Hi Troels, The relax GUI paper (http://dx.doi.org/10.1007/s10858-011-9509-1), the 2007 review of the Lipari and Szabo model-free problem (http://dx.doi.org/10.1039/b702202f) and 2008 model-free optimisation paper (http://dx.doi.org/10.1007/s10858-007-9214-2) that you mention are specifically for the Lipari and Szabo model-free analysis of standard R1, R2, and steady-state NOE relaxation. This does not apply in the same way when studying dispersion processes for the R2 relaxation.
I think there are some papers from the Palmer and Kay labs which talk about multiple field strength data requirements for relaxation dispersion studies using R1rho or CPMG-type pulse sequences. Generally it is better for stability in finding the solution to the dispersion equations when you have multiple field strength data, and the bigger the field strength difference or more fields the better. This is especially important for CPMG-type experiments or non-fast exchange processes. For R1rho with a process on the fast timescale, from what I've read I think it is acceptable to use single field strength data. But please do not trust my answers as I am not an expert in this area yet, you should look at the dispersion papers which discuss this issue. Unfortunately I do not remember the exact references off the top of my head and do not have them at hand, so you would need to perform a literature search. Regards, Edward On 16 May 2013 15:09, Troels Emtekær Linnet <[email protected]> wrote: > Hi relax. > > I read GUI 2011 paper and the 2007 review. > > It mentions the necessity to obtain experimental data at two different > field strength. > > We are equipped with a 750 and 800 MHz Varian spectrometer, and > I now wonder if this field separation is "enough". > > The 2008,a paper describes 500/600 MHz combination to solve the > double minimum problem. But I wonder if this could be solved also > for a 750/800 MHz data acquisition? > > Best > Troels Emtekær Linnet > > _______________________________________________ > relax (http://www.nmr-relax.com) > > This is the relax-users mailing list > [email protected] > > To unsubscribe from this list, get a password > reminder, or change your subscription options, > visit the list information page at > https://mail.gna.org/listinfo/relax-users _______________________________________________ relax (http://www.nmr-relax.com) This is the relax-users mailing list [email protected] To unsubscribe from this list, get a password reminder, or change your subscription options, visit the list information page at https://mail.gna.org/listinfo/relax-users
