Vibrational Modes and Terahertz Physical Phenomena Underpinning ZIF-71 Metal-Organic Framework.

The zeolitic imidazole framework ZIF-71 has the potential to outperform other well-studied metal-organic frameworks due to its intrinsic hydrophobicity and large pore size. However, a detailed description of its complex physical phenomena and structural dynamics has been lacking thus far. Herein, we elucidated all vibrational modes of ZIF-71 using high-resolution inelastic neutron scattering and synchrotron radiation infrared spectroscopy in conjunction with density functional theory calculations. We discover low-energy collective modes, such as gate-opening and shearing mechanisms that may affect the functions and framework stability of ZIF-71. Its single-crystal mechanical properties are further unraveled by nanoscale analytics.