I have found these statistics from the Cambridge Structural Database from January 2014 (see below). As you can see, most of the uploaded structures have an R factor between 0.03 and 0.07. If an R factor is "good", strongly depends on the crystal/compound. In some cases (e.g. disorder) a factor of 0.05 can be absolutely alright and in other cases, if the circumstances can be explained, even a structure with an factor of 0.10 can be published (2.2 % of the database). Nevertheless, you should always try to solve and refine the structure to the lowest R factor possible.
R-factor range ; No. in range ; % CSD ; Cumulative %
0.0100 - 0.0300 ; 75293 ; 11.0 % ; 11.0 %
0.0301 - 0.0400 ; 142567 ; 20.8 % ; 31.8 %
0.0401 - 0.0500 ; 155880 ; 22.7 % ; 54.5 %
0.0501 - 0.0700 ; 186432 ; 27.1 % ; 81.6 %
0.0701 - 0.0900 ; 69394 ; 10.1 % ; 91.7 %
0.0901 - 0.1000 ; 15418 ; 2.2 % ; 93.9 %
0.1001 - 0.1500 ; 20955 ; 3.1 % ; 97.0 %
0.1501 - ; 4345 ; 0.6 % ; 97.6 %
Dear Toblas,
Is there any reference one can refer to? if yes kindly give me some suggestions.
Thank you.
Mr. Raghavan,
Generally R below 10 % for organics and below 3 % for inorganics. In spite of that we have examples of 1 % for organics (ref. 1).
[ref.1] Salts of aromatic amines: Crystal structures, spectroscopic and non-linear optical properties, Bojidarka Ivanova, Michael Spiteller,
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 77, 2010, 849–855
Dear Prof.Ivanova,
Thank you for your kind reference. I have got some usefull points from your reference.
Thank you.
That is correct , up to 2 is acceptable if you have a value of 4, your crystal is not going to be published.
If R-factors values are < 5% for any refinement of structural model , it is good.
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