Abstract
Precise measurements of the complex permittivity of acetone at 293 K have been made for frequencies in the range 50–310 GHz. These, when obtained with earlier results, have allowed for a determination of the complex permittivity over the entire 0–6 THz frequency region. The results suggest the presence of a dynamic cooperative motion among the acetone molecules in the pure liquid. The experimental data are fitted to the Budó model and confined rotator models (CRM). Both models are shown to have their own characteristic features. The Budó model provides a better fit for low and high frequencies, whereas the CRM provides a better fit for middle frequencies only.