[cctbxbb] getting resolution for any "h" "k" "l" and cctbx

[Ralf W. Grosse-Kunstleve]

Hi Hari,

> 1) I was wondering if someone can point me to routines available from
> cctbx modules that can give me the "resolution" for a given index "h"
> "k" "l".  in any space group

To get the resolution for a given hkl, you just need the unit cell:

from cctbx import uctbx
uc = uctbx.unit_cell((11,12,13,93,98,103))
hkl = (2,3,4)
print uc.d(miller_index=hkl)
print uc.stol(miller_index=hkl)
wavelength = 1.3
print uc.two_theta(miller_index=hkl, wavelength=wavelength)

Save as "resolution_hkl.py" and run with:

  cctbx.python resolution_hkl.py

The .d(), .stol(), .two_theta() methods are documented here:

  http://cctbx.sourceforge.net/current/c_plus_plus/classcctbx_1_1uctbx_1_1unit__cell.html

> 2) In addition , if someone can point me in the direction of a well
> illustrated depiction of the derivation of the reciprocal lattice
> for the triclinic case , that will be very much appreciated bonus .

I'm not sure which textbook to recommend. I liked the old Buerger
books a lot, but I don't remember how he introduces the reciprocal
lattice.

Ralf