If an external static field is included in the
simulation then one or more of these can be added under the Simulation object as required, and
describe the relative orientation of the static fields with
respect to the absorbed or emitted radiation. If none are present
random polarization is assumed. If no external field is present
the object is ignored. See Transition
Moments and Line Strengths for a note on how Spol
values should be interpreted in the presence of a field.
||Select the polarization of the light, and thus the M selection rules.
Possible values are:
(Rank = 1 for a normal single photon transition)
- Random -
- ΔM = 0
- ΔM =
rank, rank−2, ... −rank
- ΔM =
Note that PGOPHER versions before 8.0.186 also
had a rank setting, and also relative intensities for random
polarisation or rank ≠ 1 were not calculated correctly.
Versions before 10.0.21 only included ΔM = ±rank transitions
transitions, which is correct for rank 1 but not for higher ranks.
As part of the implementing this correctly a scale factor for
parallel transitions for rank > 1 was also introduced
(1/sqrt(6) for rank 2) which will affect absolute intensities.
||Relative strength of this component of the field - note
that the relative intensity is proportional to the square of