[Application of Verloop parameters. Comparison with other steric parameters and problems of choice of parameter]

Verloop's steric parameters. L, B1, B2, B3, B4, were tested in five groups of molecules, generally successfully, These were compared with classical steric parameters: indices of molecular connectivity, Taft's Es parameter, Van der Waals radii and molecular refraction. Some rules have been developed to decide which parameters to use for various types of substituent.