[ Identification | Description | Input parameters | Output parameters | Links ]

The Perfect_crystal Component

Perfect crystal with diamond or zincblende structure

Identification

Description

Reads atomic formfactors from a data input file.
The PerfectCrystal code reflects ray in an ideal geometry, does not include surface imperfections or mosaicity

The crystal is positioned such that the long axis of the crystal surface coincides with
z-axis. The angle between the Bragg planes and the crystal surface is alpha

The algorithm:
 Incoming photon's coordinates and direction (k-vector) are transformed into an elliptical reference frame 
(elliptical parameters are calculated according to the mirror's position and its focusing distances and the  * incident angle), the intersection point is then defined. 
A new, reflected photon is then starting at the point of intersection.
Notation follows Tadashi Matsushita and Hiro-O Hashizume, X-RAY MONOCHROMATORS. Handbook on Synchrotron Radiation,North-Holland Publishing Company, 1:263–274, 1983.

Input parameters

Parameters in boldface are required; the others are optional.
Name Unit Description Default
form_factors "FormFactors.txt"
material "Si.txt"
length along z-axia [m] length of the crystal 0.05
width along x-axis [m] width of the crystal 0.02
V Å^3 unit cell volume 160.1826
h 400 ,k,l indices of reflection (111)(220) 1
k 1
l 1
alpha alpha=0 for symmetric reflection, ie the Bragg planes are parallel to the crystal surface [rad] asymmetry angle 0.0

Output parameters

Name Unit Description Default
prms_m  
a  
b  
c  
M  
Z0  
Y0  
xi  
cost0  

Links

[ Identification | Description | Input parameters | Output parameters | Links ]

Generated automatically by McDoc, Peter Willendrup <peter.willendrup@risoe.dk> / Fri Sep 2 21:40:01 2011