# The Thermodynamics of Chromatography - Other Thermodynamic Methods that are Used for Studying Chromatographic Systems > Optimum Operating Conditions for Chiral Separations in Liquid Chromatography > Page 62

It is clear,
that the optimum conditions for any given LC analysis (those conditions that
will produce a separation in the minimum time) can be very complex. In
addition, this complexity will be greater the more difficult the separation. In
the first instance, there will be an optimum temperature and optimum solvent
composition that will provide the optimum capacity ratios and separation ratios
for a given chiral pair. Added to that, the analysis time will depend on the
column length which, in turn, will be determined by the minimum efficiency
requirement. Furthermore, as the necessary efficiency is a complex function of *both* the *separation
ratio* of the chiral pair and their*capacity ratios*,the optimum solvent composition and temperature
will not necessarily be those that provide the maximum separation ratio and/or
the minimum capacity ratios.

In LC, when
employing a binary mixture of solvents as the mobile phase, the corrected
retention volume (V'_{a}) of a substance (a) is generally defined by
the following equation,

(36)

where (T) | is the absolute temperature |

and (c) | is the volume fraction of one component of the mobile phase |