Hi,
You take the output mtz from the refinement program (let's assume it's
called refine_1.mtz).
Command line mode:
sftools
read refine_1.mtz col 1 2 3 4 # assuming the mtz contains H K L 2FOFCWT
PHI2FOFCWT FOFCWT PHI2FOFCWT
cal col 3FO2FCWT col 1 col 3 +
set types
F
P
F
P
R F
write 3fo2fc.mtz col 5 2 3 4
quit (or stop, can't remember which)
That's it...
Fred
Armando Albert de la Cruz wrote:
Does anyone have got a script to compute 3fo2fc map with CCP4?
Armando
El 29/07/2010, a las 23:38, Ian Tickle escribió:
On Thu, Jul 29, 2010 at 8:25 PM, Pavel Afonine <pafon...@lbl.gov> wrote:
Speaking of 3fo2fc or 5fo3fc, ... etc maps (see classic works on this
published 30+ years ago), I guess the main rationale for using them
in those
cases arises from the facts that
2Fo-Fc = Fo + (Fo-Fc),
3Fo-2Fc = Fo +2(Fo-Fc)
To be precise, it is actually
2mFo-DFc for acentric reflections
and mFo for centric reflections
I prefer to think of it rather as
2mFo - DFc = DFc + 2(mFo-DFc) for acentrics and
mFo = DFc + (mFo-DFc) for centrics.
Then it also becomes clear that to be consistent the corresponding
difference map coefficients should be 2(mFo-DFc) for acentrics and
(mFo-DFc) for centrics.
Cheers
-- Ian
