X-Ray Diffraction in the Electron Probe Microanalyzer

Author(s):  
B. H. Heise
2018 ◽  
Vol 74 (8) ◽  
pp. 917-922
Author(s):  
Hisanori Yamane ◽  
Keita Hiraka

Single crystals of the filled Ti2Ni-type Ti3Zn3O x η-phase (cubic, space group Fd\overline{3}m) having {111} facets were obtained by heating Ti, Zn and ZnO with a Bi flux. The lattice parameter of a single crystal prepared at 800°C was 11.4990 (2) Å, which is close to that of Ti3Zn3O∼0.5 (a = 11.502 Å), as reported by Rogl & Nowotny [Monatsh. Chem. (1977), 108, 1167–1180]. The occupancies of the O1 (16c) and O2 (8a) sites were 1 and 0.071 (12), respectively, and the composition of the crystal was determined to be Ti3Zn3O1.04. A single crystal from the sample prepared at 650°C had the same structure type, with a lattice parameter of 11.5286 (2) Å. However, O atoms were situated at a new 32e site in addition to the original 16c and 8a sites, and the Zn-atom positions were split in accordance with the new O-atom site. The chemical formula Ti3Zn3O1.27 determined by X-ray diffraction occupancy refinement agreed with the chemical composition obtained for the cross section of the single crystal determined with an electron probe microanalyzer.


1999 ◽  
Vol 14 (2) ◽  
pp. 447-455 ◽  
Author(s):  
U. Kolitsch ◽  
H. J. Seifert ◽  
T. Ludwig ◽  
F. Aldinger

In order to clarify inconsistencies in the literature and to verify assumed ternary solubilities, the phase equilibria in the Y2O3–Al2O3 –SiO2 system at 1600, 1400, and 1300 °C were experimentally determined using x-ray diffraction (XRD), scanning electron microscope with attached energy-dispersive detector system (SEM-EDX), and electron probe microanalyzer (EPMA). Six quasibinary phases were observed: Y4Al2O9 (YAM), YAlO3 (YAP), Y3Al5O12 (YAG), Y2SiO5, Y2Si2O7 (C and D modifications), and ˜3Al2O3· 2SiO2 (mullite). Y4Al2O9 forms an extended ternary solid solution with the formula Y4Al2(1-x)Si2xO9+x (x = 0 2 ˜0.31). The lowest ternary eutectic temperature was determined at 1371 ± 5 °C by high-temperature differential scanning calorimetry (DSC). The results were compared with previous data available for the Y2O3–Al2O3 –SiO2 system and with data for other RE2O3–Al2O3 –SiO2 (RE = rare earth element) systems.


Metals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 958 ◽  
Author(s):  
Cuiping Wang ◽  
Xianjie Zhang ◽  
Lingling Li ◽  
Yunwei Pan ◽  
Yuechao Chen ◽  
...  

The phase equilibria of the Co-Ti-Ta ternary system at 1000 °C, 1100 °C, and 1200 °C were experimentally investigated using an electron probe microanalyzer and X-ray diffraction. Experimental results show that: (1) No ternary compound exists in the studied isothermal sections; (2) the β(Ti) and β(Ta) phases form the continuous solid solution β(Ti,Ta) in the Ti-Ta side; (3) the solubility of Ta in the (αCo) is less than 5%; (4) the phases of Co2Ti(h) and γ-Co2Ta, Co2Ti(c) and β-Co2Ta form the continuous solid solutions Co2(Ta,Ti)(h) and Co2(Ta,Ti)(c), respectively.


1999 ◽  
Vol 5 (S2) ◽  
pp. 78-79
Author(s):  
C. Merlet ◽  
X. Llovet ◽  
F. Salvat

Studies of x-ray emission from thin films on substrates using an electron probe microanalyzer (EPMA) provide useful information on the characteristics of x-ray generation by electron beams. In this study, EPMA measurements of multilayered samples were performed in order to test and improve analytical and numerical models used for quantitative EPMA. These models provide relatively accurate results for samples consisting of layers with similar average atomic numbers, because of their similar properties regarding electron transport and x-ray generation. On the contrary, these models find difficulties to describe the process when the various layers have very different atomic numbers. In a previous work, we studied the surface ionization of thin copper films of various thicknesses deposited on substrates with very different atomic numbers. In the present communication, the study is extended to the case of multilayered specimens.The studied specimens consisted of thin copper films deposited on a carbon layer which, in turn, was placed on a variety of single-element substrates, ranging from Be to Bi.


Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1028 ◽  
Author(s):  
M. Mashrur Zaman ◽  
Sytle M. Antao

This study investigates the crystal chemistry of monazite (APO4, where A = Lanthanides = Ln, as well as Y, Th, U, Ca, and Pb) based on four samples from different localities using single-crystal X-ray diffraction and electron-probe microanalysis. The crystal structure of all four samples are well refined, as indicated by their refinement statistics. Relatively large unit-cell parameters (a = 6.7640(5), b = 6.9850(4), c = 6.4500(3) Å, β = 103.584(2)°, and V = 296.22(3) Å3) are obtained for a detrital monazite-Ce from Cox’s Bazar, Bangladesh. Sm-rich monazite from Gunnison County, Colorado, USA, has smaller unit-cell parameters (a = 6.7010(4), b = 6.9080(4), c = 6.4300(4) Å, β = 103.817(3)°, and V = 289.04(3) Å3). The a, b, and c unit-cell parameters vary linearly with the unit-cell volume, V. The change in the a parameter is large (0.2 Å) and is related to the type of cations occupying the A site. The average <A-O> distances vary linearly with V, whereas the average <P-O> distances are nearly constant because the PO4 group is a rigid tetrahedron.


1982 ◽  
Vol 46 (341) ◽  
pp. 445-448 ◽  
Author(s):  
R. R. Harding ◽  
R. J. Merriman ◽  
P. H. A. Nancarrow

AbstractThe occurrence of three accessory minerals with significant rare earth contents in Tertiary acid rocks of St. Kilda is described. Allanite, zirkelite, and chevkinite were identified by electron probe analysis (with energy-dispersive attachment) and the chevkinite confirmed by X-ray diffraction. Brief comparison is made with other Tertiary occurrences of RE minerals. This is the first recorded occurrence of chevkinite in Great Britain.


Sign in / Sign up

Export Citation Format

Share Document