Читать книгу Chemical Analysis - Francis Rouessac - Страница 98

These parameters have been developed to pursue at least three objectives:

 To identify a compound by a more general characteristic than its retention time under predefined conditions. As a result, a system of retention indexes has been developed; it is an efficient and cheap means by which to avoid certain identification errors.

 To follow the evolution of a column’s performance over time.

 To classify all stationary phases in order to simplify the choice of the column best adapted to a particular kind of separation problem. The polarity or chemical nature of a stationary phase does not allow prediction of which column will be optimal for a given separation. For this, the behaviour of stationary phases with respect to several reference compounds should be examined, in order to determine stationary phase constants.