A ferrocene based switchable molecular folding ruler.

@article{Scottwell2017AFB,
  title={A ferrocene based switchable molecular folding ruler.},
  author={Syn\ove \O Scottwell and Jonathan E. Barnsley and Christopher John McAdam and Keith C Gordon and James D Crowley},
  journal={Chemical communications},
  year={2017},
  volume={53 54},
  pages={7628-7631}
}
A 2,2'-bipyridine-appended bis(ferrocene) three tiered molecular folding ruler, can be switched from a folded conformation to an extended conformation by the addition of [Cu(CH3CN)4](PF6) and 6,6'-dimesityl-2,2'-bipyridine. This extension and contraction process could be triggered either chemically or electrochemically and was reversible.