Dynamics of proton spin-lattice relaxation in glycerol

Autor: Marko Patrick John Punkkinen, E. Koivula, W. H. Tanttila, E.E. Ylinen
Rok vydání: 1985
Předmět:
Zdroj: Physical Review B. 32:4556-4564
ISSN: 0163-1829
DOI: 10.1103/physrevb.32.4556
Popis: We have measured the temperature dependence of the proton spin-lattice relaxation time ${\mathit{T}}_{1}$ in glycerol in the temperature range 5--300 K. The lattice dynamics responsible for the relaxation in the range 5T160 K is calculated using solitons with a formation energy \ensuremath{\Delta}/k=1 K. In the range 220T300 K the dynamics of the lattice includes solitons with a formation energy \ensuremath{\Delta}/k=4200 K and these are used to calculate the relaxation of the protons. In both temperature ranges the heat capacity, thermal expansion, and heat conduction are calculated using the same parameters for the soliton representation as were used to calculate the temperature dependence of the proton spin-lattice relaxation time. Discontinuities in the thermal properties at the glass transition temperature ${\mathit{T}}_{\mathit{g}}$ are attributed to an effective-mass change of the low-energy solitons. This work was conducted to test, with the use of nuclear magnetic resonance, some recent ideas in the dynamics of amorphous materials.
Databáze: OpenAIRE