Interpretation of IR spectra using complete sets of structure fragment compositions and an IR search system. 3. Analysis of large fragments

The results of identification of five-, six-, and seven-node fragments by the IR spectra of compounds are characterized by quantitative parameters: probability, reliability, and types of fragments. This analysis is carried out using the database containing more than 11,000 complete IR spectra and structures of organic compounds. It is analyzed how the fractions of correct fragments in the search result depend on the threshold occurrence and nonrandomness of fragment selection. Examples of statistical reliability of the revealed fragments are given. Translated fromZhumal Struktumoi Khimii, Vol. 38, No. 2, pp. 369–379, March–April, 1997.