Regulating the Electronic Structure of Metal Nanoclusters by Longitudinal Single-Dithiolate Substitution

It is significant but challenging to understand the property
evolution
of metal nanoclusters by orientated regulation of the electronic structure.
Previous research has demonstrated that the optical properties of
metal nanoclusters with anisotropic structures are greatly impacted
by their longitudinal electronic structure. However, the manipulation
of optical properties of metal nanoclusters by regulating their electronic
structure through longitudinal dithiolate substitutions has not yet
been reported. In this study, we first achieved the longitudinal single-dithiolate
replacement of metal nanoclusters and obtained two novel nanoclusters:
Au28(SPh-tBu)18(SCH2SCH2S) and Au28(SPh-tBu)18(SCH2CH2CH2S). Both experimental and theoretical results demonstrated the regulation
of the electronic structure (dipole moment) in the z (longitudinal) and x directions, resulting in absorption
redshift and photoluminescence (polarity) enhancement. These findings
not only deepen the understanding of the property–electronic
structure correlation of metal nanoclusters but also provide guidance
for their subtle property tuning.