The Solid Solution CeAuIn1–xMgx – Structure, Magnetic Properties and Specific Heat Data

2006 ◽  
Vol 61 (5) ◽  
pp. 495-502 ◽  
Author(s):  
Sudhindra Rayaprol ◽  
Birgit Heying ◽  
Rainer Pöttgen
Keyword(s):  
Solid Solution ◽  
Fermi Liquid ◽  
Induction Furnace ◽  
Magnetic Ordering ◽  
Magnesium Concentration ◽  
Crystal Data ◽  
Specific Heat Data ◽  
X Ray ◽  
The Difference ◽  
Heat Data

Four different samples of the solid solution CeAuIn1−xMgx with x = 0.2, 0.4, 0.6, and 0.8 have been prepared from the elements in sealed tantalum tubes in an induction furnace. The samples were characterized through X-ray powder and single crystal data: ZrNiAl type, P6̅2m, Z = 3, a = 774.54(7), c = 420.32(10) pm, wR2 = 0.0203, 395 F2 values, 15 variables for CeAuIn0.871Mg0.129, a = 775.25(7), c = 419.36(10) pm, wR2 = 0.0488, BASF = 0.10(1), 397 F2 values, 16 variables for CeAuIn0.640Mg0.360, a = 774.62(7), c = 420.13(10) pm, wR2 = 0.0435, 376 F2 values, 15 variables for CeAuIn0.445Mg0.555, a = 773.80(11), c = 420.82(8) pm, wR2 = 0.0415, 392 F2 values, 15 variables for CeAuIn0.228Mg0.772. The lattice parameters show no pronounced changes within the solid solution. The largest shift occurs for the x parameter of the mixed occupied In/Mg positions. Due to the difference in size, the trigonal prisms around the Au1 atoms at the origin become smaller with an increasing content of magnesium. The In/Mg-In/Mg distances decrease from 334.5 (CeAuIn0.871Mg0.129) to 328.3 (CeAuIn0.228Mg0.772) pm, and consequently one observes also shorter bonds to the Au1 atoms with an increasing content of magnesium concentration. Susceptibility measurements reveal trivalent cerium for all CeAuIn1−xMgx compounds, with no evidence sign of magnetic ordering down to 2 K. The disorder created by chemical substitution destroys the longrange magnetic ordering which can be attributed to the triggering of non Fermi-liquid (NFL) like behavior.

Curie temperature adjustment in the solid solution Gd1–x Y x PtMg

2021 ◽  
Vol 76 (9) ◽  
pp. 503-509
Author(s):  
Maximilian Kai Reimann ◽  
Rainer Pöttgen
Keyword(s):  
Solid Solution ◽  
Curie Temperature ◽  
Induction Furnace ◽  
Magnetic Ordering ◽  
Temperature Dependent ◽  
Structure Form ◽  
X Ray ◽  
Complete Solid Solution ◽  
Y Substitution ◽  
Ferromagnetic Ordering

Abstract GdPtMg and YPtMg (both crystallize with the ZrNiAl-type structure) form a complete solid solution Gd1–x Y x PtMg. Samples in x = 0.1 steps were synthesized from the elements in sealed tantalum ampoules in an induction furnace and characterized by Guinier powder patterns. The structures of four members of the solid solution were refined from single-crystal X-ray diffractometer data, confirming the mixed occupation of the Gd/Y site; however, without any indication for Gd/Y ordering. Temperature dependent magnetic susceptibility measurements reveal Curie-Weiss behavior for all samples and ferromagnetic ordering in the low-temperature regime. The Curie temperature drops linearly from 97.6 K for GdPtMg to 3.7 K for Gd0.1Y0.9PtMg. All samples are soft ferromagnets. The Gd/Y substitution is a suitable tool for adjusting magnetic ordering temperatures of gadolinium intermetallics over a broad temperature range.

Nanoporous Ni and Ni-Cu Fabricated by Dealloying

2009 ◽  
Vol 1228 ◽  
Author(s):  
Masataka Hakamada ◽  
Yasumasa Chino ◽  
Mamoru Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Solid Solution ◽  
Noble Metals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
The Difference ◽  
20 Nm ◽  
Good Workability ◽  
Scanning Electron

AbstractMetallic nanoporous architecture can be spontaneously attained by dealloying of a binary alloy. The nanoporous architecture can be often fabricated in noble metals such as Au and Pt. In this study, nanoporous Ni, Ni-Cu are fabricated by dealloying rolled Ni-Mn and Cu-Ni-Mn alloys, respectively. Unlike conventional Raney nickel composed of brittle Ni-Al or Cu-Al intermetallic compounds, the initial alloys had good workability probably because of their fcc crystal structures. After the electrolysis of the alloys in (NH4)2SO4 aqueous solution, nanoporous architectures of Ni and Ni-Cu with pore and ligament sizes of 10–20 nm were confirmed by scanning electron microscopy and transmission electron microscopy. X-ray diffraction analyses suggested that Ni and Cu atoms form a homogeneous solid solution in the Ni-Cu nanoporous architecture. The ligament sizes of nanoporous Ni and Ni-Cu were smaller than that of nanoporous Cu, reflecting the difference between diffusivities of Ni and Cu at solid/electrolyte interface. Ni can reduce the pore and ligament sizes of resulting nanoporous architecture when added to initial Cu-Mn alloys.

scholarly journals Temperature-Independent Cuprate Pseudogap from Planar Oxygen NMR

2020 ◽  
Vol 5 (4) ◽  
pp. 66 ◽  
Author(s):  
Jakob Nachtigal ◽  
Marija Avramovska ◽  
Andreas Erb ◽  
Danica Pavićević ◽  
Robin Guehne ◽  
...  
Keyword(s):  
Fermi Liquid ◽  
Exchange Coupling ◽  
Cuprate Superconductors ◽  
Nmr Relaxation ◽  
Nuclear Relaxation ◽  
Specific Heat Data ◽  
Optimal Doping ◽  
Gap States ◽  
Shift Data ◽  
Heat Data

Planar oxygen nuclear magnetic resonance (NMR) relaxation and shift data from all cuprate superconductors available in the literature are analyzed. They reveal a temperature-independent pseudogap at the Fermi surface, which increases with decreasing doping in family-specific ways, i.e., for some materials, the pseudogap is substantial at optimal doping while for others it is nearly closed at optimal doping. The states above the pseudogap, or in its absence are similar for all cuprates and doping levels, and Fermi liquid-like. If the pseudogap is assumed exponential it can be as large as about 1500 K for the most underdoped systems, relating it to the exchange coupling. The pseudogap can vary substantially throughout a material, being the cause of cuprate inhomogeneity in terms of charge and spin, so consequences for the NMR analyses are discussed. This pseudogap appears to be in agreement with the specific heat data measured for the YBaCuO family of materials, long ago. Nuclear relaxation and shift show deviations from this scenario near Tc, possibly due to other in-gap states.

scholarly journals Coefficients of Thermal Expansion of Al- and Y-Substituted NaSICON Solid Solution Na3+2xAlxYxZr2−2xSi2PO12

Batteries ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 33 ◽  
Author(s):  
Sahir Naqash ◽  
Marie-Theres Gerhards ◽  
Frank Tietz ◽  
Olivier Guillon
Keyword(s):  
Solid Solution ◽  
Thermal Expansion ◽  
High Temperature ◽  
Sodium Content ◽  
Phase Changes ◽  
Central Metal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sodium Batteries ◽  
The Difference

Because of an increasing interest in NaSICON materials as electrolyte materials in all-solid state sodium batteries, their thermal expansion was investigated in this study. The thermal expansion coefficient (CTE) of the Al and Y-substituted NaSICON compositions Na3+2xAlxYxZr2−2xSi2PO12 with 0 ≤ x ≤ 0.3 was obtained by dilatometry and compared to the CTE derived from the lattice parameters using high-temperature X-ray diffraction. The difference in CTE obtained from techniques, the influence of sodium content and central metal cation on CTE, as well as other observations such as phase changes are described and rationalized.

The Solid Solution CeAuIn1-xMgx — Structure, Magnetic Properties and Specific Heat Data.

ChemInform ◽  
2006 ◽  
Vol 37 (35) ◽  
Author(s):  
Sudhindra Rayaprol ◽  
Birgit Heying ◽  
Rainer Poettgen
Keyword(s):  
Solid Solution ◽  
Magnetic Properties ◽  
Specific Heat ◽  
Specific Heat Data ◽  
Heat Data

scholarly journals The vibration spectrum and molecular configuration of cyclohexane

1947 ◽  
Vol 190 (1021) ◽  
pp. 245-256 ◽  
Keyword(s):  
Dipole Moment ◽  
Raman Spectrum ◽  
Vibration Spectrum ◽  
Vibration Frequencies ◽  
Specific Heat Data ◽  
Molecular Configuration ◽  
X Ray ◽  
Physical Evidence ◽  
Infra Red ◽  
Heat Data

The physical evidence for the structure of the cyclohexane molecule (X-ray, electron diffraction, dipole moment, vibration spectra) is all in favour of the ‘chair’ configuration. The twelve vibration frequencies for the carbon skeleton of this model have been calculated, using a simple valency force field. There are eight distinct frequencies, four being doubly degenerate. The two force constants are evaluated from two of the Raman frequencies and used to calculate the remaining six frequencies. Five of these frequencies are found to agree with the observed frequencies to within 4%, while the sixth frequency is too low to be observed conveniently in the infra-red and is forbidden in the Raman spectrum. The value calculated (206 cm. -1 ) for this sixth frequency is, however, consistent with the specific heat data. The selection rules are shown to be obeyed by the assigned frequencies. The value for the C-C stretching force constant, viz. 3⋅7 x 10 5 dynes/cm. is considerably lower than that for the same bond in ethane, viz. 4.5 x 10 5 dynes/cm., indicating a weakening of the C-C bond in cyclohexane relative to ethane.

Squares of gold atoms and linear infinite chains of Cd atoms as building units in the intermetallic phases REAu4Cd2 (RE=La–Nd, Sm) with YbAl4Mo2-type structure

2020 ◽  
Vol 75 (1-2) ◽  
pp. 73-82 ◽  
Author(s):  
Christian Paulsen ◽  
Theresa Block ◽  
Christopher Benndorf ◽  
Oliver Oeckler ◽  
Judith Bönnighausen ◽  
...  
Keyword(s):  
Single Crystal ◽  
Magnetic Ordering ◽  
Intermetallic Phases ◽  
Rare Earth Ions ◽  
Crystal Data ◽  
Temperature Dependent ◽  
X Ray ◽  
Trivalent Rare Earth ◽  
Diffraction Patterns ◽  
Infinite Linear

AbstractThe gold-rich intermetallic compounds REAu4Cd2 (RE = La–Nd, Sm) were synthesized from the elements in sealed tantalum ampoules. Their characterization by X-ray powder and single crystal data confirmed the tetragonal YbAl4Mo2 type, space group I4/mmm. The basic building units are Au4 squares (278 pm Au–Au in CeAu4Cd2) and infinite linear cadmium chains (275 pm Cd–Cd in CeAu4Cd2). We exemplarily studied the solid solution CeAu4+xCd2−x for x = 0–1 up to CeAu5Cd. Electron diffraction patterns on a CeAu5Cd sample confirm the single crystal data. They give no hint for complete gold-cadmium ordering. Temperature-dependent magnetic susceptibility measurements of CeAu4Cd2, CeAu5Cd, PrAu4Cd2 and NdAu4Cd2 show stable trivalent rare earth ions and give no hint for magnetic ordering above 3 K.

X-ray powder diffraction analysis of NiZnCuSn ferrite containing antimony

1995 ◽  
Vol 10 (2) ◽  
pp. 120-121 ◽  
Author(s):  
Zong-ming Jin ◽  
Ya-jie Chen ◽  
Zheng Jin
Keyword(s):  
Solid Solution ◽  
Diffraction Analysis ◽  
Diffraction Pattern ◽  
Powder Diffraction ◽  
Xrd Analysis ◽  
Crystallographic Data ◽  
Crystal Data ◽  
X Ray

Crystallographic data for Ni0.41Zn0.60Cu0.01Fe2.04−xSbxO4+δ (0.01≤x≤0.12) ferrites are significantly influenced by small additions of antimony. XRD analysis reveals that changes in crystal data for small Sb substitutions differ markedly from those for greater Sb substitutions. The differences are due to the contribution of the Sb ion. Complete crystal data for six solid solution compositions are reported. An X-ray powder diffraction pattern for Ni0.41Zn0.60Cu0.02Sn0.01Fe2.02Sb0.02O4+δ is given.

Magnetocaloric and Thermal Properties of Ho(Co1–xSix)2 Compounds

2007 ◽  
Vol 62 (7) ◽  
pp. 965-970 ◽  
Author(s):  
Vladimír Sechovský ◽  
Denys Vasylyev ◽  
Jan Prokleška
Keyword(s):  
Magnetic Field ◽  
Specific Heat ◽  
Magnetocaloric Effect ◽  
Magnetic Phase ◽  
Magnetic Ordering ◽  
Entropy Change ◽  
Specific Heat Data ◽  
Magnetic Refrigerant ◽  
Ordering Transition ◽  
Heat Data

Abstract The specific heat and thermal conductivity of HoCo2 and Ho(Co0.95Si0.05)2 were measured as functions of temperature in several constant magnetic fields up to 8 T. From a specific-heat data analysis the isothermal entropy change and the magnetocaloric effect (MCE) have been evaluated in a wide temperature range for several values of the applied magnetic field. The considerable values of the magnetocaloric effect in the vicinity of the magnetic ordering transition are qualifying both compounds as suitable for magnetic refrigeration purposes. The magnetic phase transition temperature (TC) increases from 77 K for HoCo2 to 103 K for Ho(Co0.95Si0.05)2 while the large MCE in the vicinity of TC is maintained, which demonstrates ways of tuning the operating temperatures of the magnetic refrigerant.

Tm4IrIn and Lu4PtIn – In4 tetrahedra embedded in RE 22 polyhedra

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Nataliya L. Gulay ◽  
Maximilian Kai Reimann ◽  
Yaroslav M. Kalychak ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Single Crystal ◽  
Induction Furnace ◽  
Magnetic Ordering ◽  
Type Structure ◽  
Crystal Chemical ◽  
X Ray ◽  
Structure Space ◽  
Thulium Atom

Abstract The rare earth-rich indides Tm4IrIn and Lu4PtIn were synthesized by reaction of the elements in sealed tantalum ampules in an induction furnace. Tm4IrIn (a = 1340.77(4) pm) and Lu4PtIn (a = 1338.0(1) pm) crystallize with the Gd4RhIn-type structure, space group F 4 ‾ 3 m $F‾{4}3m$ . The Lu4PtIn structure was refined from single crystal X-ray diffractometer data: wR = 0.0524, 517 F 2 values and 20 variables. The striking crystal chemical motif is the fcc packing of In4 tetrahedra with 318 pm In–In. The Lu4PtIn structure is closely related to the structures of Lu13Ni6In, Lu14Pd3In3 and Lu20Ir5In3 which all show icosahedral indium coordination and different condensation patterns that build up the indium substructure that consists of a dumbbell in Lu14Pd3In3 and a triangle in Lu20Ir5In3. The results of magnetic susceptibility measurements indicate Curie-Weiss paramagnetism for Tm4IrIn (7.76(1) µB per thulium atom) without magnetic ordering down to 2.5 K. Lu4PtIn is Pauli-paramagnetic.

Sign in / Sign up

Export Citation Format

Share Document