Benchmark Dynamics of Dipolar Molecular Rotors in Fluorinated Metal-Organic Frameworks.
Benchmark Dynamics of Dipolar Molecular Rotors in Fluorinated Metal-Organic Frameworks.
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氟化金属有机框架中偶极分子转子的基准动力学。
DOI：
10.1002/anie.202215893
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发表时间：
2022
影响因子：
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通讯作者：
A. Comotti
中科院分区：
文献类型：
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作者：
J. Perego;C. Bezuidenhout;S. Bracco;S. Piva;G. Prando;Cristian Aloisi;P. Carretta;Jiří Kaleta;Thi;P. Sozzani;A. Daolio;A. Comotti
氟化金属有机框架（MOFs），由轮形配体与双旋转氟原子组成，在2k下产生相关偶极转子的基准迁移率，活化能几乎为零（Ea = 17 cal/mol）。由于相关偶极子-转子构型之间的交换，1H - T1核磁共振揭示了多重弛豫现象。同步辐射x射线衍射，密度泛函理论，分子动力学和声子计算显示了流体景观，并指出了偶极子构型相互转化的级联机制。超极化氙核磁共振显示的气体可接近性允许化学刺激干预：CO2触发偶极子重定向，降低它们的集体动力学并刺激晶体中的偶极子构型变化。动态材料具有有限的热噪声和高响应性，可以制造低能量耗散和动态可控的分子机器。
Fluorinated Metal-Organic Frameworks (MOFs), comprising a wheel-shaped ligand with geminal rotating fluorine atoms, produced benchmark mobility of correlated dipolar rotors at 2 K, with practically null activation energy (Ea = 17 cal/mol). 1H T1 NMR revealed multiple relaxation phenomena due to the exchange among correlated dipole-rotor configurations. Synchrotron radiation X-ray diffraction at 4 K, Density Functional Theory, Molecular Dynamics and phonon calculations showed the fluid landscape and pointed out a cascade mechanism converting dipole configurations into each other. Gas accessibility, shown by hyperpolarized-Xe NMR, allowed for chemical stimuli intervention: CO2 triggered dipole reorientation, reducing their collective dynamics and stimulating a dipole configuration change in the crystal. Dynamic materials under limited thermal noise and high responsiveness enable the fabrication of molecular machines with low energy dissipation and controllable dynamics.