In the FTIR and Raman spectroscopic studies, the phenomena of normal n-alkanes segregation in the binary mixtures of solid-state paraffin at room temperature were examined. Samples, in which one of the ingredients had been deuterated were prepared in different molar concentrations. Components of the mixture separated in time, creating separate domains, were observed in the changing of shape of infrared and Raman bands. The process of segregation depended on the difference of the chains' length of the mixture's ingredients and the molar fraction, in which the mixtures were prepared. The size of the created microdomains has been estimated based on the model describing shape and the splitting of the IR bands developed by Hiebert and Hornig. By applying the micro-Raman imaging technique, a number of surface maps have been obtained indicating the separating process of ingredients of the mixtures. This allowed comparing and verifying time dependent results of the IR study. Copyright © 2005 John Wiley & Sons, Ltd.