Synthesis of New Nitrides Using Solid State Oxide Precursors

1993 ◽  
Vol 327 ◽  
Author(s):  
Joel D. Houmes ◽  
David S. Bem ◽  
Hans-Conrad Zur Loye
Keyword(s):  
Solid State ◽  
Magnetic Measurements ◽  
Reaction Times ◽  
Magnetic Ordering ◽  
Beta Phase ◽  
Alpha Phase ◽  
Transition Metal Nitrides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Trigonal Prismatic Coordination

AbstractSeveral novel transition metal nitrides were synthesized via ammonolysis of solid state oxide precursors at temperatures ranging from 700°C-900°C and reaction times ranging from 12 hours to 4 days. Both intermetallic nitrides, Fe3Mo3N and Co3Mo3N, and ionic/covalent nitrides, FeWN2, MnWN2, Ta5N6 and Nb5N6, were prepared by this method. The products were characterized by powder X-ray diffraction and their structures were determined by powder X-ray Rietveld refinement. The intermetallic nitrides were found to be isostructural with the eta-carbide structure, Fe3W3C, while the ionic/covalent nitrides have layered structures, with metals in octahedral and trigonal prismatic coordination environments. Two polymorphs of the MnWN2 composition, α-MnWN2 and β-MnWN2, were isolated after ammonolysis at 700°C and 800°C, respectively. While the alpha phase can be converted into the beta phase by heating to 800°C under ammonia, annealing the beta phase at 700°C did not result in a structural transformation. Magnetic measurements show that FeWN2 orders antiferromagnetically at 45K. The magnetic ordering temperature was confirmed by M6ssbauer spectroscopy. All the other nitrides were paramagnetic down to 5K. Conductivity measurements show that FeWN2 and MnWN2 are metallic.

Structures of New Nitrides Prepared using Solid Oxide Precursors

1995 ◽  
Vol 410 ◽  
Author(s):  
Joel D. Houmes ◽  
David S. Bem ◽  
Hans-Conrad Zur Loye
Keyword(s):  
Solid State ◽  
Transition Metal ◽  
Transition Metal Dichalcogenides ◽  
Reaction Times ◽  
Solid Oxide ◽  
Metal Nitrides ◽  
Transition Metal Nitrides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Dichalcogenides

ABSTRACTSeveral novel transition metal nitrides and oxynitrides were synthesized via ammonolysis of solid state oxide precursors at temperatures ranging from 700°C-900°C and reaction times ranging from 12 hours to 4 days. The products were characterized by powder X-ray diffraction and their structures were determined by powder X-ray Rietveld refinement. The relationships between the structures of these nitrides and oxynitrides, and their similarity to the structures of the transition metal dichalcogenides, is discussed.

Structural, dielectric and magnetic properties of Pr-, Tb- and Dy-doped (Bi0.95RE0.05)(Fe0.95Mn0.05)O3 ceramics synthesized by solid-state reaction method

2013 ◽  
Vol 03 (04) ◽  
pp. 1350033 ◽  
Author(s):  
Radheshyam Rai ◽  
Shweta Thakur ◽  
M. A. Valente ◽  
Andrei L. Kholkin
Keyword(s):  
Magnetic Properties ◽  
Solid State ◽  
Solid State Reaction ◽  
Magnetic Measurements ◽  
Ferroelectric Properties ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Ceramic Samples

The multiferroic ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3 (where RE = Pr , Tb and Dy ) has been synthesized using solid-state reaction technique. Effects of Pr , Tb and Dy substitution on the structure, electrical and ferroelectric properties of ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3 samples have been studied by performing X-ray diffraction, dielectric measurements and magnetic measurements. The crystal structure of the ceramic samples have a monoclinic phase. The vibrating sample magnetometer (VSM) measurement shows a significant change in the magnetic properties of Pr -, Tb - and Dy -doped ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3. It is seen that coercive field (Hc) and remanent magnetization (Mr) increases for Pr but decreases for Dy and Tb .

scholarly journals Structural characterization of liquid phase sintered silicon carbide by high-resolution X-ray diffractometry

Cerâmica ◽  
2005 ◽  
Vol 51 (318) ◽  
pp. 168-172 ◽  
Author(s):  
C. A. Kelly ◽  
P. A. Suzuki ◽  
S. Ribeiro ◽  
S. Kycia
Keyword(s):  
Silicon Carbide ◽  
High Resolution ◽  
Mixed Oxide ◽  
Beta Phase ◽  
Alpha Phase ◽  
X Ray Diffraction ◽  
Solid Solution Formation ◽  
X Ray ◽  
Synchrotron Light

Silicon carbide (SiC) was sintered using two different additives: AlN-Y2O3 or AlN-CRE2O3. CRE2O3 is a mixed oxide formed by Y2O3 and rare-earth oxides. The crystalline structures of the phases were analyzed by high-resolution X-ray diffraction using synchrotron light source. The results of the Rietveld refinement of the mixed oxide show a solid solution formation. In both silicon carbide samples prepared using AlN-Y2O3 or AlN-CRE2O3 3C (beta-phase) and 6H (alpha-phase) polytypes were found. The structural and microstructural results for both samples were similar. This is an indication of the viability of the use of CRE2O3 in substitution for Y2O3 as additive to obtain dense materials.

Magnetic and Structural Properties of Nanocomposite ZnO-Fe3O4 Films Prepared by Solid-State Synthesis

2014 ◽  
Vol 215 ◽  
pp. 158-162
Author(s):  
Liudmila E. Bykova ◽  
V.G. Myagkov ◽  
I.A. Tambasov ◽  
O.A. Bayukov ◽  
Victor S. Zhigalov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Solid State ◽  
Photoelectron Spectroscopy ◽  
Magnetic Measurements ◽  
X Ray Diffraction ◽  
Simple Method ◽  
Physical Methods ◽  
X Ray ◽  
Scanning Electron

A simple method for obtaining ZnO-Fe3O4 nanocomposites using solid-state reaction Zn + 3Fe2O3 ZnO + 2Fe3O4 is suggested. An analysis of the characteristics and properties of ZnO-Fe3O4 nanocomposites was carried out by a combination of structural and physical methods (X-ray diffraction, scanning electron microscopy, photoelectron spectroscopy, Mössbauer measurements, X-ray fluorescent analysis, and magnetic measurements). The magnetization of the hybrid ZnO-Fe3O4 films is equal to 440 emu/cm3. The resulting Fe3O4 nanoparticles are surrounded by a ZnO shell and have sizes ranging between 20 and 40 nm.

Synthesis of Ferromagnetic Germanides in 40Ge/60Mn Films: Magnetic and Structural Properties

2014 ◽  
Vol 215 ◽  
pp. 167-172
Author(s):  
Victor G. Myagkov ◽  
A.A. Matsunin ◽  
Y.L. Mikhlin ◽  
Victor S. Zhigalov ◽  
Liudmila E. Bykova ◽  
...  
Keyword(s):  
Solid State ◽  
Curie Temperature ◽  
Photoelectron Spectroscopy ◽  
Magnetic Measurements ◽  
Atomic Ratio ◽  
Photoelectron Spectra ◽  
Solid State Reactions ◽  
Ferromagnetic Phase ◽  
X Ray Diffraction ◽  
X Ray

Solid-state reactions between Ge and Mn films are systematically examined using X-ray diffraction, photoelectron spectroscopy and magnetic measurements. The films have a nominal atomic ratio Ge:Mn = 40:60 and are investigated at temperatures from 50 to 500 °С. It is established that after annealing at ~120 °С, the ferromagnetic Mn5Ge3 phase is the first phase to form at the 40Ge/60Mn interface. Increasing the annealing temperature to 500 °С leads to the formation of the ferromagnetic phase with a Curie temperature TC ~ 360 K and magnetization MS ~ 140-200 emu/cc at room temperature. Analysis of X-ray diffraction patterns and the photoelectron spectra suggests that the increased Curie temperature and magnetization are related to the migration of C and O atoms into the Mn5Ge3 lattice and the formation of the Nowotny phase Mn5Ge3СxOy. The initiation temperature (~120 °С) of the Mn5Ge3 phase is the same both for solid-state reactions in Ge/Mn films, as well as for phase separation in GexMn1-x diluted semiconductors. We conclude that the synthesis of the Mn5Ge3 phase is the moving force for the spinodal decomposition of the GexMn1-x diluted semiconductors.

Fourfold Magnetic Anisotropy of CoPd Alloy, Obtained by Solid State Reactions in Epitaxal Pd/hcp-Сo and Pd/fcc-Co Bilayers

2015 ◽  
Vol 233-234 ◽  
pp. 571-574
Author(s):  
V.G. Myagkov ◽  
L.E. Bykova ◽  
V.S. Zhigalov ◽  
I.A. Tambasov ◽  
G.N. Bondarenko ◽  
...  
Keyword(s):  
Solid State ◽  
Magnetocrystalline Anisotropy ◽  
Magnetic Measurements ◽  
Anisotropy Constant ◽  
Solid State Reactions ◽  
Atomic Composition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Annealing Temperatures ◽  
Disordered Phase

The solid-state reaction between epitaxial hcp-Co (110) and fcc-Co (001) thin films and Pd layers was investigated at annealing temperatures between 250 and 650 °C using X-ray diffraction and magnetic measurements. No significant intermixing of the layers occurs at annealing temperatures below 400 °C. For the atomic composition 1Co:1Pd after annealing at 450 °C the disordered solid solution fcc-CoxPd1-x is formed on the Pd/hcp-Co (110) and Pd/fcc-Co (001) interfaces. Epitaxial relationships CoPd (110)〈-111〉 || MgO(001)〈100〉 and CoPd (001)〈100〉 || MgO(001)〈100〉 between the nucleated disordered phase CoPd and the substrate MgO(001) were determined for Pd/hcp-Co (110) and Pd/fcc-Co (001) bilayers, respectively. The first magnetocrystalline anisotropy constant of the disordered CoPd phase ​​K1CoPd = - (1.8 ± 0.4)·104 J/m3 for the (110) and (001) orientations was obtained.

Synthesis, Structure and Magnetic Properties of the Group IV Ternary Nitrides, AMN2 (A = Alkaline Earth Metal, M = Transition Metal)

1998 ◽  
Vol 547 ◽  
Author(s):  
Duncan H. Gregory ◽  
Marten G. Barker ◽  
Daniel J. Siddons ◽  
Peter P. Edwards ◽  
Marcin Slaski
Keyword(s):  
Transition Metal ◽  
Alkaline Earth ◽  
Magnetic Measurements ◽  
Earth Metal ◽  
Group Iv ◽  
Alkaline Earth Metal ◽  
Transition Metal Nitrides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nominal Stoichiometry

AbstractThe ternary transition metal nitrides of general formulation AMN2 (A = alkaline earth metal, M = transition metal) have been systematically studied. These compounds have been synthesised by high temperature solid state reaction from their component binary nitrides in sealed systems. The structures of these materials have been determined by powder X-ray diffraction (PXD) and two layered structure-types (α-NaFeO2-type and KCoO2-type) have been observed, thus far. Intriguingly, magnetic measurements performed on nitride samples indicate they may not be diamagnetic (d = 0, S = 0) as their nominal stoichiometry suggests.

Synthesis, structure, photoluminescent, optical and magnetic properties of a novel thulium p-hydroxybenzenesulfonate complex

2019 ◽  
Vol 234 (3) ◽  
pp. 177-182
Author(s):  
Rong-Hua Hu ◽  
Wen-Tong Chen ◽  
Jian-gen Huang
Keyword(s):  
Magnetic Susceptibility ◽  
Solid State ◽  
Diffuse Reflectance ◽  
Magnetic Measurements ◽  
Variable Temperature ◽  
X Ray Diffraction ◽  
Monoclinic System ◽  
X Ray ◽  
Elemental Analyses ◽  
Anti Stokes

Abstract A novel thulium p-hydroxybenzenesulfonate complex [Tm(C6H5O4S)2(H2O)6](C6H5O4S)·3H2O (1) was solvothermally synthesized and characterized by elemental analyses, photoluminescence, solid-state UV/vis diffuse reflectance, magnetic measurements and single-crystal X-ray diffraction. Complex 1 features an ionic structure with the thulium ion possessing a square antiprismatic geometry. Complex 1 crystallized in the monoclinic system with space group P21. Photoluminescent measurements with solid-state sample demonstrate that the anti-Stokes emission bands in the red/NIR spectral region 710 and 812 nm are observed from the Tm3+ 4f intrashell transitions from the 3F2,3 excited states to the 3H6 and 1G4 excited state to the 3H5 state, respectively. Solid-state UV/vis diffuse reflectance spectra of complex 1 show the existence of a wide optical band gap of 3.56 eV. Variable-temperature magnetic susceptibility and field dependence magnetization measurements are also studied and the magnetic susceptibility obeys the Curie-Weiss law (χm=c/(T−θ)) with the value C being of 8.6 K and a negative Weiss constant θ being of −0.2 K.

The Characterization Of Organic Charge Transfer Superconductors By Microreflectance Spectroscopy

1990 ◽  
Vol 48 (2) ◽  
pp. 272-273
Author(s):  
S. L. Hill ◽  
K. Krishnan ◽  
J. R. Ferraro
Keyword(s):  
Charge Transfer ◽  
Single Crystal ◽  
Beta Phase ◽  
Alpha Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Crystallography ◽  
A Value ◽  
Charge Transfer Salts

Certain classes of organic charge-transfer salts demonstrate superconducting behavior at liquid helium temperatures. Single crystal x-ray diffraction and infrared microreflectance analysis have been performed on several conducting systems to associate the nature of the crystalline structure with the electrical conductivity. The infrared spectrum for a single crystal salt exhibits absorptions which correlate with superconducting behavior.Discussion Williams and coworkers have performed x-ray Crystallography experiments to demonstrate the presence of an anion cavity between radical cation stacks- of bis(ethylenedithio)- tetrathiafulvalene (ET). The sulfur…sulfur interstack distance in a beta or kappa phase salt assumes a value less than the Vanderwaals distance and exhibit a superconducting (two dimensional) metal behavior (verified by Fermi surface calculations) at 1-20K. The structures of alpha and beta phase ET2I3 suggest the potential for several potential intermolecular interaction modes. It may be observed that the beta phase permits both interstack as well as H … X anionic interactions, whereas these interactions are less likely to occur in the alpha phase.

The Collagenic Molecular Structural Unit of Solid State Complexes

1971 ◽  
Vol 29 ◽  
pp. 478-479
Author(s):  
Kenneth M. Richter ◽  
John A. Schilling
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Structural Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Naoh Treatment

The structural unit of solid state collagen complexes has been reported by Porter and Vanamee via EM and by Cowan, North and Randall via x-ray diffraction to be an ellipsoidal unit of 210-270 A. length by 50-100 A. diameter. It subsequently was independently demonstrated by us in dog tendon, dermis, and induced complexes. Its detailed morphologic, dimensional and molecular weight (MW) aspects have now been determined. It is pear-shaped in long profile with m diameters of 57 and 108 A. and m length of 263 A. (Fig. 1, tendon, KMnO4 fixation, Na-tungstate; Fig. 2a, schematic of unit in long, C, and x-sectional profiles of its thin, xB, and bulbous, xA portions; Fig. 2b, tendon essentially unmodified by ether and 0.4 N NaOH treatment, Na-tungstate). The unit consists of a uniquely coild cable, c, of ṁ 22.9 A. diameter and length of 2580-3316 A. The cable consists of three 2nd-strands, s, each of m 10.6 A.

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