fac-(CO)3(dppe)ReSC(S)H, fac-(CO)3(dppp)ReSC(S)H, and fac-(CO)3(dppb)ReSC(S)H

The monodentate dithioformato complexes, fac-(CO)₃(dppe)MnSC(S)H (1), fac- (CO)₃(dppe)ReSC(S)H (2), fac-(CO)₃(dppp)ReSC(S)H (3), and fac-(CO)₃ (dppb)ReSC(S)H (4), where dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, and dppb is 1,4-bis(diphenylphosphino)butane, were synthesized from the treatment of the corresponding hydrides, fac-(CO)₃ (P-P)MSC(S)H with CS₂. Compounds 1–4 crystallize in the monoclinic crystal system: for 1, space group = P2₁/c, a = 15.3139(3) Å, b = 9.7297(4) Å, c = 19.0991(6) Å, = 105.928(1), V = 2736.5 ų, Z = 4; for 2, space group = P2₁/c, a = 15.6395(8) Å, b = 9.8182(5) Å, c = 19.4153(11) Å, = 106.741(1), V = 2854.9(3) ų, Z = 4; for 3, space group = P2₁/n, a = 11.3570(10) Å, b = 19.465(2) Å, c = 15.5702(14) Å, = 104.776(2), V = 3328.3(5) ų, Z = 4; and for 4, space group = C2/c, a = 32.078(2) Å, b = 10.4741(6) Å, c = 19.0608(9) Å, = 94.315(2), V = 6386.1(6) ų, Z = 8.     

Tri-(nitrato)-bis-(hexamethylenetetramine)-nona-(aquo) neodymium (III): Synthesis,crystal structure,IR and Raman spectroscopy

This paper reports the structural and spectroscopic properties of tri-(nitrato)-bis-(hexamethylene-tetramine)-nona-(aquo)neodymium (III). The crystals are monoclinic, space groupP2₁/n,Z=4, witha=17.902(4),b=9.335(2),c=18.489(4)Å, B=112.07(2)°. The crystal structure consists of one [Nd(NO₃)₂(H₂O)₆]⁺ cation, two NO ₃ ^– anions coordinated to the neodymium atom, two hexamethylene tetramine molecules, third free NO ₃ ^– anion and three water molecules. The structure was refined to a finalR index 0.039 and weightedR _w 0.039 for 6221 observed reflections. The IR and Raman spectra are fully consistent with the crystallographic results.     

Tris-(thiocyanato)-bis-(hexamethylenetetramine)-nona-(aquo) lanthanum(III): synthesis, crystal structure, IR and Raman characterization

The title compound (LaC₁₅H₄₂N₁₁O₉S₃) was prepared and characterized by means of X-ray, IR and Raman measurements. The crystals are orthorhombic: Pnma (No. 62), a = 21.117(2), b = 14.736(2), c = 10.082(1) Å, and Z = 4. The structure consists of polyhedra with a La(III) ion in the center of them and hexamethylene molecules, which link these polyhedra. Each La(III) ion coordinates seven molecules of water and two thiocyanate ions via nitrogen atoms. The IR and Raman spectra, which have been obtained and interpreted, are in good agreement with X-ray results.     

Chemical Synthesis,X-ray Crystallography,Hirshfeld Surface Analysis,and Molecular Docking Studies of (E)-2-(((3-Bromophenyl)imino)methyl)-5-(diethylamino)phenol Schiff Base

Crystallography Reports - The title Schiff base compound (I), C17H19BrN2O, has been synthesized by the reaction of 4-(diethylamino)-2-hydroxybenzaldehyde and 3-bromoaniline. The dihedral angle...     

Synthesis and Characterisation of Scandium (III)-, Yttrium (III)-, and Lanthanum (III) Violurate Complexes

Sc³⁺-, Y³⁺ -and La³⁺ violurate complexes were prepared. The isolated complexes are freely soluble in water, dilute mineral acids, MeOH, Me₂CO, DMF, DMS, partially soluble in AcOH and insoluble in EtOH, CHCl₃ and CCl₄. Molecular compositions of the complexes were formulated on the basis of elemental analysis, molar conductivity and infrared spectra. The IR spectra of violuric acid and its metal complexes reveal that bonding takes place through coordination bond between the central metal ion and the oxygen atom of the oxygen atom of the oximino (C N = O) group and convalenet bond between the central metal ion and oxygen atom of the phenolic (ketonic, C O H) group in the case of 1:2 and 1:3 complexes, and through coordination bond between the central metal ion and C O H and N H groups in the case of 2:3 complexes. All the isomorphous complexes detected by the X-ray powder patterns [the (2:3) Sc³⁺-VA and (2:3) Y³⁺-VA complexes, (1:2) Sc³⁺-VA, (1:2) Y³⁺-VA and (1:2) La³⁺-VA complexes, and the (1:3) Y³⁺-VA and (1:3) La³⁺-VA complexes] have similar X-ray, eletronic and IR spetrograms and chemical formulae. The electronic spectra in DMF and in nujol mulls characterise the octahedral stereochemistry for the investigated complexes.     

Preparation,properties, and crystal structure of bis(acetylcholine)tetrabromodioxouranium(VI)

The compound bis(acetylcholine)tetrabromodioxouranium(VI), [C₇H₁₆-NO₂]₂ UO₂ Br₄, has been prepared and its physicochemical properties studied. No influence of the uranyl-bromide system on the muscarinic conformation of acetylcholine in the adduct was inferred on the basis of biological activity measurements. This lack of effect on the acetylcholine molecule by [UO₂Br₄]^2– anion is confirmed by X-ray structure determination. The crystals are orthorhombic, space groupPnma,Z = 4,a =13.60(2),b = 20.94(3),c = 9.22(2) Å. The conventional discrepancy index is 0.087 for 1822 diffractometer data. Some disorder is observed in the acetylcholine molecule.Abbreviations AcCh Acetylcholine - [AcCh]₂UO₂Br₄ bis(acetylcholine)tetrabromodioxouranium(VI) - AcChE Acetylcholinesterase     

Molecular beam epitaxy growth and properties of GaAs/(AlGa)As p-type heterostructures on (100), (011), (111)B, (211)B, (311)B, and (311)A oriented GaAs

We report on a series of Be-doped GaAs/AlGaAs two-dimensional hole gas (2DHG) structures grown on (110), (111)B, (211)B and (311)B oriented substrates and compare their properties with high-mobility samples grown on (311)A using Si doping. The samples were prepared and grown under the same conditions so as to render them comparable. They are found to have mobilities which are strongly anisotropic within the plane. The highest mobility is found on the (110) surface with 100,000 cm² V⁻¹ s⁻¹, while the (211) surface gave the lowest values 10,000 cm² V⁻¹ s⁻¹. However, the later samples are found to have quantum Hall effect critical currents of >70 μA: an exceptionally high value for a hole gas which makes them suitable for metrology. All the samples show strong low-field positive magnetoresistance with resistance increases of up to 30% at magnetic fields of only 0.1 T. The presence of this feature on all the different planes shows that it does not depend upon the details of the band structure. It is identified with the lifting of the degeneracy of the spin sub-bands by the asymmetrical potential giving rise to a classical two-band magnetoreresistance.     

ZnO@Si(100) and ZnO@Si(111): Hydrothermal Synthesis,Morphology, and Lasing Characteristics

Crystallography Reports - Microstructures have been formed on single-crystal silicon substrates of different crystallographic orientations, (111) and (100), under “soft” hydrothermal...     

钙钛矿型层状化合物K_2Ln_2Ti_3O_(10)(Ln=La,Pr,Sm,Eu,Gd)X射线衍射晶体结构分析

固相反应法合成了具有钙钛矿型层状的化合物K_2Eu_2Ti_3O_(10) 和K_2Gd_2Ti_3O_(10) ,利用X射线粉晶衍射仪对镧系元素的钙钛矿型层状化合物K_2Ln_2Ti_3O_(10) (Ln=Eu,Gd)进行结构分析,获得其X射线粉晶衍射数据.X射线衍射分析结果表明:K_2Ln_2Ti_3O_(10) (Ln= La,Pr,Sm,Eu,Gd )为四方晶系,空间群I4/mmm.并得到其晶胞参数及其镧系元素的钙钛矿型层状化合物K_2Ln_2Ti_3O_(10) 晶体结构变化规律.     

Platinum(II) dibromo,bis (3,5-diamino-1(2)-triazolium) dibromide: Synthesis,crystal and molecular structure,and infrared characterization

The title compound C₄H₁₂PtN₁₀Br₄ was prepared and characterized by means of X-ray, and IR measurements. The crystals are monoclinic, space groupP2₁/c, (C _2h ⁵ No. 14) witha=6.875(1),b=15.478(2),c=7.074(1)Å,=90.98(1) andZ=2. The structure was solved by the heavy-atom method, and least-squares refinement of structural parameters led to a conventionalR factor of 0.031 (R _w=0.030) for 733 independent reflections. The compound exhibits discrete monometallic units with the 1,2,4-triazolium ion acting as modentate ligand. The structure consists of centrosymmetric units in which the platinum atom is coordinated in perfectly planar geometry by two nitrogen and two bromine atoms. The NH and NH₂ group of the guanazolium unit are involved in intermolecular hydrogen bonds. Infrared bands are diagnostic of the coordination environments around the metal atoms.     

Crystal structure of p-formylphenyl, di(p-methylphenyl)amine, and p-bromophenyl, di(o-bromo-p-methylphenyl)amine

p-Formylphenyl, di(p-methylphenyl)amine (1), and p-bromophenyl, di(o-bromo-p-methylphenyl)amine (2) were prepared and characterized by X-ray crystallography. Formyl-substituted triphenylamine(1) crystallizes in the monoclinic space group P2₁/c with a = 9.068(1), b = 17.115(2), c = 11.297(2) Å, = 106.73(1)°, V = 1679.0(5) ų and Z = 4. Bromo-substituted compound 2 crystallizes in the monoclinic space group P2₁/n with a = 16.170(4), b = 7.9477(8), c = 16.906(4) Å, = 117.67(2)°, V = 1924.1(7) ų and Z = 4. The N atoms deviate slightly from the plane of the bonded C atoms and the benzene ring planes are rotated by 25–67° to avoid overlap of the ortho-substituted atoms. The major force of crystal formation comes from the multiple phenyl embraces (MPE).     

Synthesis, spectroscopy, magnetism, and X-ray structures of hexakis(1-(2-chloroethyl)-tetrazole-N4)copper(II) salts

The compounds hexakis(1-(2-chloroethyl)-tetrazole-N4)copper(II) tetrafluoroborate mono(1-(2-chloroethyl)-tetrazole) (1) and hexakis(1-(2-chloroethyl)-tetrazole-N4) copper(II) perchlorate mono(1-(2-chloroethyl)-tetrazole) (2) were obtained from the crystallization of 1-(2-chloroethyl)-tetrazole (teec) with the respective copper salt. The X-ray structures are reported. Both compounds crystallize in the monoclinic space group C2/c for 1: a = 25.754(3) Å, b = 18.162(3) Å, c = 10.298(2) Å = 104.294(7)° and Z = 4 and for 2: a = 25.745(3) Å, b = 18.197(3) Å, c = 10.29355(3) Å = 104.512(10)° and Z = 4. The Cu^II ions are octahedrally surrounded by six teec ligands. One free teec ligand is present in the structures. The Cu–N distances in the centrosymmetrical units are 2.01, 2.04, and 2.39 Å in both compounds, consistent with a Jahn–Teller elongated octahedron. The ligand field spectra of both compounds show a signal in the visible range at about 15.200 cm^–1 and by an EPR spectrum the following values are found: g _| = 2.29 and g = 2.03. The compounds are both paramagnetic and the T value of 0.37 cm^–1 K mol^–1, which is associated with S = 1/2, is what would be expected for a mononuclear Cu^II complex.     

Synthesis and X-Ray Crystallographic Analysis of 2-(2, 4-Dimethyl Pyrrolyl) Benzothiazole

Abstract  

Synthesis of 2- (2, 4-dimethyl pyrrolyl) benzothiazole by chemical means and molecular structure by X-ray crystallographic techniques is reported. The compound crystallizes in the orthorhombic crystal system with space group Pbca and unit cell parameters: a = 12.161(9), b = 0.787(1), c = 16.792(2) Ǻ, V = 2202.8(4) Ǻ³ and Z = 8. The final reliability index is 0.073 for 7,959 observed reflections. The benzothiazole and pyrrole rings exist in planar conformations. The dihedral angle between the least-squares planes of both these moieties is 13.31°. There exists an isolated C4–H4···N1 intermolecular interaction, besides two C–H···S and C–H···N intermolecular interactions. The presence of C–H···S and C–H···N intramolecular interactions make the present molecule look like a virtual two-six-membered and three-five-membered ring structure.     

过渡金属离子(Mn,Fe,Co)掺杂铝酸锂晶体的生长及光谱分析

采用提拉法分别生长了掺杂Mn、Fe以及Co元素的LiAlO2晶体,并对其结晶质量和光谱特性进行了研究.结果表明,LiAlO2:Mn、LiAlO2:Fe和LiAlO2:Co晶体的X射线双晶摇摆曲线半高宽分别为23.2 arcsec、12.9 arcsec和23.8 arcsec.LiAlO2:Mn与LiAlO2:Fe晶体在可见至近红外波段具有较高的透过率,而LiAlO2:Co晶体在500～700 nm波段存在吸收带;光致激发与发射光谱表明Mn2+在LiAlO2:Mn晶体中处于四面体晶体场内,而Fe3+替代Li+处于八面体格位;X射线激发发射光谱分析得出空气退火后γ-LiAlO2晶体出现了较强的缺陷发光,可归结为Li2O挥发后形成的F+心,而在同样退火条件下掺杂LiAlO2晶体中相应的缺陷发光不明显,说明Li2O的挥发被抑制,晶体的热稳定性得到了改善.     

Synthesis,thermal, spectroscopic,and X-ray studies of (dichloroacetato)(triphenylphosphine)gold(I)

The synthesis, thermal, spectroscopic, and X-ray investigation of (dichloroacetato) (triphenylphosphine)gold(I), [Au(C₂HCl₂O₂)(C₆H₅)₃P] are reported. The thermal analysis showed that the decomposition of the studied complex is a two step process and the mechanism of the decomposition has been proposed. IR and¹³C NMR spectra of the complex are given. The compound crystallizes in the monoclinic space groupP2 ₁/n with four molecules per unit cell.M _r =587.19,a=11.455(1),b=12.398(3),c=14.718(2)Å,=104.95(1)°,V=2019.5(6)ų,D _x=1.931g/cm³,(Cu K)=172.6 cm^–1,F(000)=1120. FinalR=0.059 for 2780 absorption-corrected reflections. The crystals are not isostmctural with acetato(triphenylphosphine) gold(I) and (trifluoroacetato)-(triphenylphosphine)gold(I). The Au-O1 bond length is of 2.049(9), Au-P of 2.210(3)Å with O1-Au-P angle of 176.9(2)°.     

Diaquabis(5-methoxyindole-2-carboxylato)bis(3-picoline)nickel(II) Complex: Synthesis,Characterization, XRD,TGA, DFT and HSA

A new complex of diaquabis(5-methoxyindole-2-carboxylato)bis(3-picoline)nickel(II) (Ni(5-MeOI2CA)₂(3-pic)₂(H₂O)₂), was synthesized for the first time and characterized by elemental analysis, FT-IR and electronic spectroscopy (UV-Vis) and single-crystal X-ray diffraction (XRD) techniques. The thermal degradation of the Ni(II) complex was investigated using thermogravimetric and differential thermal analyses techniques in oxygen atmosphere. The molecular structure of the complex was determined by single crystal X-ray diffraction technique. Hirshfeld surface analysis (HSA) investigated the packing modes and intermolecular interactions in molecular crystals, as they provide a visual picture of intermolecular interactions. In addition, all computational studies at B3LYP/6-311++G(d,p) were carried out for theoretical characterization of Ni(II) complex. The optimized geometry results, which were well represented the X-ray data, were shown that the chosen of DFT/B3LYP/6-311++G(d,p) was a successful choice for title compound. After a successful optimization, FMOs, chemical activity, non-linear optical properties (NLO), molecular electrostatic potential (MEP), Mulliken population (MPA), natural population analyses (NPA), Fukui function analysis (FFA) and natural bond orbital analysis (NBO), which could not obtained by experimental ways, were calculated and investigated. The computed of net charges and chemical activity studies which helped to identifying the electrophilic/nucleophilic nature.