Heterometal-Doped M<sub>23</sub> (M = Au/Ag/Cd) Nanoclusters with Large Dipole Moments.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 32286795.
- Also identified by DOI 10.1021/acsnano.0c01000.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Dipole moment (μ) is a critical parameter for molecules and nanomaterials as it affects many properties. In metal-thiolate (SR) nanoclusters (NCs), μ is commonly low (0-5 D) compared to quantum dots. Herein, we report a doping strategy to give giant dipoles (∼18 D) in M<sub>23</sub> (M = Au/Ag/Cd) NCs, falling in the experimental trend for II-VI quantum dots. In M<sub>23</sub> NCs, high μ is caused by the Cd-Br bond and the arrangement of heteroatoms along the <i>C</i><sub>3</sub> axis. Strong dipole-dipole interactions are observed in crystalline state, with energy exceeding 5 kJ/mol, directing a "head-to-tail" alignment of Au<sub>22-<i>n</i></sub>Ag<sub><i>n</i></sub>Cd<sub>1</sub>(SR)<sub>15</sub>X (SR = adamantanethiolate) dipoles. The alignment can be controlled by <i>μ via</i> doping. The optical absorption peaks of M<sub>23</sub> show solvent polarity-dependent shifts (∼25 meV) with negative solvatochromism. Detailed electronic structures of M<sub>23</sub> are revealed by density functional theory and time-dependent DFT calculations. Overall, the doping strategy for obtaining large dipole moments demonstrates an atomic-level design of clusters with useful properties.