GC008 Chromatographic terms and symbols - Part 1

 Symbols recommended by the IUPAC are indicated with (IUPAC) after their definition. The terms without this clarification are other symbols and names in use.

Kc: distribution constant (for GLC) (IUPAC)

Kp: partition coefficient

KD: distribution coefficient

k: retention factor (IUPAC)

k′: capacity factor; capacity ratio; partition ratio

N: plate number (IUPAC)

n: theoretical plate number; no. of theoretical plates

H: plate height (IUPAC)

HETP: height equivalent to one theoretical plate

R: retardation factor (in columns) (IUPAC)

RR: retention ratio

Rs: peak resolution R (IUPAC)

alpha: separation factor (IUPAC) - Selectivity; solvent efficiency

tR: retention time (IUPAC)

VR: retention volume (IUPAC)

VM: holdup volume (IUPAC)

Volume of the mobile phase;

VG: volume of the gas phase

VO void volume; dead volume

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