Definition of configurational Isomer
Configurational Isomer is another kinds of Stereoisomer that depends on the different configuration of the asymetric carbon. Configurational Isomer is also called Inversion Isomer. The superimpossibility and interconvertability is the common parameter of identifying the configurational isomer or conformational isomer. Non superimpose structures are isomers. After rotation if they are non superimpose, they are non interconvertable. Hence, these are configuratuonal Isomers. But if these two structure if Isomers are superimpose after rotation of single bond, thesr may define as conformarional isomer. The superimposing and interconverting test can differ configurational isomer from conformational isomer.
Configuration means the arrangement of atom. In the structure of sec butyl chloride there have two arrangement of atoms in src butyl chloride. These are the Isomers. Between these two arrangements, one rotates plane polarized light to the right and others rotate plane polarized light to the left. Superimposibility test of the two arrangement of sec butyl chloride indicates that these are configurational isomers.