Coupled nuclear and electronic dynamics within a molecule are key to understanding a broad range of fundamental physical and chemical processes.Although probing the coupled vibrational and electronic dynamics was demo...Coupled nuclear and electronic dynamics within a molecule are key to understanding a broad range of fundamental physical and chemical processes.Although probing the coupled vibrational and electronic dynamics was demonstrated,it has so far been challenging to observe the coupling interactions between the rotational and electronic degrees of freedom.Here,we report the first observation of Coriolis coupling,a coupling interaction between nuclear rotational angular momentum and electronic axial angular momentum,during laser-induced molecular fragmentation by tracing the electronic structure of a dissociating O+2 molecule.We observe that the electron density changes its shape from that of a molecularσorbital to a nearly isotropic shape as the internuclear distance goes up to∼20?which results from the transition between nearly degenerate electronic states associated with different rotational angular momenta.Our experiment demonstrates that the breaking of a chemical bond does not occur suddenly during molecular dissociation.Instead,it lasts for a long time of several hundred femtoseconds due to the Coriolis coupling interaction.Our experiment can be extended to complicated molecules,holding the potential of revealing yet unobserved electron–nuclear coupling interactions during ultrafast processes.展开更多
An iterative procedure is proposed to facilitate the determination of molecular vi-brational force constants from the experimental fundamental frequencies. Proper restrictions are introduced to the force constants bas...An iterative procedure is proposed to facilitate the determination of molecular vi-brational force constants from the experimental fundamental frequencies. Proper restrictions are introduced to the force constants based on physical considerations for getting reasonable results. The experimental data of Coriolis coupling coefficients and isotopic frequency shifts are utilized to reduce the uncertainty of the calculated force constants when they are available. A series of various kinds of molecules have been calculated by this method and the results are satisfactory.展开更多
基金supported by the National Key Research and Development Program of China(grant no.2023YFA1406800)the National Natural Science Foundation of China(grant nos.62275085,12021004,11934004,and 12104063).
文摘Coupled nuclear and electronic dynamics within a molecule are key to understanding a broad range of fundamental physical and chemical processes.Although probing the coupled vibrational and electronic dynamics was demonstrated,it has so far been challenging to observe the coupling interactions between the rotational and electronic degrees of freedom.Here,we report the first observation of Coriolis coupling,a coupling interaction between nuclear rotational angular momentum and electronic axial angular momentum,during laser-induced molecular fragmentation by tracing the electronic structure of a dissociating O+2 molecule.We observe that the electron density changes its shape from that of a molecularσorbital to a nearly isotropic shape as the internuclear distance goes up to∼20?which results from the transition between nearly degenerate electronic states associated with different rotational angular momenta.Our experiment demonstrates that the breaking of a chemical bond does not occur suddenly during molecular dissociation.Instead,it lasts for a long time of several hundred femtoseconds due to the Coriolis coupling interaction.Our experiment can be extended to complicated molecules,holding the potential of revealing yet unobserved electron–nuclear coupling interactions during ultrafast processes.
基金Project supported by the National Natural Science Foundation of China.
文摘An iterative procedure is proposed to facilitate the determination of molecular vi-brational force constants from the experimental fundamental frequencies. Proper restrictions are introduced to the force constants based on physical considerations for getting reasonable results. The experimental data of Coriolis coupling coefficients and isotopic frequency shifts are utilized to reduce the uncertainty of the calculated force constants when they are available. A series of various kinds of molecules have been calculated by this method and the results are satisfactory.
