Thermally Induced Modifications and Phase Transformations of Red Coral Mg-Calcite Skeletons from Infrared Spectroscopy and High Resolution Synchrotron Powder Diffraction Analyses

2015 ◽  
Vol 15 (8) ◽  
pp. 3690-3706 ◽  
Author(s):  
Nicole Floquet ◽  
Daniel Vielzeuf ◽  
Daniel Ferry ◽  
Angèle Ricolleau ◽  
Vasile Heresanu ◽  
...  
2013 ◽  
Vol 25 (11) ◽  
pp. 2227-2242 ◽  
Author(s):  
Boris Bouchevreau ◽  
Charlotte Martineau ◽  
Caroline Mellot-Draznieks ◽  
Alain Tuel ◽  
Matthew R. Suchomel ◽  
...  

2012 ◽  
Vol 68 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Denis Orosel ◽  
Robert E. Dinnebier ◽  
Vladislav A. Blatov ◽  
Martin Jansen

A quenchable new high-pressure–high-temperature modification of antimony(III) oxide, γ-Sb2O3, has been obtained at hydrostatic pressures of 9–11 GPa and temperatures of 573–773 K. Its crystal structure has been determined from high-resolution synchrotron powder diffraction data. γ-Sb2O3 consists of three-dimensionally cross-linked infinite chains of SbO3 E units (E = lone pair) with the chains forming tetragonal rod-packing. The underlying topology of γ-Sb2O3 (3,3T8) is found very rarely in inorganic structures; it is realised only for the polyanion [Si4O4N6]10− that occurs in the Ce4(Si4O4N6)O structure type. The structural relation to the two previously known polymorphs of Sb2O3 at ambient pressure, valentinite and senarmontite is discussed.


2016 ◽  
Vol 28 (14) ◽  
pp. 5172-5172
Author(s):  
Boris Bouchevreau ◽  
Charlotte Martineau ◽  
Caroline Mellot-Draznieks ◽  
Julien Dutour ◽  
Alain Tuel ◽  
...  

ChemInform ◽  
2013 ◽  
Vol 44 (34) ◽  
pp. no-no
Author(s):  
Boris Bouchevreau ◽  
Charlotte Martineau ◽  
Caroline Mellot-Draznieks ◽  
Alain Tuel ◽  
Matthew R. Suchomel ◽  
...  

2004 ◽  
Vol 37 (5) ◽  
pp. 786-790 ◽  
Author(s):  
Masatomo Yashima ◽  
Masahiko Tanaka

Accurate crystal structure analysis at high temperatures is an important challenge in science and technology. A new electric furnace for the measurement of high-resolution (δd/d= 0.03%) synchrotron radiation powder diffraction profiles from materials at high temperatures (up to 1900 K in air) has been designed and fabricated. This furnace consists of a ceramic refractory with MoSi2heaters, an aluminium body cooled by flowing water, and a sample stage with a spinner and a controller for sample-height adjustment.In situsynchrotron powder diffraction measurement for a calcium titanate perovskite specimen at 1674 K has been performed using the furnace at beamline 3A of the Photon Factory. The electron density distribution of the cubic perovskite at 1674 K was successfully obtained using a combination of Rietveld refinement, the maximum-entropy method (MEM) and MEM-based pattern-fitting techniques. The Ti atoms exhibit covalent bonding with the O atoms in the cubic CaTiO3perovskite at this temperature, while the Ca atoms are ionic. These results indicate that the new furnace yields high-quality data for accurate crystal structure analysis.


1991 ◽  
Vol 52 (10) ◽  
pp. 1235-1241 ◽  
Author(s):  
Hermann Gies ◽  
Bernd Marler ◽  
Colin Fyfe ◽  
George Kokotailo ◽  
Y. Feng ◽  
...  

2003 ◽  
Vol 36 (2) ◽  
pp. 286-294 ◽  
Author(s):  
O. Masson ◽  
E. Dooryhée ◽  
A. N. Fitch

An accurate method for synthesizing the instrumental line profile of high-resolution synchrotron powder diffraction instruments is presented. It is shown that the instrumental profile can be modelled by the convolution of four physical aberration functions: the equatorial intensity distribution, the monochromator and analyser transfer functions, and the axial divergence aberration function. Moreover, each equatorial aberration is related to an angle-independent function by a scale transform factor. The principles of the instrument line-profile calculation are general. They are applied in the case of the angle-dispersive powder X-ray diffraction beamline BM16 at the ESRF. The effects of each optical element on the overall instrument profile are discussed and the importance of the quality of the different optical elements of the instrument is emphasized. Finally, it is shown that the high resolution combined with the precise modelling of the instrument profile shape give access to a particle size as large as 3 µm.


2020 ◽  
Vol 27 (3) ◽  
pp. 616-624 ◽  
Author(s):  
Shogo Kawaguchi ◽  
Michitaka Takemoto ◽  
Hideki Tanaka ◽  
Shotaro Hiraide ◽  
Kunihisa Sugimoto ◽  
...  

A gas- and vapour-pressure control system synchronized with the continuous data acquisition of millisecond high-resolution powder diffraction measurements was developed to study structural change processes in gas storage and reaction materials such as metal organic framework compounds, zeolite and layered double hydroxide. The apparatus, which can be set up on beamline BL02B2 at SPring-8, mainly comprises a pressure control system of gases and vapour, a gas cell for a capillary sample, and six one-dimensional solid-state (MYTHEN) detectors. The pressure control system can be remotely controlled via developed software connected to a diffraction measurement system and can be operated in the closed gas and vapour line system. By using the temperature-control system on the sample, high-resolution powder diffraction data can be obtained under gas and vapour pressures ranging from 1 Pa to 130 kPa in temperatures ranging from 30 to 1473 K. This system enables one to perform automatic and high-throughput in situ X-ray powder diffraction experiments even at extremely low pressures. Furthermore, this developed system is useful for studying crystal structures during the adsorption/desorption processes, as acquired by millisecond and continuous powder diffraction measurements. The acquisition of diffraction data can be synchronized with the control of the pressure with a high frame rate of up to 100 Hz. In situ and time-resolved powder diffraction measurements are demonstrated for nanoporous Cu coordination polymer in various gas and vapour atmospheres.


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