Application of Recurrence Relations to Melting Points of Homologs

摘要

The previously established recurrence equations A(n+1)=aA(n)+b characterizing variations in the majority of physicochemical constants of organic compounds in homologous series and relating the properties of adjacent homologs with n+1 and n carbon atoms are applicable in the modified form [T_m(n+2)= aT_m+b] to the melting points.This second-order recurrence is observed with a high accuracy,despite sig- nificant alternations in the melting points of even and odd homologs.The method for calculating melting points,based on this recurrence,has no analogs among the previously suggested methods and makes it pos- sible,in particular,to reveal errors in reference data,originating in most cases from the low purity of the samples dealt with.