Predicting Segregation Energy in Single Atom Alloys Using Physics and Machine Learning.

Single atom alloys (SAAs) show great promise as catalysts for a wide variety of reactions due to their tunable properties, which can enhance the catalytic activity and selectivity. To design SAAs, it is imperative for the heterometal dopant to be stable on the surface as an active catalytic site. One main approach to probe SAA stability is to calculate surface segregation energy.

Correlating structural rules with electronic properties of ligand-protected alloy nanoclusters.

Thiolate protected gold nanoclusters (TPNCs) are a unique class of nanomaterials finding applications in various fields, such as biomedicine, optics, and catalysis. The atomic precision of their structure, characterized through single crystal x-ray diffraction, enables the accurate investigation of their physicochemical properties through electronic structure calculations. Recent experimental efforts have led to the successful heterometal doping of TPNCs, potentially unlocking a large domain of bimetallic TPNCs for targeted applications.

Predicting ligand removal energetics in thiolate-protected nanoclusters from molecular complexes.

Thiolate-protected metal nanoclusters (TPNCs) have attracted great interest in the last few decades due to their high stability, atomically precise structure, and compelling physicochemical properties. Among their various applications, TPNCs exhibit excellent catalytic activity for numerous reactions; however, recent work revealed that these systems must undergo partial ligand removal in order to generate active sites. Despite the importance of ligand removal in both catalysis and stability of TPNCs, the role of ligands and metal type in the process is not well understood.

Atom-by-Atom Evolution of the Same Ligand-Protected Au, Au, AuCd, and Au Nanocluster Series.

Atom-by-atom manipulation on metal nanoclusters (NCs) has long been desired, as the resulting series of NCs can provide insightful understanding of how a single atom affects the structure and properties as well as the evolution with size. Here, we report crystallizations of Au(SAdm) and AuCd(SAdm) (SAdm = adamantanethiolate) which link up with Au(SAdm) and Au(SAdm) NCs and form an atom-by-atom evolving series protected by the same ligand. Structurally, Au(SAdm) has an Au(SAdm) surface motif which is longer than the Au(SAdm) on Au(SAdm), whereas AuCd(SAdm) lacks one staple Au atom compared to Au(SAdm) and thus the surface structure is reconstructed.

Towards elucidating structure of ligand-protected nanoclusters.

Ligand-protected metal nanoclusters (NCs) are organic-inorganic nanostructures, exhibiting high stability at specific "magic size" compositions and tunable properties that make them promising candidates for a wide range of nanotechnology-based applications. Synthesis and characterization of these nanostructures has been achieved with atomic precision, offering great opportunities to study the origin of new physicochemical property emergence at the nanoscale using theory and computation. In this Frontier article, we highlight the recent advances in the field of ligand-protected metal NCs, focusing on stability theories on monometallic and heterometal doped NCs, and NC structure prediction.

Rapid Prediction of Bimetallic Mixing Behavior at the Nanoscale.

The nanoparticle (NP) design space allows for variations in size, shape, composition, and chemical ordering. In the search for low-energy structures, this results in an extremely large search space which cannot be screened by brute force methods. In this work, we develop a genetic algorithm to predict stable bimetallic NPs of any size, shape, and metal composition.

Heterometal-Doped M (M = Au/Ag/Cd) Nanoclusters with Large Dipole Moments.

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 (M = Au/Ag/Cd) NCs, falling in the experimental trend for II-VI quantum dots.

Structure-property relationships on thiolate-protected gold nanoclusters.

Since their discovery, thiolate-protected gold nanoclusters (Au (SR) ) have garnered a lot of interest due to their fascinating properties and "magic-number" stability. However, models describing the thermodynamic stability and electronic properties of these nanostructures as a function of their size are missing in the literature. Herein, we employ first principles calculations to rationalize the stability of fifteen experimentally determined gold nanoclusters in conjunction with a recently developed thermodynamic stability theory on small Au nanoclusters (≤102 Au atoms).

Haploinsufficiency leads to neurodegeneration in C9ORF72 ALS/FTD human induced motor neurons.

An intronic GGGGCC repeat expansion in C9ORF72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), but the pathogenic mechanism of this repeat remains unclear. Using human induced motor neurons (iMNs), we found that repeat-expanded C9ORF72 was haploinsufficient in ALS. We found that C9ORF72 interacted with endosomes and was required for normal vesicle trafficking and lysosomal biogenesis in motor neurons.