reciprocal distance matrix and named the Harary index in honor of Professor Frank Harary,
has been introduced. The Harary index is not a unique molecular descriptor; the smallest
pair of the alkane trees with identical Harary indices has been detected in the octane family.
The use of the Harary index in the quantitative structure-property relationships is exemplified
in modeling physical properties of the C 2-C 9 alkanes. In this application, the performance …