PAMoC User's Manual

or | origin | momentor

Synopsis

[-](or|origin|momentor)   N

Description

This option defines the origin of the molecular electrostatic moments. The available option values are:

NMeaning
0center of mass (the default)
1the origin of the IDF axis system, i.e. (0, 0, 0)
Remarks

Monopoles, m(0), do not change under translation of the axis system, because they are scalars. The components of the dipole remain unchanged under translation of the axis system only if the monopole is null. In general, a symmetric Cartesian tensor m(n) of order n is invariant under translation of the axis system provided that all the symmetric Cartesian tensors of lower order, up to n−1, are null. On the other hand, the translation of a polytensor, whose component tensors are all null but the monopole m(0), generates a polytensor with non-null component tensors of any order.[1]

Related Keywords
References
  1. "Cartesian Multipole Moment Tensors and Polytensors."
    In "PAMoC User's Manual".