scholarly journals The Synthesis and Study of Tetranuclear Cluster [Fe4O2(CCl3COO)8(THF)2(DMF)(H2O)]⋅THF

2006 ◽  
Vol 1 (1) ◽  
pp. 77-83
Author(s):  
Denis Prodius ◽  
Valeriu Mereacre ◽  
Shova Sergiu ◽  
Maria Gdaniec ◽  
Yurii Simonov ◽  
...  
Keyword(s):  
Coordination Number ◽  
Magnetic Measurements ◽  
The Novel ◽  
Antiferromagnetic Exchange ◽  
Spin Hamiltonian ◽  
Magnetic Studies ◽  
Tetranuclear Cluster ◽  
X Ray ◽  
Infra Red ◽  
Fitting Parameters

The novel bis(μ3-oxo) tetranuclear trichloracetate cluster, [Fe4O2(CCl3COO)8(THF)2(DMF)(H2O)]⋅THF (1), has been synthesised and subsequently characterised by X-ray structure analysis, magnetic measurements and infra red (IR). The structure of cluster is “butterfly” type. The Fe···Fe separation has the value of 2.883(1) - 3.441(7) Å. The coordination number of iron (III) is 6. Magnetic studies reveal the presence of an antiferromagnetic exchange in the parallelogram skeletons of the tetranuclear species. Using the spin Hamiltonian H = -2Jwb(Ŝ1Ŝ2 + Ŝ2Ŝ3 + Ŝ3Ŝ4 + Ŝ4Ŝ1) - 2JbbŜ2Ŝ4v+ gμβ(Ŝ1z + Ŝ2z +Ŝ3z + Ŝ4z)B, the fitting parameters Jbb = - 14.3 cm-1, Jwb = - 32.1 cm-1 , g = 2.07, ρparam. -5 impur. = 4.2 %, ΘCurie-Weiss const. = -0.5 K and R = 6.8·10 were obtained.

Two New Copper (II) Complexes with the Same NNO Donor Schiff Base Ligand: A Monomer and a Dimer

2012 ◽  
Vol 67 (3) ◽  
pp. 192-196
Author(s):  
Bao Lin Liu ◽  
Yan Xia Wang ◽  
Ruo Jie Tao
Keyword(s):  
Experimental Data ◽  
Thermal Analysis ◽  
Schiff Base ◽  
Magnetic Measurements ◽  
Octahedral Geometry ◽  
Distorted Octahedral Geometry ◽  
Antiferromagnetic Exchange ◽  
X Ray ◽  
Distorted Octahedral ◽  
Best Fit

Two new copper(II) complexes, [(CuL)2(μ1,1-N3)2]・2H2O (1) and [Cu(HL)(2,2ʹ-bipy)- (CH3COO)]・ClO4・H2O (2), have been synthesized using the tridentate NNO Schiffbase ligand 2- [(2-aminoethylimino)methyl]-6-methoxyphenol (HL). They have been characterized by elemental analysis, IR spectroscopy, thermal analysis, and single-crystal X-ray analysis. The copper environment is distorted square pyramidal in complex 1: two nitrogen atoms and one oxygen atom from the ligands and two nitrogen atoms from two azido ligands build the coordination polyhedron around the copper atom. The Cu-Nazide-Cu angle in complex 1 is 85.6°. This is unusually small in comparison with the same angle in other end-on doubly azido-bridged dimers. Complex 2 is mononuclear with the Cu atom having a slightly distorted octahedral geometry. Magnetic measurements of 1 have been performed in the temperature range from 2 to 300 K. The experimental data indicate an antiferromagnetic exchange interaction between copper(II) ions bridged by the azido ligand. The best-fit parameters for complex 1 are g = 2.18 and J = −1.31 cm−1.

Oligometallic cobalt 3,5-dimethylpyrazolate complexes: synthesis, structural and magnetic studies

1993 ◽  
Vol 71 (9) ◽  
pp. 1425-1436 ◽  
Author(s):  
Martin K. Ehlert ◽  
Steven J. Rettig ◽  
Alan Storr ◽  
Robert C. Thompson ◽  
James Trotter
Keyword(s):  
Magnetic Data ◽  
Antiferromagnetic Coupling ◽  
Antiferromagnetic Exchange ◽  
Nearest Neighbour ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Dimer Model ◽  
Space Group ◽  
X Ray ◽  
Susceptibility Data

Three oligometallic 3,5-dimethylpyrazolate (dmpz) bridged Co(II) compounds have been synthesized and characterized spectroscopically: dimeric [Co(dmpz)2(Hdmpz)]2, the related oligometallic compound, Co(dmpz)2•0.344(Hdmpz), and the trimetallic [Co(dmpz)2Cl(Hdmpz)]2Co. The first and last of these compounds have been studied magnetically and by single crystal X-ray diffraction. Crystals of [Co(dmpz)2(Hdmpz)]2 are orthorhombic, a = 17.022(1), b = 29.224(2), c = 13.576(3) Å, Z = 8, space group Fddd; and those of [Co(dmpz)2Cl(Hdmpz)]2Co are triclinic, a = 11.742(3), b = 18.604(4), c = 8.950(2) Å, α = 99.76(2)°, β = 102.32(2)°, γ = 93.36(2)°, Z = 2, space group [Formula: see text] The structures were solved by the Patterson method and were refined by full-matrix least-squares procedures to R = 0.035 and 0.042 (Rw = 0.034, 0.047) for 938 and 3853 reflections with I ≥ 3σ(F2), respectively. Magnetic susceptibility studies on the dimeric and trimetallic complex show them to exhibit antiferromagnetic behaviour. Analysis of the magnetic data (2– 300 K) for the trimetallic complexes reveals antiferromagnetic coupling between the terminal and central Co(II) ions with J (Heisenberg) ≈ −3 cm−1. Either intramolecular next-nearest neighbour or intermolecular antiferromagnetic exchange is also present in this compound. The dimeric complex shows significant antiferromagnetic exchange between cobalt centres. Susceptibility data over the range 12–300 K are adequately modelled with the Ising S = 1/2 dimer model (J ≈ −23 cm−1).

The solid solutions CeRu1–xPdxSn and CeRh1–xPdxSn – Applicability of the ICF model to determine intermediate cerium valencies by comparison with XANES data

2015 ◽  
Vol 70 (4) ◽  
pp. 253-264 ◽  
Author(s):  
Oliver Niehaus ◽  
Paula M. Abdala ◽  
Rainer Pöttgen
Keyword(s):  
Solid Solutions ◽  
Valence Electron ◽  
Magnetic Measurements ◽  
Edge Structure ◽  
X Ray ◽  
Arc Melting ◽  
Best Fitting ◽  
Icf Model ◽  
X Ray Absorption ◽  
Fitting Parameters

AbstractSeveral samples of the solid solutions CeRu1–xPdxSn and CeRh1–xPdxSn have been synthesized by arc-melting and characterized by X-ray powder diffraction. Guinier powder patterns prove that the ZrNiAl-type structure is the dominating one, besides the CeRuSn and TiNiSi type structures. The structures of CeRu0.28Pd0.72Sn (ZrNiAl type, P6̅2m, a = 751.95(3), c = 418.70(2) pm, wR2 = 0.0274, 332 F2 values, 14 variables) and CeRh0.66Pd0.34Sn (ZrNiAl type, P6̅2m, a = 750.26(3), c = 411.59(2) pm, wR2 = 0.0533, 358 F2 values, 14 variables) were refined from single crystal diffractometer data. Magnetic measurements in combination with XANES (X-Ray Absorption Near Edge Structure) clearly proved intermediate cerium valencies for most compounds and revealed the best fitting parameters for those with the ICF model (Interconfiguration fluctuation). The electrical resistivity is also influenced by the substitutions. At low and high valence electron counts (VECs) metallic character is present, while around the VEC of CeRhSn the typical resistivity behavior for valence fluctuating compounds is observed.

Electron Microscopy of Human Gallstones

1971 ◽  
Vol 29 ◽  
pp. 296-297
Author(s):  
C. Wolpers ◽  
R. Blaschke
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bile Pigment ◽  
X Ray Diffraction ◽  
Triclinic Crystal System ◽  
X Ray ◽  
Follow Up Study ◽  
Infra Red ◽  
Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

PENGGUNAAN TiO2 PARTIKEL NANO HASIL SINTESIS BERBASIS AIR MENGGUNAKAN METODA SOL-GEL PADA BAHAN KAPAS SEBAGAI APLIKASI UNTUK TEKSTIL ANTI UV

Arena Tekstil ◽  
2013 ◽  
Vol 28 (1) ◽  
Author(s):  
Maya Komalasari ◽  
Bambang Sunendar
Keyword(s):  
Fourier Transform ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sol Gel ◽  
Crosslinking Agent ◽  
X Ray Diffraction ◽  
Nano Tio2 ◽  
X Ray ◽  
Infra Red ◽  
Scanning Electron

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.

Infra-Red Reflectance Microscopy (IRRM) for Daisy Chain Flip Chip Device Failure Analysis

2004 ◽  
Author(s):  
Carlo Grilletto ◽  
Steve Hsiung ◽  
Andrew Komrowski ◽  
John Soopikian ◽  
Daniel J.D. Sullivan ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Flip Chip ◽  
State Of The Art ◽  
Failure Mechanisms ◽  
Simple Metal ◽  
X Ray ◽  
Infra Red ◽  
Cause Of Failure ◽  
Reflectance Microscopy ◽  
Ir Emission

Abstract This paper describes a method to "non-destructively" inspect the bump side of an assembled flip-chip test die. The method is used in conjunction with a simple metal-connecting "modified daisy chain" die and makes use of the fact that polished silicon is transparent to infra-red (IR) light. The paper describes the technique, scope of detection and examples of failure mechanisms successfully identified. It includes an example of a shorting anomaly that was not detectable with the state of the art X-ray equipment, but was detected by an IR emission microscope. The anomalies, in many cases, have shown to be the cause of failure. Once this has been accomplished, then a reasonable deprocessing plan can be instituted to proceed with the failure analysis.

Interaction of ditertiary phosphines with phenyl- and 1-naphthyldithiocarbamatonickel(II)

1985 ◽  
Vol 50 (6) ◽  
pp. 1383-1390
Author(s):  
Aref A. M. Aly ◽  
Ahmed A. Mohamed ◽  
Mahmoud A. Mousa ◽  
Mohamed El-Shabasy
Keyword(s):  
Thermal Analysis ◽  
Powder Diffraction ◽  
Spin Structure ◽  
Magnetic Measurements ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
X Ray ◽  
Square Planar

The synthesis of the following mixed ligand complexes is reported: [Ni(phdtc)2(dpm)2], [Ni(phdtc)2(dpe)2], [Ni(phdtc)2(dpp)3], [Ni(1-naphdtc)2(dpm)2], [Ni(1-naphdtc)2], and [Ni(1-naphdtc)2(dpp)2], where phdtc = PhNHCSS-, 1-naphdtc = 1-NaPhNHCSS-, dpm = Ph2PCH2PPh2, dpe = Ph2P(CH2)2PPh2, and dpp = Ph2P(CH2)3PPh2. The complexes are characterised by microanalysis, IR and UV-Vis spectra, magnetic measurements, conductivity, X-ray powder diffraction, and thermal analysis. All the mixed ligand complexes are diamagnetic, and thus a square-planar or square-pyramidal (low-spin) structure was proposed for the present complexes.

Ten-Vertex Polyhedral Monocarbaborane Chemistry. The Novel High-Yield Formation of the Ten-Vertex closo Compound [6-(PMe2Ph)-closo-1-CB9H9] from the Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11]

1993 ◽  
Vol 58 (12) ◽  
pp. 2924-2935 ◽  
Author(s):  
Jane H. Jones ◽  
Bohumil Štíbr ◽  
John D. Kennedy ◽  
Mark Thornton-Pett
Keyword(s):  
Nmr Spectroscopy ◽  
Diffraction Analysis ◽  
High Yield ◽  
Monoclinic Space Group ◽  
The Novel ◽  
X Ray Diffraction ◽  
Metal Centre ◽  
X Ray ◽  
Yield Formation ◽  
Boiling Toluene

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.

scholarly journals Some Novel Cobalt Diphenylphosphine Complexes: Synthesis, Characterization, and Behavior in the Polymerization of 1,3-Butadiene

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4067
Author(s):  
Giovanni Ricci ◽  
Giuseppe Leone ◽  
Giorgia Zanchin ◽  
Benedetta Palucci ◽  
Alessandra Forni ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
And Behavior

Some novel cobalt diphenylphosphine complexes were synthesized by reacting cobalt(II) chloride with (2-methoxyethyl)diphenylphosphine, (2-methoxyphenyl)diphenylphosphine, and 2-(1,1-dimethylpropyl)-6-(diphenylphosphino)pyridine. Single crystals suitable for X-ray diffraction studies were obtained for the first two complexes, and their crystal structure was determined. The novel compounds were then used in association with methylaluminoxane (MAO) for the polymerization of 1,3-butadiene, and their behavior was compared with that exhibited in the polymerization of the same monomer by the systems CoCl2(PnPrPh2)2/MAO and CoCl2(PPh3)2/MAO. Some significant differences were observed depending on the MAO/Co ratio used, and a plausible interpretation for such a different behavior is proposed.

A study on using expanded perlite with hydroxyapatite: Reinforced bio-composites

2021 ◽  
pp. 095441192199656
Author(s):  
Erdoğan Karip ◽  
Mehtap Muratoğlu
Keyword(s):  
Body Fluid ◽  
Xrd Analysis ◽  
Cold Isostatic Pressing ◽  
Expanded Perlite ◽  
X Ray Diffraction ◽  
Pressing Method ◽  
X Ray ◽  
Infra Red ◽  
Ft Ir

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.

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