Various manufacturers and suppliers of GC columns provide lists of stationary phase properties and characterization parameters. One reference we provide here is to a document from Supelco that contains McReynolds constants for many stationary phases, as well as information on how such values are obtained and can be used.
As explained in Module 2.8 it is easy to characterize a stationary phase in terms of five McReynolds’ constants. All it requires is to measure isothermal retention indices (at 120oC) of five probes (i.e. benzene, 1-butanol, 2-pentanone, 1-nitropropane, and pyridine).
Apolar columns show low McReynolds’ constants, whereas polar columns exhibit high values. The average of the five McReynolds’ constants is a common indication for column polarity. Columns with similar McReynolds’ constants are expected to exhibit similar retention and selectivity.
In contrast it is difficult to characterize analytes Establishing their McReynolds’ constants would require measuring retention indices on six different columns, including one with squalane as stationary phase – a rare type of column nowadays.
For more on GC stationary phases see Section 2.1.4
For more on column characterization see Module 2.8
