Accession Number:

ADA281123

Title:

Log X2 Distribution of Correlation Times Revisited

Descriptive Note:

Technical rept.

Corporate Author:

MISSOURI UNIV-ROLLA DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

1994-06-28

Pagination or Media Count:

15.0

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 polymersolvent systems can be different for the log-X2 and lognormal distributions. Due to its better defined moments, the log-normals results are believed to be more physically realistic when large widths are required. NMR, Polymers, Molecular motion, Dynamics, Correlation times.

Subject Categories:

  • Polymer Chemistry
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE