Journal article
Sedimentation of C60 and C70: Testing the Limits of Stokes' Law
J Pearson, TL Nguyen, H Cölfen, P Mulvaney
Journal of Physical Chemistry Letters | AMER CHEMICAL SOC | Published : 2018
Abstract
Virtually all dynamic methods for determining particle size on the nanoscale use the Stokes-Einstein-Sutherland (SES) equation to convert the diffusion coefficient into a hydrodynamic radius. The validity of this equation on the nanoscale has not been rigorously validated by experiment. Here we measure the sedimentation rates and diffusion coefficients of C60 and C70 in toluene using analytical ultracentrifugation and compare the results to the SES equation. We find that the SES equation for the drag force (nonslip boundary condition) works down to 1 nm length scales.
Grants
Awarded by Australian Research Council
Funding Acknowledgements
We thank Wallace Wong for the fullerene samples. P.M. thanks the ARC for support through centre grant CE170100026. H.C. and J.P. acknowledge support by Deutsche Forschungsgemeinschaft (SFB 1214, Project B6) and the Center for Advanced Photonics (CAP) at the University of Konstanz.