Diffraction calculator of hexagonal unit cells.

Enter the number of shells in the 2D-hexagonal unit cell, the hexagonal lattice spacing d, their radii r, their electron densities c and their shapes (circular or hexagonal). Radii should be increasing from 1 to 10 and overlapping of hexagons and circles should be avoided. The first 20 diffraction peaks of the hexagonal lattice will be calculated (note: the 20th peak is shared by two reflections: 5/3 and 7/0). The values are listed h^2+k^2+hk, q(hk), and y-data. These (y) can be either the amplitudes F(q) or the intensities I(q). Optionally the intensities I(q) can be multiplied by the multiplicities of the respective peaks (*M) and further also be divided by hk^2 (Lorentzfactor, /x**2). Units are arbitrary (A or nm) and can be copied and pasted from the window into any text-file for further processing and graphical displaying. The electron density will then be recalculated from the selected number of diffraction peaks (Nr peaks, max. 20) and plotted for Nr points from the center of the unit cell up to rmax (for one unitcell rmax = d/2). F(0) will also be calculated, but not used in the electron density calculations.

Calculation Input h*h+k*k+hk, q, y-data(q) Plot Input
shells d
r(1) c(1)
r(2) c(2)
r(3) c(3)
r(4) c(4)
r(5) c(5)
r(6) c(6)
r(7) c(7)
r(8) c(8)
r(9) c(9)
r(10) c(10)

Nr (points)
Nr (peaks)

Author: M.Kriechbaum, TU-Graz (2018), e-mail: manfred.kriechbaum@tugraz.at