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.
@article{arxiv.0812.2391,
title = {Direct conversion of rheological compliance measurements into storage and loss moduli},
author = {R M L Evans and Manlio Tassieri and Dietmar Auhl and Thomas A Waigh},
journal= {arXiv preprint arXiv:0812.2391},
year = {2009}
}