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Next: Requirements Up: NCS Restraints Previous: NCS Restraints


Syntax

NCS RESTraints { $<$NCS-restraints-statement$>$ } END
is invoked from the main level of X-PLOR.
$<$NCS-restraints-statement$>$:==
GROUp
{ $<$ncs-restraints-group-statement$>$ } END adds a new group to the restraint NCS database.
INITialize
erases the current restraint NCS database. If no restraints are specified, the energy flag NCS should be turned off as well.
$<$NCS-restraints-group-statement$>$:==
EQUIvalence=$<$selection$>$
adds a new set of NCS-equivalent atoms within the group to the restraint NCS database.
SIGB=$<$real$>$
gives the target deviation ${\sigma}_{ncs}$ for B-factor restraints (deviation from the average B of equivalent atoms) in Å$^2$ (default=2.0 Å$^{2}$).
WEIGht=$<$real$>$
gives the effective energy constant for the positional restraints in kcal mole$^{-1}$ Å$^{-2}$ (default: 300.0 kcal mole$^{-1}$ Å$^{-2}$).

Xplor-NIH 2024-09-13