X-Ray Diffraction Studies on Magneto-Volume Effect and the First Order Phase Transition in Lu(Co1-xGax)2

2000 ◽  
Vol 69 (12) ◽  
pp. 4013-4017 ◽  
Author(s):  
Kohki Hayashi ◽  
Keisuke Tajima ◽  
Hidekazu Saito ◽  
Kazuaki Fukamichi
Keyword(s):  
Phase Transition ◽  
Order Phase Transition ◽  
Volume Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
First Order Phase Transition ◽  
First Order Phase

Structure and Phase Transition in (C2H5NH3)3Sb2Cl9 · (C2H5NH3)SbCl4 ; X-ray, DSC and Dielectric Studies

2000 ◽  
Vol 55 (5) ◽  
pp. 526-532 ◽  
Author(s):  
Maciej Bujak ◽  
Jacek Zaleski
Keyword(s):  
Phase Transition ◽  
The Other ◽  
Dielectric Studies ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
First Order ◽  
First Order Phase Transition ◽  
First Order Phase ◽  
Disorder Type

Abstract The structure of (C2H5NH3)3Sb2Cl9 • (C2H5NH3)SbCl4 at 295 K has been determined. The crystals are orthorhombic, space group Pna21 (a -16.925(3), b = 24.703(5), c = 7.956(2) Å, V = 3326.4(12) Å3 , Z = 4, dc= 2.018, dm= 2.01(1) Mg m-3). They consist of an anionic sublattice composed of two different polymeric zig-zag chains. One is built of Sb2Cl93- units (corner sharing octahedra) and the other one is made of corner sharing SbCl52-square pyramids. In the cavites between the polyanionic chains four non-equivalent ethylammonium cations are located. Three of them are disordered. The cations are connected to the anions by weak N-H...Cl hydrogen bonds. A first order phase transition of the order-disorder type was found at 274 K. It was studied by DSC, dielectric and X-ray diffraction methods. The mechanism of the phase transition is attributed to the ordering of at least one of the ethylammonium cations

Stress Analysis of Thin-Film SmS Using a Seemann- Bohlin Diffractometer

1989 ◽  
Vol 33 ◽  
pp. 153-159 ◽  
Author(s):  
Fergus E. Moore
Keyword(s):  
Thin Film ◽  
Phase Transition ◽  
Biaxial Stress ◽  
X Ray Diffraction ◽  
Crystalline Film ◽  
X Ray ◽  
First Order ◽  
First Order Phase Transition ◽  
Samarium Monosulfide ◽  
First Order Phase

AbstractX-ray diffraction is especially useful in analyzing the phase-transition response of thin-film SmS to strain impressed by the two-dimensional constraints of the substrate. A biaxial-stress model is applied and extended to a randomly-oriented crystalline film. The changes in macrostress, the compliance tensor and effective Poisson's ratio are evaluated near the hulk phase transition. An analysis of crystallite size and microstrain broadening is also presented including broadening effects due to biaxial macrostrain on the randomly-oriented crystallites. These results illustrate the effect of a constraining, biaxial-stress field on the unusual elastic character of samarium monosulfide. It is demonstrated that the thin-film geometry suppresses the first-order phase transition allowing only linear changes between the semiconducting and metallic states.

scholarly journals Gravitational wave signals of dark matter freeze-out

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Danny Marfatia ◽  
Po-Yan Tseng
Keyword(s):  
Phase Transition ◽  
Dark Matter ◽  
Gravitational Waves ◽  
Order Phase Transition ◽  
First Order ◽  
Stochastic Background ◽  
First Order Phase Transition ◽  
Relic Abundance ◽  
First Order Phase ◽  
Freeze Out

Abstract We study the stochastic background of gravitational waves which accompany the sudden freeze-out of dark matter triggered by a cosmological first order phase transition that endows dark matter with mass. We consider models that produce the measured dark matter relic abundance via (1) bubble filtering, and (2) inflation and reheating, and show that gravitational waves from these mechanisms are detectable at future interferometers.

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