Location:

Report Variable (Peak Results)

Dimension:

see below for each moment

Default:

Zero moment

Related Variables:

Theoretical Plates, Resolution

Description:

Statistical moments often describe the chromatographic separation much better than the values for the theoretical plates and resolution. This is because statistical moments are not based upon an ideal Gaussian distribution, but on the actual statistical distribution of data points.

Parameters:

Zero Moment

The zero moment is the peak area:

With:

µ0 : Zero moment

t : Time in minutes

f(t) :  Baseline-corrected signal over time

The unit of the zero moment is the unit of measured value multiplied by the time in minutes, e.g., mAU*min.

First Moment

The first moment is the averaged retention time:

The unit of the first moment is minutes (min).

Second Moment

The second moment is the retention time variance (the narrower the peak, the smaller the variance):

The unit of the second moment is minutes squared (min²).