Optical reconstructions are intensity based.
Xtallographic FT are amplitude based.
The theoretical value for xray is about 0.9*dmin.
Reading:
Stenkamp, R.E. and L.H. Jensen. 1984 Resolution revisited. Acta Cryst., A40,
251-254.
and the SFCHECK paper for other considerations
Vaguine AA, Richelle J, & Wodak SJ (1999) SFCHECK: a unified set of
procedures for evaluating the quality of macromolecular structure-factor
data and their agreement with the atomic model. Acta Crystallogr. D55,
191-20.
BR
-----Original Message-----
From: CCP4 bulletin board [mailto:[log in to unmask]] On Behalf Of
William Scott
Sent: Thursday, May 15, 2008 10:56 AM
To: [log in to unmask]
Subject: Re: [ccp4bb] poll: cutoff for "high resolution"
Actually, if you want to feel really good, I learned (in the context of
optics) that you can resolve two points separated by a distance x with a
diffraction limit of x/0.7, so this means you can start to see carbon -
carbon atomicity at 2.2 Å.
On May 15, 2008, at 10:12 AM, Gloria Borgstahl wrote:
> To me, it seems legal to use the words "atomic resolution" once we are
> within the carbon-carbon bond length. So I'm agreeing with Dr.
> Scott.
> Otherwise I'll never get to use the words...
>
> **********************************************************************
> ********
> Gloria Borgstahl
> Eppley Institute for Cancer Research and Allied Diseases
> 987696 Nebraska Medical Center
> 10732A Lied Transplant Center
> Omaha, NE 68198-7696
>
> http://sbl.unmc.edu
> Office (402) 559-8578
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> Associate Professor
> Hobbies: Protein Crystallography, Cancer, Biochemistry, DNA
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> Interests: ThimbleTack, skateboarding, RAGBRAI, and rollerskating
> **********************************************************************
> ********
>
>
>
> William Scott <[log in to unmask]> Sent by: CCP4 bulletin
> board <[log in to unmask]>
> 05/15/2008 12:09 PM
> Please respond to
> William Scott <[log in to unmask]>
>
>
> To
> [log in to unmask]
> cc
>
> Subject
> Re: [ccp4bb] poll: cutoff for "high resolution"
>
>
>
>
>
>
> On May 15, 2008, at 10:01 AM, Ed Pozharski wrote:
>
>> 1.2A (not surprisingly since this is about the length of covalent
>> bond).
>
> A carbon-carbon single bond is about 1.55 Å.
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