I know that refining the atoms positions is ´´too much´´, exagerated. But is
the only way I can make the calculated DRX pattern fit with the measured
one. There must a problem in the instrument details since I´m using
Fundamental Parameters (FP) for peak shape, the values I put in the
instrument description play a major role in FP, am I right?
I made a new scan, of the same sample, with range from 10° to 80°, step size
0,02 and count time 4 seconds. The old one was from 5° to 120,° maybe it is
prejudicing the background refining.
Tomorrow I´m gonna to scrap this old pattern and work with the new one. I´m
having a good response refining the calcite and teh dolomite in the sample
only refining lattice parameters, cry size and beq. I think that refining
this is what we can call a ´´normal refining method``. Now the kaolinite...
The major problem is that I have a sample from a laterite with
hydroxyapatite, calcite, dolomite, vermiculite and other phases. The
vermiculite is very alterated and in the DRX pattern we can confuse it with
other ``layered silicates``, it will be a huge problem. But I will only put
my hands on these samples after finishing with the kaolinite. One question,
these ´´models`` and ´´trials`` that you talk about regarding the kaolinite
is used in the CIF part of the refinement, am I right?! It´s not a part of
the TOPAS itself. right?
Thank you,
Leandro
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