I had the privilege and the pleasure to work closely with Stephen J. Pennycook for about twenty years, having a group of post-docs and Vanderbilt-University graduate students embedded in his electron microscopy group ...I had the privilege and the pleasure to work closely with Stephen J. Pennycook for about twenty years, having a group of post-docs and Vanderbilt-University graduate students embedded in his electron microscopy group at Oak Ridge National Laboratory, spending on average a day per week there. We combined atomic-resolution imaging of materials,electron-energy-loss spectroscopy, and density-functional-theory calculations to explore and elucidate diverse materials phenomena, often resolving long-standing issues. This paper is a personal perspective of that journey, highlighting a few examples to illustrate the power of combining theory and microscopy and closing with an assessment of future prospects.展开更多
Excited-state hydrogen bond strongly affects the intramolecular charge conversion process,which is very suitable for the design and development of high-performance fluorescent probes.However,as one of the most common ...Excited-state hydrogen bond strongly affects the intramolecular charge conversion process,which is very suitable for the design and development of high-performance fluorescent probes.However,as one of the most common solvents or additives used in sensing,the role of dimethyl sulfoxide(DMSO)in the system of the excited-state hydrogen bond is seldom explored.As the goal of this research,we investigated the sensing mechanism of a C0RM3-green fluorescent probe system for carbon monoxide releasing molecule(CORM-3)detection and tracking in vivo,through quantum chemistry calculations based on density-functional-theory(DFT)/time-dependent density-functional-theory(TDDFT)methods.Based on the analysis of the solvent effect of DMSO by the reduced density gradient function and IR spectroscopy,we provided a new strategy to explain the fluorescence mechanism.Subsequently,we verified the result through the potential energy curve of Phthalimide(PTI,the reduced product of C0RM3-green).The excited-state hydrogen bond between PTI and DMSO promotes radiation transition and leads to obvious difference in the photophysical properties of PTI and PTI-DMSO.展开更多
文摘I had the privilege and the pleasure to work closely with Stephen J. Pennycook for about twenty years, having a group of post-docs and Vanderbilt-University graduate students embedded in his electron microscopy group at Oak Ridge National Laboratory, spending on average a day per week there. We combined atomic-resolution imaging of materials,electron-energy-loss spectroscopy, and density-functional-theory calculations to explore and elucidate diverse materials phenomena, often resolving long-standing issues. This paper is a personal perspective of that journey, highlighting a few examples to illustrate the power of combining theory and microscopy and closing with an assessment of future prospects.
基金the National Natural Science Foundation of China(Nos.21775116 and 21922411)DICP Innovation Funding(No.DICP-RC201801)the Liaoning Revitalization Talents Program(No.XLVC1802109).
文摘Excited-state hydrogen bond strongly affects the intramolecular charge conversion process,which is very suitable for the design and development of high-performance fluorescent probes.However,as one of the most common solvents or additives used in sensing,the role of dimethyl sulfoxide(DMSO)in the system of the excited-state hydrogen bond is seldom explored.As the goal of this research,we investigated the sensing mechanism of a C0RM3-green fluorescent probe system for carbon monoxide releasing molecule(CORM-3)detection and tracking in vivo,through quantum chemistry calculations based on density-functional-theory(DFT)/time-dependent density-functional-theory(TDDFT)methods.Based on the analysis of the solvent effect of DMSO by the reduced density gradient function and IR spectroscopy,we provided a new strategy to explain the fluorescence mechanism.Subsequently,we verified the result through the potential energy curve of Phthalimide(PTI,the reduced product of C0RM3-green).The excited-state hydrogen bond between PTI and DMSO promotes radiation transition and leads to obvious difference in the photophysical properties of PTI and PTI-DMSO.