Accession Number : ADA138874

Title :   Thermodynamics of Dimerization of Lithium Salts in 1,2 Dimethoxyethane.

Descriptive Note : Technial rept. Jun-Dec 83,


Personal Author(s) : Maaser,H E ; Delsignore,M ; Petrucii,S

PDF Url : ADA138874

Report Date : 05 Jan 1984

Pagination or Media Count : 35

Abstract : Electrical conductance data in the concentration range .0001 to .01 for LiBF4 in 1,2-DME are interpreted by the Fuoss-Kraus theory yielding values of the ion-pairs and triple-ions formation constants. Complex dielectric permittivities for LiBF4 in 1,2-DME at 25 C in the frequency range 0.9-81 GHz are reported. The data are interpreted by two Debye relaxation processes, one for the solvent and one for the solute. The latter is interpreted as due to the diffusional rotation of ion-pairs. Ultrasonic absorption data for LiBF4 in 1,2-DME at 25 C in the concentration range 0.28-0.55M and frequency range 10-550 MHz are reported. The data are described by a single Debye relaxation process and are interpreted as due to an ion-pair dimerization equilibrium leading to formation of quadrupoles. Theoretical expression (similar to the ones of Fuoss and Bjerrum for ion-pairs) are developed for the dimerization of ion pairs to quadrupoles. To this end, a point dipole-point dipole potential has been used. The dependence of K sub F nd K sub Bj from the dipole-dipole separation distance is illustrated. Further, the thermodynamic increments delta V sub T, delta S sub o, delta H sub o and delta V sub s have been calculated.

Descriptors :   *Lithium compounds, *Salts, *Thermodynamics, *Electrical conductivity, *Dielectric properties, Ultrasonics, Absorption, Microwaves, Relaxation, Dimers, Ethers, Ions, Dipole moments, Chelation, Chlorine compounds, Boron compounds, Fluorides

Subject Categories : Physical Chemistry
      Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE