Structures and Structural Evolution of Sublayer Surfaces of Metal-Organic Frameworks.

The structural characterization of sublayer surfaces of MIL-101 is reported by low-dose spherical aberration-corrected high-resolution transmission electron microscopy (HRTEM). The state-of-the-art microscopy directly images atomic/molecular configurations in thin crystals from charge density projections, and uncovers the structures of sublayer surfaces and their evolution to stable surfaces regulated by inorganic Cr3 (μ3 -O) trimers. This study provides compelling evidence of metal-organic frameworks (MOFs) crystal growth via the assembly of sublayer surfaces and has important implications in understanding the crystal growth and surface-related properties of MOFs.