Accession Number : AD0288939

Title :   THE ATTRACTIVE FORCES BETWEEN LONG SATURATED CHAINS AT SHORT DISTANCES

Corporate Author : HARVARD UNIV CAMBRIDGE MASS

Personal Author(s) : SALEM,LIONEL

Report Date : DEC 1962

Pagination or Media Count : 1

Abstract : The assumption of locally additive forces is used to describe the London-Van der Waals dispersion attraction between long saturated chains at distances small in comparison with their length. A formula for the total dispersion energy is presented for two linear chains of length L, opposed and parallel, each built out of N identical units of length. At distances D (mutual distance of the 2 chains) much smaller than the molecular length L the energy becomes proportional to L (or N) and inversely proportional to the fifth power of the intermolecular distance. The coefficient A is calculated for the interaction between two CH2 units in hydrocarbon chains and the result is used to estimate the sublimation energy at 0 K of paraffin crystals. Sound agreement with experiment was obtained. Particularities of the attractive forces between long saturated chains are examined in detail and their great sensitivity to distance is shown. Various applications to systems of biological interest are suggested. (Author)

Descriptors :   (*CHEMICAL BONDS), (*HYDROCARBONS), (*MOLECULES), (*QUANTUM MECHANICS), CRYSTAL LATTICES, ELECTRONS, ENERGY, FILMS, MATHEMATICAL ANALYSIS

Distribution Statement : APPROVED FOR PUBLIC RELEASE