Although the K 0 values are nearly the same with those of previous studies for both the P2 1 /c and C2/c phases, the K' 0 values are slightly smaller. The parameters are V 0 = 405.0 (2.6) Aa 3, K 0 = 106.9 (25.9) GPa, K' 0 = 5.3 (3.9), a 0 = 2.01 (44)X10 (super -5) K (super -1), a 1 = 2.10 (1.1)X10 (super -8) K (super -2), and (delta K T /delta T ) P = -0.021 (10) GPa/K. Laue discovered XRD and afterward, an alternative measurement technique and simple explanation for monochromatic X-ray diffraction was proposed by Bragg 30. For the C2/c phase, we determined the high-temperature EOS, expressed as P = 3/2 K T, where K T = K 0 +(delta K T /delta T) P (T-300), K' T = K' 0, V T = V 0, where thermal expansivity alpha (T) is a 0 + a 1 T. The pressure-volume-temperature data for P2 1 /c and high pressure C2/c clinoenstatite were fit to room-temperature third-order Birch-Murnahan equations of state (EOS) using the parameters: volume of V 0 = 415.4 (5) Aa 3, isothermal bulk modulus of K 0 = 108.5 (6.4) GPa, and its pressure derivative of K' 0 = 4.5 (1.3) for the P2 1 /c phase, and V 0 = 405.1 (1.7) Aa 3, K 0 = 106.4 (17.4) GPa, and K' 0 = 5.4 (2.7) for the C2/c phase. 1994) that these two clinoenstatite phases differ at high pressures and high temperatures. This confirms the suggestion (Hugh-Jones et al. The beta angle of this high-pressure C2/c phase ranges from 101.4 degrees to 101.7 degrees, shows almost no variation with pressure and temperature, and is about 8 degrees smaller than that of the high-temperature C2/c phase previously reported. Low clinoenstatite with space group P2 1 /c transforms to high-pressure C2/c clinoenstatite at high pressures and high temperatures, accompanied by a volume reduction of about 2.5%. Role of Ca2+ doping on the structure, magnetic, and magnetocaloric properties of La0.75Gd0.05Sr0.2−xCaxMnO3 (x = 0, 0.05, 0.075, and 0.Crystal structures and phase transitions of enstatite (MgSiO 3 ) were studied by in situ X-ray diffraction experiments using synchrotron radiation and a multi-anvil high-pressure apparatus at pressures to 12 GPa and temperatures to 1473 K. Wavelength of laser radiation : 632.8 nm. Distance between the spring and the screen : D 8.25 m. Magnetic moment impact on spin-dependent Seebeck coefficient of ferromagnetic thin films From the theory of diffraction, knowing the spacing, the minor and the major, we know how to calculate the linear dimensions of the obstacles that caused the diffraction. Using the above definition of D hkl, and in the absence of detailed shape information, K = 0.9 is a good approximation 5, 8. The structure of the formula is not affected by these definitions, but the numerical value of K may change appreciably 5, 7. In addition to depending on the crystallite shape, the numerical factor K also depends on the definitions of the average crystallite size (for example, if the cube root of the crystallite volume is used instead of the definition above) and the width (for example, if the integral line width is used, as in von Laue's derivation of Scherrer's formula 5, 6, rather than the full-width at half-maximum, which is usually easier to obtain from experimental data). The equation is D hkl = Kλ/( B hklcos θ), where D hkl is the crystallite size in the direction perpendicular to the lattice planes, hkl are the Miller indices of the planes being analysed, K is a numerical factor frequently referred to as the crystallite-shape factor 5, λ is the wavelength of the X-rays, B hkl is the width (full-width at half-maximum) of the X-ray diffraction peak in radians and θ is the Bragg angle. Scherrer derived his equation for the ideal condition of a perfectly parallel, infinitely narrow and monochromatic X-ray beam incident on a monodisperse powder of cube-shaped crystallites 1.
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