UPDate computes the NOE intensities from the current atomic model. The distance to an unresolved group is calculated as , where the exponent av is set with the AVERage command. A diagonal leakage rate is added to the relaxation matrix for each unresolved group. The main use of this command is for methyl groups. A methylene group is recognized by X-PLOR as two hydrogens bound to a heavy atom.
METHyl treats each methyl group as an unresolved group of protons.
A methyl group is recognized by X-PLOR as three hydrogens bound to a heavy atom. NONE deletes all previously defined unresolved groups.