Hi,
i just have a small question about the use of
<R-3> noe distance averaging option.

i understand that this option calculates
the distance between a proton and another *one* that
is jumping through several sites a lot faster then overall tumbling. (i
emphasised *one* because that follows from the description of analogous
<R-6>
option in the manual
http://atb.slac.stanford.edu/xplor/manual/node358.html#noeaveraging
)

now if i have a methyl group that is rotating through its three minimum
energy sites i have three such protons. should i therefore use scaled
distance restraint

d_scaled = d_raw * N^(-1/6), with N=3 for the three methyl protons.
where d_raw = (cal_const/cross_peak_intensity)^(-1/6)
(or in other words use scaled noe signal to get a contribution from an
individual 'jumping' atom)

or XPLOR does that scaling automatically and i could just use the 'raw'
distance restraint?

Thank you.
Evgeny.

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