HBUIld { $<$hbuild-statement$>$ } END
is invoked from the main level of X-PLOR. The END statement activates hydrogen building.
selects atoms that should be perceived as acceptors for hydrogen bonds involving waters (default: all atoms that have an explicit ACCEptor assignment; see Section 3.1.1).
specifies the cutoff value for acceptors involving hydrogen bonds to waters (default: 7.5 Å).
specifies the step size in degrees for the dihedral angle search in cases where the placement of the hydrogens is not unique (default: 10$^{\circ}$).
is a flag that provides information about the partial energies during the local minimizations.
specifies a selection of atoms that should be built. Only hydrogens may be specified; hydrogens are defined in X-PLOR by their mass being less than 3.5 amu. An error statement will be returned if any of the selected atoms has a larger mass (default: (HYDRogen AND NOT KNOWn) ).

Xplor-NIH 2024-06-11