Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Controlling the identity of the tip-terminating atom or molecule in low-temperature atomic force microscopy has led to ground breaking progress in surface chemistry and nanotechnology. Lacking a comparative tip-performance assessment, a profound standardization in such experiments is highly desirable. Here we directly compare the imaging and force-spectroscopy capabilities of four atomically defined tips, namely Cu-, Xe-, CO-, and O-terminated Cu-tips (CuOx-tips). Using a nanostructured copper-oxide surface as benchmark system, we found that Cu-tips react with surface oxygen, while chemically inert Xe- and CO-tips allow entering the repulsive force regime enabling increased resolution. However, their high flexibility leads to imaging artifacts and their strong passivation suppresses the chemical contrast. The higher rigidity and selectively increased chemical reactivity of CuOx-tips prevent tip-bending artifacts and generate a distinct chemical contrast. This result is particularly promising in view of future studies on other metal-oxide surfaces.

Download full-text PDF

Source
http://dx.doi.org/10.1039/d1nr04080dDOI Listing

Publication Analysis

Top Keywords

atomically defined
8
chemical contrast
8
benchmarking atomically
4
defined afm
4
afm tips
4
tips chemical-selective
4
chemical-selective imaging
4
imaging controlling
4
controlling identity
4
identity tip-terminating
4

Similar Publications

Structure, function and assembly of nuclear pore complexes.

Nat Rev Mol Cell Biol

September 2025

Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA.

The defining property of eukaryotic cells is the storage of heritable genetic material in a nuclear compartment. For eukaryotic cells to carry out the myriad biochemical processes necessary for their function, macromolecules must be efficiently exchanged between the nucleus and cytoplasm. The nuclear pore complex (NPC) - which is a massive assembly of ~35 different proteins present in multiple copies totalling ~1,000 protein subunits and architecturally conserved across eukaryotes - establishes a size-selective channel for regulated bidirectional transport of folded macromolecules and macromolecular assemblies across the nuclear envelope.

View Article and Find Full Text PDF

Minimal Basis Iterative Stockholder Decomposition with Ellipsoidal Atoms.

J Chem Theory Comput

September 2025

Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark.

The minimal basis iterative Stockholder (MBIS) decomposition of molecular electron densities into atomic contributions is extended from spherical to ellipsoidal atomic basins. Despite the more flexible parametrization, the derived atomic multipole moments do not systematically improve the reproduction of molecular multipole moments and electrostatic potentials relative to a decomposition into spherical atomic densities. The decomposition can be constrained to exactly reproduce molecular multipole moments, in the present work extended up to hexadecapole moments, and this slightly improves the ability to reproduce the electrostatic potential.

View Article and Find Full Text PDF

The exclusive formation of artificial multicomponent assemblies remains a significant challenge, in contrast to the well-established organization observed in natural systems, due to intrinsic entropic constraints. To overcome this limitation, recent efforts have been focused on developing precision self-assembly strategies for the rational construction of such architectures. Here, we construct an ideal complementary pair of 2,2':6',2″-terpyridine (tpy)-based ligands by fine-tuning the substituent bulkiness, which enables the quantitative formation of robust nested cages through efficient dynamic heteroleptic complexation with multivalent coordination.

View Article and Find Full Text PDF

The divergence in folding pathways between RNA co-transcriptional folding (CTF) and free folding (FF) is crucial for understanding dynamic functional regulation of RNAs. Here, we developed a simplified all-atom molecular dynamics framework to systematically compare the folding kinetics of an RNA hairpin (PDB:1ZIH) under CTF and FF conditions. By analyzing over 800 microseconds of simulated trajectory, we found that despite convergence to identical native conformations across CTF simulations (with varied transcription rates) and FF simulations, they exhibit distinct preferences for the folding pathways defined by the order of base-pair formation.

View Article and Find Full Text PDF

Lanthanum-Induced Gradient Fields in Asymmetric Heterointerface Catalysts for Enhanced Oxygen Electrocatalysis.

Adv Mater

September 2025

KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.

Metal-nitrogen-carbon (M-N-C) catalysts display considerable potential as cost-effective alternatives to noble metals in oxygen electrocatalysis. However, uncontrolled atomic migration and random structural rearrangement during pyrolysis often lead to disordered coordination environments and sparse active sites, fundamentally limiting their intrinsic catalytic activities and long-term durability. Herein, a novel strategy is reported for use in directionally regulating atomic migration pathways via the incorporation of a foreign metal (La).

View Article and Find Full Text PDF