Dear Mateusz,
As far as I know we are just putting in splitting measurements at this
time. Precise coupling constant mesurements require special techniques
that correct for partial cancellation of positive and negative peaks.
There has been a few in teh litterature, from memory. That would be a good
thing to have, and we may well add it some day, but we are not close to
putting it in at the moment.
Yours,
Rasmus
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Dr. Rasmus H. Fogh Email: [log in to unmask]
Dept. of Biochemistry, University of Cambridge,
80 Tennis Court Road, Cambridge CB2 1GA, UK. FAX (01223)766002
On Thu, 29 Oct 2009, Wayne Boucher wrote:
> The 3J HN-HA that is currently in Analysis is the intensity-based 3D
> measurement where you compare the HN-HA peak with HN-HN diagonal.
>
> The splitting functionality will be added in the next couple of months (at
> least that is the current plan). Now how clever any of this will be for
> overlapped peaks is a hard question.
>
> Note that in 2.1.1 Analysis there is an option of setting the x, y location
> to be displayed in Hz, and to measure the difference between two
> user-specified points on the screen. I imagine that would help you right
> now.
>
> Wayne
>
> On Thu, 29 Oct 2009, Mateusz Maciejewski wrote:
>
>> Hello,
>>
>> I am currently working on a structure of a peptide, and have only natural
>> abundance samples of it. The approach I assumed to measure the HN-HA 3J
>> couplings was from a DQF-COSY, however, I couldn't find a way in
>> analysis2.0
>> to make precise measurements that would account for partial overlap of
>> in-phase and anti-phase peaks. Is there any way to actually make such
>> measurements in analysis2.0?
>>
>> Regards,
>> Mateusz Maciejewski
>>
>
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