Log X2 Distribution of Correlation Times Revisited
Abstract
The log-X2 distribution of correlation times and its application to polymer systems are examined. It is found that the original mean correlation- time parameter, T sub o, (Macromolecules, 1973, 6, 882) does not represent the true mean of the distribution. A properly parameterized log 2 distribution and function relating the original T sub o and width parameters, p and b, to the true mean are derived. Fitting of both the original log-X2, corrected log-X2, and log-normal distribution to experimental data is discussed and the log-normal distribution being proposed as an alternative. Interpretations of NMR data from polymer/solvent systems can be different for the log-X2 and lognormal distributions. Due to its better defined moments, the log-normal's results are believed to be more physically realistic when large widths are required. NMR, Polymers, Molecular motion, Dynamics, Correlation times.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 28, 1994
- Accession Number
- ADA281123
Entities
People
- Frank D. Blum
- Robert D. O'connor