Crystal flex bases and the RUM spectrum

  title={Crystal flex bases and the RUM spectrum},
  author={Ghada Badri and Derek Kitson and S. C. Power},
  journal={Proceedings of the Edinburgh Mathematical Society},
  pages={735 - 761}
A theory of infinite spanning sets and bases is developed for the first-order flex space of an infinite bar-joint framework, together with space group symmetric versions for a crystallographic bar-joint framework ${{\mathcal {C}}}$. The existence of a crystal flex basis for ${{\mathcal {C}}}$ is shown to be closely related to the spectral analysis of the rigid unit mode (RUM) spectrum of ${{\mathcal {C}}}$ and an associated geometric flex spectrum. Additionally, infinite spanning sets and bases… 
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