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Display spin specific parameter values.


value.display(param=None, scaling=1.0)

Keyword arguments

param: The parameter to display. Only one parameter may be selected.

scaling: The factor to scale parameters by.


The values corresponding to the given parameter will be displayed. The scaling argument can be used to scale the parameter values. This can be useful for example in the case of the model-free Rex parameter to obtain the spectrometer dependent value from the omega_ex field strength independent internal value. Or to scale correlation times from seconds down to nanosecond or picosecond timescales.

Relaxation curve fitting parameters

Please see Table 17.33 on page [*].

Table 17.33: Relaxation curve fitting parameters.
Name Description
rx Either the R1 or R2 relaxation rate
i0 The initial intensity
iinf The intensity at infinity

Steady-state NOE parameters

Please see Table 17.9 on page [*].

Model-free parameters

Please see Table 17.34 on page [*].

Table 17.34: Model-free parameters.
Name Description
s2 S2, the model-free generalised order parameter (S2 = S2f.S2s)
s2f S2f, the faster motion model-free generalised order parameter
s2s S2s, the slower motion model-free generalised order parameter
local_tm The spin specific global correlation time (seconds)
te Single motion effective internal correlation time (seconds)
tf Faster motion effective internal correlation time (seconds)
ts Slower motion effective internal correlation time (seconds)
rex Chemical exchange relaxation (sigma_ex = Rex / omega**2)
csa Chemical shift anisotropy (unitless)

For model-free theory it is assumed that Rex values are scaled quadratically with field strength. The values will be very small as they will be written out as a field strength independent value. Hence use the following formula to convert the value to that expected for a given magnetic field strength:

    Rex = value * (2.0 * pi * frequency) ** 2

The frequency is that of the proton in Hertz.

Reduced spectral density mapping parameters

Please see Table 17.11 on page [*].

Consistency testing parameters

Please see Table 17.12 on page [*].

Relaxation dispersion parameters

Please see Table 17.5 on page [*].

Prompt examples

To show all CSA values, type:

relax> value.display('csa')

To display the model-free Rex values scaled to 600 MHz, type one of:

relax> value.display('rex', scaling=(2.0*pi*600e6)**2)

relax> value.display(param='rex', scaling=(2.0*pi*600e6)**2)

The relax user manual (PDF), created 2020-08-26.