[ Identification | Description | Input parameters | Output parameters | Links ]
Bragg_crystal_bent
Component* Bragg_crystal_bent.comp supercedes Perfect_Crystal_bent.comp with major edits and corrections. * * For details see: * The optics of focusing bent-crystal monochromators on X-ray powder diffractometers with application to lattice parameter determination and microstructure analysis, * Marcus H. Mendenhall,* David Black and James P. Cline, J. Appl. Cryst. (2019). 52, https://doi.org/10.1107/S1600576719010951 * * Reads atomic formfactors from a data input file. * * The crystal code reflects ray in an ideal geometry, does not include surface imperfections or mosaicity * The crystal planes from which the reflection is made lies in the X-Z plane on the unbent crystal rotated * by an angle alpha about the Y axis with respect to the crystal surface. * * The external geometry of the crystal follows that of Elliptic_mirror.comp. * I.e. the crystal is positioned such that the a-axis of the ellipsoid is on the * z-axis, the b-axis is along the y-axis and the c is along the x-axis. * The reference point of the crystal is the ellipsoid centre, offset by one half-axis along the y-axis. * (See the component manual for Elliptic_mirror for a drawing). * * Notation follows Tadashi Matsushita and Hiro-O Hashizume, X-RAY MONOCHROMATORS. Handbook on Synchrotron Radiation,North-Holland Publishing Company, 1:263–274, 1983. * * Non-copyright notice: * Contributed by the National Institute of Standards and Technology; not subject to copyright in the United States. * This is not an official contribution, in that the results are in no way certified by NIST. * * NOTE: elliptical coordinate code and documentation taken from Mirror_elliptic.comp distributed in McXtrace v1.2 * However, the coordinates are rotated to be consistent with Bragg_crystal_flat.comp and Perfect_Crystal.comp. * Idealized elliptic mirror with surface ellipse and lattice ellipses independent, to allow construction of * Johansson optics, for example. * *
Name | Unit | Description | Default |
x_a | 0 | ||
y_b | 1.0 | ||
z_c | 1.0 | ||
lattice_x_a | 0 | ||
lattice_y_b | 1.0 | ||
lattice_z_c | 1.0 | ||
length | 0.05 | ||
width | 0.02 | ||
V | 160.1826 | ||
form_factors | "FormFactors.txt" | ||
material | "Si.txt" | ||
alpha | 0.0 | ||
R0 | 0 | ||
debye_waller_B | 0.4632 | ||
crystal_type | 1 | ||
h | 1 | ||
k | 1 | ||
l | 1 | ||
structure_factor_scale_r | 0.0 | ||
structure_factor_scale_i | 0.0 |
Name | Unit | Description | Default |
prms | |||
a2inv | |||
b2inv | |||
c2inv | |||
l_a2inv | |||
l_b2inv | |||
l_c2inv |
Bragg_crystal_bent.comp
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[ Identification | Description | Input parameters | Output parameters | Links ]
Generated on 2021-08-13 08:57:53