Static disorder and local structure in zinc(II) isonicotinate, a quartzlike metal–organic framework
I E Collings, M G Tucker, D A Keen and A L Goodwin
Z Krist 227, 313-320 (2012)
The final authors’ version of this article is available open access via. arXiv.org.
Using a combination of Rietveld and RMC refinement of neutron total scattering data, we find that the 10 K structure of zinc(II) isonicotinate shows strong evidence of static disorder. This disorder takes the form of transverse displacements of the isonicotinate ligand and results in elongated atomic displacement parameters and dampened oscillations of the experimental G(r). We analyse the RMC configurations using an approach derived from geometric algebra. Complications regarding the inclusion of hydrogenous guest molecules within the pore structure are discussed. This study highlights the way in which structural flexibility can give rise to multiple low-energy ground states in MOF-type materials.