Due to the tremendous applications of the plasmon resonance
excitation
process, such as improvements in catalytic efficiency due to plasmonic
enhancement and/or hot-electron processes, understanding the mechanism
behind these processes has become a popular topic in recent years.
In this work, we focus on unraveling the mechanism of excitation-induced
H2 activation using a simplified triangular Au6/Ag6 cluster to investigate the effects of the electric
field on electron redistribution and bond activation. We applied both
static and continuous wave fields to investigate how these fields
affect the systems. Geometrical changes (such as bond lengthening),
molecular orbital reordering (affecting the relative energies of orbitals
corresponding to hot-electron and charge-transfer excited states),
and electronic charge redistribution between the cluster and the adsorbate
occur upon application of a static electric field. To study H2 activation, we apply Ehrenfest dynamics with real-time time-dependent
density functional theory and examine how different excitation frequencies
and polarizations affect bond activation. Moreover, electron-only
dynamics are examined with real-time time-dependent density functional
theory, and the time-dependent variations in the orbital populations
and electronic transitions provide information about the excitation
and relaxation processes of hot electrons with applied electric fields.
The static field results represent structures that can be accessed
during the evolution of the systems when applying continuous wave
fields. Through these studies, the effects of static and continuous
wave field effects on plasmon-induced H2 activation can
be understood.