Simulating emission spectra requires some
particular settings, given below. If these are set, PGOPHER will use a
Boltzmann distribution to calculate the population in the upper
state, and assume no population in the lower state
- The Initial flag
must be set for the upper
manifold of each transition.
- The Fluorescence
flag should be set to true for the simulation.
- The AbsoluteE
setting in the molecule(s) should be set to true.
- The band origins should be must be absolute so, for example,
do not enter 135 cm-1 rather than 19135 cm-1
for an origin.
- To include the ν3 factor in the intensity
calculations the IntensityUnits
in the Simulation object should be set to HzperMolecule,
giving integrated line strengths are then photons/s/molecule.
Alternatively WperMolecule will scale these by hν
giving units of W/molecule.
For versions before 10.1.146 the Fluorescence
not present and a different logic was used, which will be used in
the current version if either is false:
- If the Fluorescence
setting is false the Initial
must be false for the lower manifold for each
transition, in addition to being set true (as above) for the
upper manifold. For simple cases (widely separated manifolds)
this is equivalent to the Fluorescence
true setting, but will not simulate fluorescence within a
manifold, and will omit some transitions for overlapping
- If AbsoluteE
is false then a heuristic is used to detect when relative or
offset band origins have been used, such as entering 135
rather than 19135 for an origin. This flag permits negative
transition frequencies, but the heuristic is not infallible,
and can give inappropriate negative transition frequencies.