mobility (general)

https://doi.org/10.1351/goldbook.MT06760
Mass transport is described by a mobility \(b\), defined by: \[b_{i} = \frac{\nu _{i}}{\boldsymbol{F}_{i}}\] where \(\nu _{i}\) is the average drift velocity and \(\boldsymbol{F}_{i}\) is the force on particle \(i\).
Source:
PAC, 1999, 71, 1307. (Definitions of Terms for Diffusion in the Solid State) on page 1319 [Terms] [Paper]