Texture of NiGe(Sn) on Ge(100) and its evolution with Sn content

2021 ◽  
Vol 54 (5) ◽  
pp. 1306-1316
Author(s):  
Andrea Quintero ◽  
Patrice Gergaud ◽  
Tra Nguyen-Thanh ◽  
Jean-Michel Hartmann ◽  
Vincent Reboud ◽  
...  
Keyword(s):  
The Other ◽  
X Ray Diffraction ◽  
Rich Phase ◽  
X Ray ◽  
Pole Figures ◽  
Out Of Plane ◽  
Diffraction Peaks ◽  
The Impact ◽  
Plane Diffraction

The texture of the Ni monostanogermanide phase on a Ge(100) substrate was evaluated during a solid-state reaction, with a focus on the impact of Sn addition. Complementary X-ray diffraction analyses involving in situ X-ray diffraction, in-plane reciprocal space maps (RSMs) and pole figures were used to that end. A sequential growth of the phases for the Ni/Ge(Sn) system was found. An Ni-rich phase formed first, followed by the NiGe(Sn) phase. The NiGe and NiGe(Sn) layers were polycrystalline with different out-of-plane orientations. The number of out-of-plane diffraction peaks decreased with the Sn content, while the preferred orientation changed. In-plane RSM analyses confirmed these results. Sn addition modified the out-of-plane and in-plane orientations. Pole figure analysis revealed that numerous epitaxial texture components were present for the Ni/Ge system, while Sn addition reduced the number of epitaxial texture components. On the other hand, segregated Sn crystallized with an epitaxial alignment with the Ge substrate underneath.

Ni/GeSn solid-state reaction monitored by combined X-ray diffraction analyses: focus on the Ni-rich phase

2018 ◽  
Vol 51 (4) ◽  
pp. 1133-1140 ◽  
Author(s):  
Andrea Quintero ◽  
Patrice Gergaud ◽  
Joris Aubin ◽  
Jean-Michel Hartmann ◽  
Vincent Reboud ◽  
...  
Keyword(s):  
Solid State ◽  
Low Temperature ◽  
Solid State Reaction ◽  
Metastable Phase ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Rich Phase ◽  
X Ray ◽  
Pole Figures

The Ni/Ge0.9Sn0.1 solid-state reaction was monitored by combining in situ X-ray diffraction, in-plane reciprocal space map measurements and in-plane pole figures. A sequential growth was shown, in which the first phase formed was an Ni-rich phase. Then, at 518 K, the mono-stanogermanide phase Ni(Ge0.9Sn0.1) was observed. This phase was stable up to 873 K. Special attention has been given to the nature and the crystallographic orientation of the Ni-rich phase obtained at low temperature. It is demonstrated, with in-plane pole figure measurements and simulation, that it was the ∊-Ni5(Ge0.9Sn0.1)3 metastable phase with a hexagonal structure.

PHASE TRANSITION IN LAYERED PEROVSKITE LIKE MANGANATE Ca3Mn2O7 UNDER HIGH PRESSURE

2001 ◽  
Vol 15 (18) ◽  
pp. 2491-2497 ◽  
Author(s):  
J. L. ZHU ◽  
L. C. CHEN ◽  
R. C. YU ◽  
F. Y. LI ◽  
J. LIU ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Diamond Anvil Cell ◽  
The Other ◽  
Layered Perovskite ◽  
X Ray Diffraction ◽  
Two Phase ◽  
X Ray ◽  
Diamond Anvil

In situ high pressure energy dispersive X-ray diffraction measurements on layered perovskite-like manganate Ca 3 Mn 2 O 7 under pressures up to 35 GPa have been performed by using diamond anvil cell with synchrotron radiation. The results show that the structure of layered perovskite-like manganate Ca 3 Mn 2 O 7 is unstable under pressure due to the easy compression of NaCl-type blocks. The structure of Ca 3 Mn 2 O 7 underwent two phase transitions under pressures in the range of 0~35 GPa. One was at about 1.3 GPa with the crystal structure changing from tetragonal to orthorhombic. The other was at about 9.5 GPa with the crystal structure changing from orthorhombic back to another tetragonal.

scholarly journals Lanthanoid Complexes Supported by Retro-Claisen Condensation Products of β-Triketonates

2018 ◽  
Author(s):  
Laura Abad Galán ◽  
Alexandre N. Sobolev ◽  
Eli Zysman-Colman ◽  
Mark Ogden ◽  
Massimiliano Massi
Keyword(s):  
Chelating Ligands ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
Claisen Condensation ◽  
X Ray ◽  
Condensation Products ◽  
Complexation Reactions ◽  
The Impact ◽  
Low Solubility

<i>β</i>-Triketonates have been recently used as chelating ligands for lanthanoid ions, presenting unique structures varying from polynuclear assemblies to polymers. In an effort to overcome low solubility of the complexes of tribenzoylmethane, four <i>β</i>-triketones with higher lipophilicity were synthesised. Complexation reactions were performed for each of these molecules using different alkaline bases in alcoholic media. X-ray diffraction studies suggested that the ligands were undergoing decomposition under the reaction conditions. This is proposed to be caused by <i>in situ</i>retro-Claisen condensation reactions, consistent with two examples that have been reported previously. The lability of the lanthanoid cations in the presence of a varying set of potential ligands gave rise to structures where one, two, or three of the molecules involved in the retro-Claisen condensationreaction were linked to the lanthanoid centres. These results, along with measurements of ligand decomposition in the presence of base alone, suggest that using solvents of lower polarity will mimimise the impact of the retro-Claisen condensation in these complexes. <br>

scholarly journals Intermetallic/Ceramic Composites Synthesized from Al–Ni–Ti Combustion with B4C Addition

Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 873
Author(s):  
Chun-Liang Yeh ◽  
Chih-Yao Ke
Keyword(s):  
Combustion Velocity ◽  
Ceramic Composites ◽  
The Other ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
Reaction Systems ◽  
X Ray ◽  
High Temperature Synthesis ◽  
In Situ Formation

The fabrication of intermetallic/ceramic composites by combustion synthesis in the mode of self-propagating high-temperature synthesis (SHS) was investigated in the Al–Ni–Ti system with the addition of B4C. Two reaction systems were employed: one was used to produce the composites of xNiAl–2TiB2–TiC with x = 2–7, and the other was used to synthesize yNi3Al–2TiB2–TiC with y = 2–7. The reaction mechanism of the Al–Ni–Ti system was strongly influenced by the presence of B4C. The reaction of B4C with Ti was highly exothermic, so the reaction temperature and combustion velocity decreased due to increasing levels of Ni and Al in the reactant mixture. The activation energies of Ea = 110.6 and 172.1 kJ/mol were obtained for the fabrication of NiAl- and Ni3Al-based composites, respectively, by the SHS reaction. The XRD (X-ray diffraction) analysis showed an in situ formation of intermetallic (NiAl and Ni3Al) and ceramic phases (TiB2 and TiC) and confirmed no reactions taking place between Ti and Al or Ni. The microstructure of the product revealed large NiAl and Ni3Al grains and small TiB2 and TiC particles. With the addition of TiB2 and TiC, the hardness of NiAl and Ni3Al was considerably increased and the toughness was also improved.

scholarly journals In Situ Observation of Stress Accumulation during Sub-Merged Arc Welding

2014 ◽  
Vol 996 ◽  
pp. 417-423 ◽  
Author(s):  
Arne Kromm ◽  
Thomas Kannengiesser
Keyword(s):  
Arc Welding ◽  
Large Scale ◽  
X Ray Diffraction ◽  
X Ray ◽  
Residual Stress State ◽  
Testing Facility ◽  
Large Scale Testing ◽  
The Impact ◽  
Stress Accumulation

Results obtained from laboratory tests mostly need to be verified under fabrication conditions in order to incorporate design specifics (joint configuration and restraint), which effect the residual stress state considerably. For this purpose, multi-pass sub merged arc welding was performed in a special large-scale testing facility. The impact of varying interpass temperatures could be proven in-situ by means of a pronounced stress accumulation during welding and subsequent heat treatment accompanied by stress determination using X-ray diffraction.

In Situ X-Ray Diffraction of an Arc Weld Showing the Phase Transformations of Ti and Fe as a Function of Position in the Weld Performed at a Synchrotron

1993 ◽  
Vol 37 ◽  
pp. 479-482 ◽  
Author(s):  
Joe Wong ◽  
J. W. Elmer ◽  
P. A. Waide ◽  
E. M. Larson
Keyword(s):  
Combustion Synthesis ◽  
Ferroelectric Material ◽  
Bragg Diffraction ◽  
Intermediate Species ◽  
X Ray Diffraction ◽  
Synchrotron Source ◽  
X Ray ◽  
Subsequent Phase ◽  
Diffraction Peaks

The synchrotron x-ray source provides a unique opportunity to observe many “in-situ” processes. The formation of the “short-lived” intermediate species, Ta2C, during the combustion synthesis of TaC, has been observed and reported by monitoring the Bragg diffraction peaks of the reactants and products, Similarly, the synthesis of the ferroelectric material, BaTiO3, and subsequent phase transfonnation from cubic to tetragonal have also been investigated. These experiments would not have been possible without the high incident x-ray flux available at a synchrotron source.

Compression and Compressibility Studies of Plutonium and a Plutonium-Gallium Alloy

1980 ◽  
Vol 24 ◽  
pp. 221-230 ◽  
Author(s):  
R. B. Roof
Keyword(s):  
Solid Solution ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Foils ◽  
Gallium Alloy

Two metal foils, one pure plutonium and the other being a solid solution of 6.5 a/o gallium In plutonium, were examined, in-situ, by X-ray diffraction techniques while under pressure. The purpose was to determine the compression and compressibility of these materials as a function of pressure and to identify the products of any transformation that may occur due to the action of applied pressures.

1,1-Carboboration Reactions of Strongly Electrophilic 2-Borylethyl Thioethers

2014 ◽  
Vol 69 (11-12) ◽  
pp. 1357-1364 ◽  
Author(s):  
Christina Eller ◽  
Bastian Billmann ◽  
Constantin G. Daniliuc ◽  
Gerald Kehr ◽  
Gerhard Erker
Keyword(s):  
Carbon Atom ◽  
Addition Product ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hb C

Abstract The RSCH2CH2B(C6F5)2 boranes 3a (R=Ph) and 3b (R=Et) were in situ generated by HB(C6F5)2 hydroboration of the respective vinylthioethers. Their treatment with R1-C≡C- SiMe3 acetylenes resulted in clean 1,1-carboboration to give the respective RSCH2CH2-substituted alkenylboranes 4 (3 examples). Likewise, the reagents 3 underwent 1,1-carboboration with the acetylenes Ar2P-C≡C-SiMe3 to give the tetrasubstituted alkenylboranes 6, featuring a geminal pair of RSCH2CH2=B(C6F5)2 substituents at one carbon atom and the Me3Si=PAr2 pair at the other (3 examples). The compounds 6 feature an internal B···P interaction. The conceptually related Mes2PCH2CH2B(C6F5)2 borane (2) does not undergo 1,1-carboboration with ArS-C≡C-SiMe3 but forms the 1,2-P=B-FLP addition product 7 to the acetylene instead. Compounds 4a, 4c, 6a, and 7 were characterized by X-ray diffraction.

scholarly journals Probing the Dehydroxylation of Kaolinite and Halloysite by In Situ High Temperature X-ray Diffraction

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 480
Author(s):  
Imane Daou ◽  
Gisèle Lecomte-Nana ◽  
Nicolas Tessier-Doyen ◽  
Claire Peyratout ◽  
Maurice Gonon ◽  
...  
Keyword(s):  
High Temperature ◽  
Coefficient Of Thermal Expansion ◽  
Tape Casting ◽  
Treatment Temperature ◽  
Structure Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pole Figures ◽  
Basal Distance

Textured kaolinite and halloysite-based materials were shaped by tape casting in order to promote the alignment of clay particles along the tape casting direction and to investigate the structure evolution of these phyllosilicates during the dehydroxylation process. The crystallinity indexes HI and R2 of the starting kaolins (KRG and KCS) were determined and appeared close to values found for the well-ordered reference kaolin KGa-1b. The halloysite clay exhibited trimodal grain size distribution and tended to be less textured than KRG and KCS according to the (002) pole figures performed on green tapes. The constant heating rate derived kinetic parameters matched the expected range. We followed the dehydroxylation of kaolinite and halloysite through in situ high-temperature X-ray diffraction measurements at the ESRF synchrotron radiation source on the D2AM beamline. The dehydroxylation of these kaolinite and halloysite occurred between 425 °C and 675 °C for KRG and KCS and from 500 °C to 650 °C for halloysite. In addition, the evolution of the basal distance of kaolinite regarding the heat treatment temperature confirmed that the dehydroxylation process occurred in three steps: delamination, dehydroxylation, and formation of metakaolinite. The calculated coefficient of thermal expansion (CTE) along the c axe values were close to 17 × 10−6 °C−1 for kaolinite (KCS and KRG) and 14 × 10−6 °C−1 for halloysite.

scholarly journals Reduced roughness for improved mobility in benzodipyrrolidone-based, n-type OFETS

2014 ◽  
Vol 2 (41) ◽  
pp. 8822-8828 ◽  
Author(s):  
J. W. Rumer ◽  
S. Rossbauer ◽  
M. Planells ◽  
S. E. Watkins ◽  
T. D. Anthopoulos ◽  
...  
Keyword(s):  
Solid State ◽  
Electron Mobility ◽  
Film Surface ◽  
The Other ◽  
Surface Topology ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bottom Contact ◽  
Out Of Plane

Six phenyl-flanked benzodipyrrolidone-based copolymers are designed, synthesised and characterised. Three exhibit backbone in-plane curvature or out-of-plane twisting, while the other three remain planar and co-linear. While the first three appear less crystalline by X-ray diffraction, they afford a smoother solid-state film surface topology and increased electron mobility in top-gate, bottom-contact OFETs.

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