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Why are Empower GPC Mn and Mw calculations done differently than in other software packages? - WKB4163

Article number: 4163

ENVIRONMENT

  • Empower 3

ANSWER

  • Empower does not use the formulas with the number of molecules in a slice (Ni) because it is not directly measurable with GPC
  • Instead, it uses the formulas with Ci because concentration is directly measured by the detector
  • Empower defaults to using slice area as the concentration (Ci) variable in its formulas

ADDITIONAL INFORMATION

  • Empower calculates the molecular weight averages as detailed in the following book:
    • An Introduction to Separation Science; by Barry L. Karger, Lloyd R. Snyder, and Kasaba Horvath; Copyright 1973 by John Wiley & Sons, Inc.; Determination of Molecular Weights and Molecular Weight Distribution, pages 458-461.
  • Follow the link to view the applicable pages from the reference:  GPC Reference pages

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