|Objects Mixture||<Prev Next>|
|IntensityUnits||Units for intensity. These are described in detail under Intensity Formulae.
Possible values are:
Misleading results can be obtained for a setting of Arbitrary when simulating isotopologues or isotopomers with different symmetry or statistical weights together, such as 35Cl2 and 35Cl37Cl. The calculation is "correct", in that the partition function is necessary to give the correct relative intensities, but is excluded by design for this setting.
|LifeModel||Model to use for state dependent lifetimes and linewidths.
Valid values are lmNone, lmWidth, lmProduct, lmProductWidth,
lmParent, lmParentWidth, lmGate, lmGateWidth. See Widths and Lifetime Effects for how
this setting works.
|PlotUnits||Units for the horizontal scale for spectrum plots.
Possibilities are standard energy units (cm1, MHz,
Kelvin and eV) as in the Mixture object and also:
|Fluorescence||Set to always discard lower state population; see Emission Spectra for further discussion of this flag.|
|nDF||Number of points (between Fmin and Fmax) to calculate the spectrum at. Note that if a peak width is less than 3*(Fmax-Fmin)/nDF, i.e. only a few points wide, then it is shown as a stick, rather than a peak.|
|WidthMult||Multiple of line width to extend convolution over.|
|AutoMin||If set (the default), Ymin is automatically updated to minimum point in plot range|
|AutoMax||If set (the default), Ymax is automatically updated to maximum point in plot range|
|ShowSum||Plot overall sum of individual spectra. This is toggled by the button.|
|ShowParts||Plot individual spectra making up overall spectrum. The individual spectra are grouped by colour, so you will need to set colours to see something different to the sum. Colours can be set at the transition moment, state, molecule or species level. This is toggled by the button.|
|ShowFortrat||Plot a Fortrat diagram, i.e. J against frequency, in the main window. This is toggled by the button.|
|UseUpper||Set to use upper rather than lower state J and symmetry in the Fortrat diagram.|
|ShowSymmetry||Show symmetry in Fortrat plots.|
|ShowDeltaJ||Show change in J in Fortrat plots.|
|ScaleMarkSize||Scale Mark Size with intensity in Fortrat plots.|
|UseSymmetry||If true, show different symmetries in separate Fortrat plots.|
|UseStateNumber||If true, show different state numbers in separate Fortrat plots.|
|FortratQno||Select quantum number to use in Fortrat plots.|
|PreserveArea||If set, then changing the PlotUnits
changes the vertical scale, giving a constant area to peaks.
This implies the units of the vertical scale depend on the
horizontal scale. For example, if units of cm2WavenumberperMolecule
are selected for IntensityUnits and the PlotUnits
are MHz the vertical scale units are actually cm2wavenumber/molecule/MHz
to give integrated peak areas (calculated from the numerical
values plotted) of cm2wavenumber/molecule
independent of the PlotUnits. Versions of PGOPHER
before 10.1 did this by default.
The default in newer versions is to not set this parameter, and thus always plot the same quantity for intensity. Changing the PlotUnits thus does not change the vertical scale, which is less confusing when comparing to experimental spectra or doing contour fits.
|SeparateScales||When showing multiple plots, scale plots
separately, rather than requiring the same scale factor for
|LogScale||Take ln of vertical axis on plots. (Initial
|Fmin||Left edge of plot range in main window.|
|Fmax||Right edge of plot range in main window.|
||Lower end of current plot
range; overwritten with lowest value in current range if AutoMin set
|Ymax||Upper end of current plot range; overwritten with lowest value in current range if AutoMin set|
|Temperature||Rotational temperature (Kelvin). Setting this < 0 will force the use of numerical populations for all manifolds, as described in Non-Boltzmann Populations.|
|Gaussian||Gaussian contribution to linewidth (full width half
maximum). If both this and a Lorentzian width (below) is set
the result is a convolution of the two, a Voigt profile.
Note that this is in PlotUnits, and is taken to be
constant over the plot range, which may be a concern if the
plot range is large, as a width that is constant in
wavelength will not be constant in frequency.
|Lorentzian||Lorentzian contribution to linewidth (full width half maximum). This and the Gaussian width can also be set from the main window. Note that this is in PlotUnits, and is taken to be constant over the plot range, which may be a concern if the plot range is large, as a width that is constant in wavelength will not be constant in frequency.|
|Foffset||Frequency offset to simulation.|
|SMargin||This setting controls the number of extra points to
calculate at each end of the spectrum. (These points are not
plotted, but may be required to avoid artefacts in the
If > 0: Number of extra points to calculate at each end
If < 0: Number of points is |SMargin|*WidthMult*(Gaussian+Lorentzian)
|OThreshold||Ignore peaks smaller than this fraction of the maximum
peak intensity in selected simulations. In line listings,
lines with an intensity less than this are excluded from the
printout; in this case the value is absolute, rather than a
fraction of the strongest. Note that line lists produced by
File, Export, Line List use a separate value that is a
fraction of the maximum intensity.
|RefWidth||Reference width in linewidth (predissociation)
calculations; see LifeModel
|Tvib||Vibrational Temperature (Kelvin); set to -1 (default) to use rotational temperature for all Boltzmann factors.|
|MinI||Discard lines weaker then this fraction of the strongest
in Fortrat plots. Note that the default for this increased
from 0 to 0.01 in 10.0.31.
|Saturation||Zero for normal calculation; positive values progressively
switch strength to population only by replacing the line
strength, S by:
S = (1-exp(-S*Saturation/g))*gwhere g = Min(2J'+1, 2J"+1)*Statistical Weight. This is appropriate for saturation by z polarized light. Values of, say, 1 to 10 will wash out the differences between allowed branches and much higher values will bring out transitions that are only allowed by some weak mixing.
Spin temperature (Kelvin); set to -1 (default) to assume
equilibrated nuclear spin states. If set >=0 then the
fraction of molecules with each particular nuclear spin
species (ortho/para for diatomics) is fixed at the
fractions found at T = Tspin. This is often appropriate
for molecular beams, where the nuclear spin states do not
relax during the expansion. There are two limitations in
the current implementation, which may lead to incorrect
|IScale||Scale all simulated intensities by this
value. (The default is 1.)
|EField||Static electric field, V/m;
see External Fields - The Zeeman
and Stark Effects
|BField||Static magnetic field in Tesla (= 104 Gauss); see External Fields - The Zeeman and Stark Effects|
||Plot each transition as two peaks, split by 2*Doppler*Centre Frequency. This gives the double peak structure often seen in Fourier transform microwave spectroscopy.|
||Fraction of plot area to use for the
simulation where simulation and overlay plots are separated.
The possible range is -1..1, with 0.5 the default. Negative
values put the simulation, rather than the overlay, at the
Right click on the item in the constants
window for the following operations in addition to the
||Print a table in the log window of the intensity at the central frequency/wavelength of the simulation. You are prompted for the temperature step size, and the values tabulated will be from 0 to the temperature of the simulation.|