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arXiv · 0812.2391

Direct conversion of rheological compliance measurements into storage and loss moduli

R M L Evans·Manlio Tassieri·Dietmar Auhl·Thomas A Waigh
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Abstract

We remove the need for Laplace/inverse-Laplace transformations of experimental data, by presenting a direct and straightforward mathematical procedure for obtaining frequency-dependent storage and loss moduli ($G'(ω)$ and $G"(ω)$ respectively), from time-dependent experimental measurements. The procedure is applicable to ordinary rheological creep (stress-step) measurements, as well as all microrheological techniques, whether they access a Brownian mean-square displacement, or a forced compliance. Data can be substituted directly into our simple formula, thus eliminating traditional fitting and smoothing procedures that disguise relevant experimental noise.

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R M L Evans, Manlio Tassieri, Dietmar Auhl, Thomas A Waigh. 2008-12-12. Direct conversion of rheological compliance measurements into storage and loss moduli. https://doi.org/10.1103/physreve.80.012501

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