**Electron density calculator for the 3D-cubic lattics Pm-3m (221), Fm-3m (225) and Im-3m (229)**
This Javascript calculates the 3D electron density distribution rho(r) of a cubic lattices of space group 221, 225 and 229 from diffraction data.
Enter the number of peaks (note: the hkl-reflections are listed for 221/225/229 and some are doublets!) and the value of the 3D-lattice spacing (d or length of the unit cell).
Enter the peak intensities I(q) or peak amplitudes F(q) and their signs of the scattering amplitudes (+ or -). Select the space group and the corrections already applied to the input data: 'none' means no corrections, LC means Lorentz correction (multiplied by q*q) and MC means multiplicity correction (divided by the multiplicities) have already been applied. F(q) have to be entered both LC and MC corrected. Optionally also I(0) or F(0) as a constant offset can be entered. Enter the value for rz (rz=0 means the 1/0/0 = 0/1/0 = 0/0/1 hkl-plane and rz=d/2 means the slice pararallel to the 1/0/0 plane through the center of the unit cell). The electron density, multiplied by a constant (f) will be calculated.
If f=0 then the electron density is divided by the volume of the unit cell.
Note that for the cubic spacegroups 221/225/229 the rx-ry, rx-rz and ry-rz planes are symmetry equivalent. For the calculation/plotting of
5 equidistant slices between rz and rz+d/2 for space group 229 click

here.
For 2*Nr points rho(r) at rz from -rmax = -rx = -ry to rmax = +rx = +ry will be calculated with the origin of the unit cell located at rx=ry=0. The color-scaling for the e-density data can be adjusted by entering the zmin and zmax levels. In case zmax <= zmin an autoscaling is done. The first (upper) 3D-Plot however is always autoscaled. If the calculation takes too long
(on a slow computer) decrease Nr.
The values are listed/plotted in rho(r) vs rx, ry in arbitrary units and can be copied
and pasted from the window into any text-file for further processing
and graphical displaying.