Disordered Arrangements of Guest Molecules in CO Clathrate Hydrates

Abstract

CO molecules taken up in clathrate hydrates with structures I and II show highly disordered arrangements, which are hard to analyze by classical methods for structure refinement adopting split-atom models. Rietveld refinements followed by maximum entropy method analyses from TOF neutron powder diffraction data of CO clathrate hydrates made it possible to visualize doughnut- and die-like distributions of CO molecules in 5¹² and 5¹²6⁴ cages, respectively.