Atomically resolved single-molecule triplet quenching

The nonequilibrium triplet state of molecules plays an important role in photocatalysis, organic photovoltaics, and photodynamic therapy. We report the direct measurement of the triplet lifetime of an individual pentacene molecule on an insulating surface with atomic resolution by introducing an electronic pump-probe method in atomic force microscopy. Strong quenching of the triplet lifetime is observed if oxygen molecules are coadsorbed in close proximity. By means of single-molecule manipulation techniques, different arrangements with oxygen molecules were created and characterized with atomic precision, allowing for the direct correlation of molecular arrangements with the lifetime of the quenched triplet. Such electrical addressing of long-lived triplets of single molecules, combined with atomic-scale manipulation, offers previously unexplored routes to control and study local spin-spin interactions.

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Atomic Resolution with the Atomic Force Microscope

Microscopy Today ◽

10.1017/s1551929500063513 ◽

1995 ◽

Vol 3 (4) ◽

pp. 6-7

Author(s):

Stephen W. Carmichael

Keyword(s):

Atomic Force Microscopy ◽

Scanning Tunneling Microscopy ◽

Atomic Force Microscope ◽

Tracking On-Surface Chemistry with Atomic Precision

Synlett ◽

10.1055/s-0036-1590867 ◽

2017 ◽

Vol 28 (19) ◽

pp. 2509-2516 ◽

Cited By ~ 5

Author(s):

Peter Jacobse ◽

Marc-Etienne Moret ◽

Robertus Klein Gebbink ◽

Ingmar Swart

Keyword(s):

Atomic Force Microscopy ◽

Single Molecule ◽

Graphene Nanoribbons ◽

Single Molecule Level ◽

Force Microscopy ◽

The Past ◽

Atomic Force ◽

Atomic Precision ◽

Different Types ◽

Insight Into

The field of on-surface synthesis has seen a tremendous development in the past decade as an exciting new methodology towards atomically well-defined nanostructures. A strong driving force in this respect is its inherent compatibility with scanning probe techniques, which allows one to ‘view’ the reactants and products at the single-molecule level. In this article, we review the ability of noncontact atomic force microscopy to study on-surface chemical reactions with atomic precision. We highlight recent advances in using noncontact atomic force microscopy to obtain mechanistic insight into reactions and focus on the recently elaborated mechanisms in the formation of different types of graphene nanoribbons.

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Improvements in fundamental performance of in-liquid frequency modulation atomic force microscopy

Microscopy ◽

10.1093/jmicro/dfaa045 ◽

2020 ◽

Vol 69 (6) ◽

pp. 340-349

Author(s):

Takeshi Fukuma

Keyword(s):

Atomic Force Microscopy ◽

Frequency Modulation ◽

Three Dimensional ◽

Atomic Scale ◽

Atomic Resolution ◽

Scanning Method ◽

Force Microscopy ◽

Atomic Force ◽

Hydration Structure ◽

Force Resolution

Abstract In-liquid frequency modulation atomic force microscopy (FM-AFM) has been used for visualizing subnanometer-scale surface structures of minerals, organic thin films and biological systems. In addition, three-dimensional atomic force microscopy (3D-AFM) has been developed by combining it with a three-dimensional (3D) tip scanning method. This method enabled the visualization of 3D distributions of water (i.e. hydration structures) and flexible molecular chains at subnanometer-scale resolution. While these applications highlighted the unique capabilities of FM-AFM, its force resolution, speed and stability are not necessarily at a satisfactory level for practical applications. Recently, there have been significant advancements in these fundamental performances. The force resolution was dramatically improved by using a small cantilever, which enabled the imaging of a 3D hydration structure even in pure water and made it possible to directly compare experimental results with simulated ones. In addition, the improved force resolution allowed the enhancement of imaging speed without compromising spatial resolution. To achieve this goal, efforts have been made for improving bandwidth, resonance frequency and/or latency of various components, including a high-speed phase-locked loop (PLL) circuit. With these improvements, now atomic-resolution in-liquid FM-AFM imaging can be performed at ∼1 s/frame. Furthermore, a Si-coating method was found to improve stability and reproducibility of atomic-resolution imaging owing to formation of a stable hydration structure on a tip apex. These improvements have opened up new possibilities of atomic-scale studies on solid-liquid interfacial phenomena by in-liquid FM-AFM.

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Development of the UHV-STM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180367 ◽

1990 ◽

Vol 48 (1) ◽

pp. 322-323

Author(s):

M. Iwatsuki ◽

S. Kitamura ◽

A. Mogami

Keyword(s):

Surface Science ◽

Real Space ◽

Atomic Scale ◽

Scanning Tunneling ◽

Great Promise ◽

Force Microscopy ◽

Atomic Force ◽

Stm Image ◽

Surface Construction ◽

Very High

Since Binnig, Rohrer and associates observed real-space topographic images of Si(111)-7×7 and invented the scanning tunneling microscope (STM),1) the STM has been accepted as a powerful surface science instrument.Recently, many application areas for the STM have been opened up, such as atomic force microscopy (AFM), magnetic force microscopy (MFM) and others. So, the STM technology holds a great promise for the future.The great advantages of the STM are its high spatial resolution in the lateral and vertical directions on the atomic scale. However, the STM has difficulty in identifying atomic images in a desired area because it uses piezoelectric (PZT) elements as a scanner.On the other hand, the demand to observe specimens under UHV condition has grown, along with the advent of the STM technology. The requirment of UHV-STM is especially very high in to study of surface construction of semiconductors and superconducting materials on the atomic scale. In order to improve the STM image quality by keeping the specimen and tip surfaces clean, we have built a new UHV-STM (JSTM-4000XV) system which is provided with other surface analysis capability.

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Atomic Force Microscopy (AFM) for Topography and Recognition Imaging at Single Molecule Level

Encyclopedia of Biophysics ◽

10.1007/978-3-642-16712-6_496 ◽

2013 ◽

pp. 102-112

Author(s):

Memed Duman ◽

Andreas Ebner ◽

Christian Rankl ◽

Jilin Tang ◽

Lilia A. Chtcheglova ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Single Molecule ◽

Single Molecule Level ◽

Force Microscopy ◽

Atomic Force ◽

Recognition Imaging

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Atomic Force Microscopy Investigation of the Interactions between the MCM Helicase and DNA

Materials ◽

10.3390/ma14030687 ◽

2021 ◽

Vol 14 (3) ◽

pp. 687

Author(s):

Amna Abdalla Mohammed Khalid ◽

Pietro Parisse ◽

Barbara Medagli ◽

Silvia Onesti ◽

Loredana Casalis

Keyword(s):

Atomic Force Microscopy ◽

Nucleic Acid ◽

Single Molecule ◽

Protein Complex ◽

The Other ◽

Contour Length ◽

Force Microscopy ◽

Atomic Force ◽

Mcm Complex ◽

Dna Double Helix

The MCM (minichromosome maintenance) protein complex forms an hexameric ring and has a key role in the replication machinery of Eukaryotes and Archaea, where it functions as the replicative helicase opening up the DNA double helix ahead of the polymerases. Here, we present a study of the interaction between DNA and the archaeal MCM complex from Methanothermobacter thermautotrophicus by means of atomic force microscopy (AFM) single molecule imaging. We first optimized the protocol (surface treatment and buffer conditions) to obtain AFM images of surface-equilibrated DNA molecules before and after the interaction with the protein complex. We discriminated between two modes of interaction, one in which the protein induces a sharp bend in the DNA, and one where there is no bending. We found that the presence of the MCM complex also affects the DNA contour length. A possible interpretation of the observed behavior is that in one case the hexameric ring encircles the dsDNA, while in the other the nucleic acid wraps on the outside of the ring, undergoing a change of direction. We confirmed this topographical assignment by testing two mutants, one affecting the N-terminal β-hairpins projecting towards the central channel, and thus preventing DNA loading, the other lacking an external subdomain and thus preventing wrapping. The statistical analysis of the distribution of the protein complexes between the two modes, together with the dissection of the changes of DNA contour length and binding angle upon interaction, for the wild type and the two mutants, is consistent with the hypothesis. We discuss the results in view of the various modes of nucleic acid interactions that have been proposed for both archaeal and eukaryotic MCM complexes.

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Substrate Specificity of Sugar Transport by Rabbit SGLT1: Single-Molecule Atomic Force Microscopy versus Transport Studies†

Biochemistry ◽

10.1021/bi061917z ◽

2007 ◽

Vol 46 (10) ◽

pp. 2797-2804 ◽

Cited By ~ 27

Author(s):

Theeraporn Puntheeranurak ◽

Barbara Wimmer ◽

Francisco Castaneda ◽

Hermann J. Gruber ◽

Peter Hinterdorfer ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Substrate Specificity ◽

Single Molecule ◽

Sugar Transport ◽

Force Microscopy ◽

Atomic Force ◽

Transport Studies

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Breaking Down the Supramolecular Ensemble: Single-Molecule Studies of the Concentration Dependence of Main-Chain Supramolecular Polymer Molecular Weight Distributions on Surfaces

Australian Journal of Chemistry ◽

10.1071/ch09615 ◽

2010 ◽

Vol 63 (4) ◽

pp. 624

Author(s):

Michael J. Serpe ◽

Jason R. Whitehead ◽

Stephen L. Craig

Keyword(s):

Molecular Weight ◽

Single Molecule ◽

Monomer Concentration ◽

Supramolecular Polymer ◽

Force Microscopy ◽

Molecular Weight Distributions ◽

Atomic Force ◽

Multi Stage ◽

Single Molecule Studies ◽

Supramolecular Ensemble

Single molecule atomic force microscopy (AFM) studies of oligonucleotide-based supramolecular polymers on surfaces are used to examine the molecular weight distribution of the polymers formed between a functionalized surface and an AFM tip as a function of monomer concentration. For the concentrations examined here, excellent agreement with a multi-stage open association model of polymerization is obtained, without the need to invoke additional contributions from secondary steric interactions at the surface.

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