Sorry I forget to tell ya the details:
The SG of my Data is cubic P4332. Cell is 251.34A in all three dimensions.
Resolution is 3.1A. 5,6,7,8 might be the possible copies from Matthew
coeficient. But I just trust 6 because Chinese like the number 6
(happy Chinese new year by the way :)). No pseudo translation judged by
Native Patterson. Self-rotation at the section kappa=180 shows strong
peaks at phi=45 and psi=45.At the stage of map generation, the Rfree is
42% R is 38%.
Thanks!
Yanming
On Tue, 13 Feb 2007, Eleanor Dodson wrote:
> Sometimes this sort of disorder is due to an error , so the first thing is to
> check very carefully that the solution makes sense.
>
> Why are you so sure there are 6 copies in the asymmetric unit?
>
> In situations like this I first worry about SG.
>
> Is there a pseudo-translation vector? This can make it hard to decide on the
> SG..
>
> Is there an alternate spacegroup with fewer molecules in the asymm unit?
>
> What does the self rotation show?
>
>
>
> Yanming Zhang wrote:
>> Dear All,
>>
>> Maybe this is a trivial question:
>>
>> My data should have 6 molecules in one assymetric unit. MR could find out
>> 4 molecules. After this, no matter how hard I have tried, no more molecules
>> can be found. At this stage, I suppose that all other copies are
>> dis-ordered. And go ahead to do refinement with 4 molecules (ABCD)
>> available.
>> The density for A is quite good. But for BCD are very dis-ordered. Many
>> breaks in chains. I'd like to ask you:
>> In a situation like this, should I:
>> A, Use NCS for all copies?
>> B Do not use NCS at all?
>> C, Use NCS just for BCD? (even dis-ordered, but similar)?
>> What is the trick to lower down Rfree as soon as possible, if you have
>> experienced the same situation before?
>>
>>
>> Thanks
>>
>> Yanming
>>
>>
>
>
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