Cotton and Miller showed that the electronic part of the density matrix can be calculated within the SQC/MM framework by "binning" the trajectory to different windows which define the currently occupied electronic states in the mapping dynamics . With this method, we obtain information about the involved electronic states and transitions and can straightforwardly evaluate the DW functions of Eqs. ( ) and (32). Several comments are appropriate though. First, using the binning procedure to specify the DW functions correlates nicely with the central idea of the SQC/MM dynamics to use binning for defining the state occupations. Second, this method defines the active state in the trajectory propagation and only the diagonal elements of the density matrix are used to calculate the spectra. Therefore the current way to calculate the DW functions is very similar to that used in the on-the-fly TSH dynamics . Third, we admit limitations of the current approach. In the applications of the present work, these limitations are not crucial, because manifold I contains just a single electronic state. For molecular systems with several simultaneously excited bright electronic states in manifold I, TA PP and other nonlinear spectroscopic signals will have contributions from electronic coherences between these electronic states. The SCM/MM approach can handle these coherences, and this will require the appropriate modification of the DW algorithm. Work in this direction is currently in progress.