The collective and molecular dynamics of ferroelectric liquid crystalline side group polysiloxanes has been investigated for use of broadband dielectric spectroscopy (10$+$MIN@2$/ Hz - 10$+9$/ Hz). In the lower frequency range ($LS 10$+6$/ Hz) two collective relaxations, Goldstone- and soft-mode, could be observed. They are assigned to the fluctuations of the phase and the amplitude of the helical superstructure, respectively. In the high frequency regime (10$+6$/ Hz - 10$+9$/ Hz) one dielectric relaxation, the $beta@- relaxation, is found. It is assigned to the hindered rotation (libration) of the mesogene around its long molecular axis. It shows an Arrhenius-like temperature dependence with no deviations at the phase transition S$-A$//S$+*$/$-C$/. A dilution of the mesogenes causes a decrease of the collectivity but remains the local dynamics uninfluenced.
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