Alison, Given:
> There is a pseudo-translation with 55 % peak at a fractional
> coordinate of 0.5, 0.5, 0.48.
I don't think you can be certain about:
> Systematic absences along a and b axis were observed thus the
> dataset was scaled in P21212 space group.
Try testing all eight possible Ortho. sp. grps, and also be prepared to
consider P2 or P21.
The pseudo-centring you see in the self-Patterson would seem to be
consistent w/ I222 (or very unlikely, I212121), or perhaps (C222 or
C2221) with NCS?
From Berhnard's Matthews Coeff. calc.
(http://www.ruppweb.org/Mattprob/):
+-----------------------------------------------------------------------
------+
| N(mol) Prob(N) Prob(N) Vm Vs Mw
|
| for resolution overall A**3/Da % solvent Da
|
+-----------------------------------------------------------------------
------+
| 1 0.0021 0.0027 10.77 88.58 9900.00
|
| 2 0.0033 0.0053 5.38 77.15 19800.00
|
| 3 0.0662 0.0920 3.59 65.73 29700.00
|
| 4 0.4170 0.4550 2.69 54.31 39600.00
|
| 5 0.4861 0.4267 2.15 42.88 49500.00
|
| 6 0.0233 0.0156 1.79 31.46 59400.00
|
| 7 0.0021 0.0027 1.54 20.04 69300.00
|
+-----------------------------------------------------------------------
------+
It looks like you have a higher symmetry (centered) space group, or you
have NCS.
Is your heavy atom search "space group agnostic"?
Dave
David Borhani, Ph.D.
D. E. Shaw Research, LLC
120 West Forty-Fifth Street, 39th Floor
New York, NY 10036
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212-478-0698
http://www.deshawresearch.com
|