Hence we will observe more emission in the perpendicular direction than in the parallel direction and the resulting polarization will be negative.  Considering the same cos2 q photoselection rule and the sin q population distribution as before we can show that, if the absorption and emission dipoles are at 90o to each other, then P = -1/3.
These polarization values, in the absence of rotation, are termed limiting or intrinsic polarizations and are denoted as Po..    In general:
Where f is the angle between absorption and emission dipoles.
We can then understand that the limiting polarization of a fluorophore will depend upon the excitation wavelength. 
Polarization II