Taking unit cell parameter esds from data processing into Topas single crystal structure refinement

lksbath

Hello,

Is it possible to use/implement the unit cell parameter esds output from single crystal XRD data processing (by xia2 etc) when doing a single crystal refinement in Topas?

Thanks,
Lucy

mfisch

This?

consider_lattice_parameter

rowlesmr

Or if you're bringing parameters from other programs into Topas (v6), then you could use prm_with_error

alancoelho

consider_lattice_parameter wont work as the lattice parameters would have zero derivatives.

I think what might work is:

str
prm_with_error !ea 10_0.034
prm_with_error !eb 11_0.022
a = ea;
b = eb;
...

where 10 is the a lattice parameter and associated error of 0.034 etc...

I am yet to test the above but give it a try.

lksbath

thanks all for your suggestions. I will give Alan's suggestion a try and let you know how I get on.
Lucy

lksbath

Your suggestion works Alan thank you, though I'm not sure whether it has had any effect of the structure refinement.