The R_2,eff values are calculated for the two point sampling scheme that is commonly used for the CT- CPMG experiments described in Frans A. A. Mulder, Nikolai R. Skrynnikov, Bin Hon, Frederick W. Dahlquist, and Lewis E. Kay, J. Am. Chem. Soc., 2001, 123, 967–975. The R_2,eff errors are derived using error propagation analysis based on the spectral noise.

Define your experimental intensity data in this section. More then one file can be uploaded, each file representing data measured at different magnetic field.

The input-file should have the following format:

1st line	Value of the B0 field for the nuclei of interest in MHz (e.g. 60.12).
2nd line	Value of the constant relaxation time for the CPMG experiment in seconds (e.g. 0.04).
3rd line	CPMG frequencies in (s-1).
4th line	Noise level for spectra measured at different vCMPG and reference spectra. Reference spectra noise level must be listed as a first entry
5th line	Comment line. In the example file, we described the data format (e.g. #residue I_ref I_vCPMG ...)
> 5th line	The first column specifies the residue one letter code and number, followed by the intensity in the reference spectra and the intensities at the CPMG frequencies specified in the 3rd line. The missing values should be specified as NA (not available).

60.12
0.040000
vCPMG      ref   50.000  100.000  200.000  300.000  400.000  500.000  600.000  700.000   800.000   900.000  1000.000
noise 3404.280 3404.280 3404.280 3404.280 3404.280 3404.280 3404.280 3404.280 3404.280  3404.280  3404.280  3404.280
#residue  I_ref I_vCPMG ...
A1    1702140.0   401586.7  380964.4  399136.8  432244.0  470716.2  524817.6  577182.4  615260.1  635014.4  660592.5  683629.5
B2    2094770.0   554908.3  579980.0  648026.7  722500.4  812130.3  825192.9  870851.8  865054.4  882115.3  901780.6  900937.1
C3    2301070.0   645496.1  658526.7  713688.8  816601.9  890347.2  917056.8  956372.7  958961.1     NA        NA        NA
D4    1511670.0   434443.6  444887.2  488337.6  548940.6  581184.3  599482.4  631493.9  644166.4  652242.5  661777.9  642723.1
E5    1956020.0   582484.4  641036.4  676107.0  759173.3  805109.5  832684.3  832439.5  844349.7  838884.4  863118.8  869382.9