Structure, dynamics, and solvation in a disordered metal–organic coordination polymer: a multiscale study

Abstract

Metal–organic coordination polymers are a growing class of technologically-important materials in which transition metal ions are connected by multitopic organic chelators to form a 3-D network structure. While the structures of many highly-ordered metal–organic frameworks have been determined, far less structural information is available about the more common disordered materials. Our study combines pair distribution function analysis from total X-ray scattering, ab initio quantum mechanical calculations, and all-atom molecular dynamics to explore the structure and dynamics of a poorly-ordered branched coordination polymer. The polymer structure is highly flexible and dynamic, and is dramatically affected by its solvation state, a finding with far-reaching implications for the incorporation of coordination polymers into nanocomposite materials.

Keywords:

• Coordination polymer
• Molecular dynamics
• Quantum chemistry

Acknowledgments

This research was supported by grants from the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering DE-FG02-07ER46477. X-ray scattering was obtained at beamline 11-ID-B at the Advanced Photon Source (APS), Argonne National Laboratories, with the assistance of Karena Chapman. The APS is supported by the U.S. Department of Energy under Contract No. DE-AC02-06CH11357. J. Lucon was supported in part by a National Science Foundation graduate research fellowship. DFT calculations were performed on the Louisiana Optical Network Initiative (LONI) Queen Bee cluster, and MD simulations used the Texas Advanced Computing Center (TACC) Ranger cluster; both were accessed through the NSF TeraGrid infrastructure.