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There are several functions in EasySpin that simulate continuous-wave EPR spectra: chili (slow-motion), garlic (isotropic limit), pepper (solid-state limit).

All of these functions take a common set of experimental parameters that define the spectrometer settings. When calling any of these functions, these settings are given in the second parameters. For example, they should be given in the structure `Exp`

in the following call

pepper(Nitroxide,Exp,Opt);

The following table lists all possible fields in the experiment structure `Exp`

.
Of these fields, only very few are mandatory: You need to specify `mwFreq`

for a field sweep, or `Field`

for a frequency sweep.

`mwFreq`

(For field sweeps only). Spectrometer frequency, in GHz. E.g.

`Exp.mwFreq = 9.5;`

for X band.
For frequency sweeps, omit this field and use `Exp.Field`

.
`CenterSweep`

(For field sweeps only). *2-element vector*

Contains center and sweep width of the sweep range. For magnetic field sweeps, values should be in mT, e.g.

`[center sweep]`

Contains center and sweep width of the sweep range. For magnetic field sweeps, values should be in mT, e.g.

`Exp.CenterSweep=[310 100]`

.
For frequency sweeps, values should be in GHz, e.g. `Exp.CenterSweep=[9.5 1]`

.
The sweep range can be specified either in `CenterSweep`

or in `Range`

. If both are given, `CenterSweep`

has precedence.

`Range`

(For field sweeps only). *2-element vector*

Contains lower and upper limit of the field sweep range. Values should be in mT, e.g.

`[lo hi]`

Contains lower and upper limit of the field sweep range. Values should be in mT, e.g.

`Exp.Range=[260 360]`

.
The sweep range can be specified either in `CenterSweep`

or in `Range`

. If both are given, `CenterSweep`

has precedence.

`Field`

(For frequency sweeps only). Static magnetic field, in mT. E.g.

`Exp.Field = 1000;`

for a 1 T field.
For field sweeps, omit this field and use `Exp.mwFreq`

.
`mwCenterSweep`

(For frequency sweeps only). *2-element vector*

Contains center and sweep width of the frequency sweep range. The values should be in GHz, e.g.

`[center sweep]`

Contains center and sweep width of the frequency sweep range. The values should be in GHz, e.g.

`Exp.mwCenterSweep=[9 10]`

.
The sweep range can be specified either in `mwCenterSweep`

or in `mwRange`

. If both are given, `mwCenterSweep`

has precedence.

`mwRange`

(For frequency sweeps only). *2-element vector*

Contains lower and upper limit of the frequency sweep range. Values should be in GHz, e.g.

`[lo hi]`

Contains lower and upper limit of the frequency sweep range. Values should be in GHz, e.g.

`Exp.Range=[9 10]`

.
The sweep range can be specified either in `mwCenterSweep`

or in `mwRange`

. If both are given, `mwCenterSweep`

has precedence.

`nPoints`

Number of points along the horizontal axis (magnetic field for field sweeps, microwave frequency for frequency sweeps). If not given, the default is 1024.

`Harmonic`

`0`

, `1`

(default) or `2`

Harmonic of the detection.

`1`

and `2`

specify the first and the second harmonic of the absorption spectrum, detected using field modulation. `0`

returns the absorption/dispersion spectrum directly. To explicitly include the effect of field modulation, use `Exp.ModAmp`

.
`ModAmp`

Modulation amplitude (peak-to-peak), in mT. If not given or set to zero, harmonics are calculated using simple differentiation. This setting is only used for field sweeps. It is not available for frequency sweeps.

`mwPhase`

The reference microwave phase, in radians. 0 is pure absorption (default value), and

`pi/2`

is pure dispersion. `mwPhase`

allows you to include absorption/dispersion admixture in the simulation.
`Temperature`

Gives the temperature of the spin system in the EPR experiment, in kelvin. If given, Boltzmann
populations are computed and included in the EPR line intensities. E.g.,

`Temperature = 298`

corresponds to room temperature. If not given (or set to `inf`

), all transitions are
assumed to have equal polarizations.