The Plane definition starts with clicking on the Lspl button followed by clicking on the atom centres of the atoms participating. The sequence is ended (and the calculation initiated) by clicking in the End field.
Plane determining atoms may be separated from those for which the distance to the plane only has to be calculated by clicking on the Dist field between the clicks on atoms.
Alternatively, an instruction similar to LSPL c3 c4 c5 DIST c1 could be issued from the keyboard.
Atoms are treated with unit-weight by default. Alternatives are are weighting based on atomic weights and standard deviations (esd, su). The weighting scheme may be changed using the (UAE)WLSPL button.