Orientation of the fields

When the atomic coordinates are input in z-matrix format, the direction of the homogeneous field and the location of the point charges as specified in input are interpreted as referring to the standard Cartesian frame associated with z-matrix input. The standard frame means: the first atom at the origin, the second on the positive x-axis, the third in the xy-plane with positive y.

If the program rotates (and translates, as the case might be) the atoms from the input frame - or the auto-generated frame in case of z-matrix input - to some other frame, for instance to accommodate the internal ADF symmetry orientation requirements, the fields are transformed along with the atoms.