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Resolving individual atoms has always been the ultimate goal of surface microscopy. The scanning tunneling microscope images atomic-scale features on surfaces, but resolving single atoms within an adsorbed molecule remains a great challenge because the tunneling current is primarily sensitive to the local electron density of states dose to the Fermi level. We demonstrate imaging of molecules with unprecedented atomic resolution by probing the short-range chemical forces with use of noncontact atomic force microscopy. The key step is functionalizing the microscope's tip apex with suitable, atomically well-defined terminations, such as CO molecules. Our experimental findings are corroborated by ab initio density functional theory calculations. Comparison with theory shows that Pauli repulsion is the source of the atomic resolution, whereas van der Waals and electrostatic forces only add a diffuse attractive background.

Layered clays are of scientific and technological interest because of their use as ion-exchange materials (1), catalysts (2), antacids (3), catalytic supports (4), and modified electrodes (5). The observation that [...]

Langmuir-Blodgett films of barium arachidate have been studied on both macroscopic and microscopic scales by atomic force microscopy. As prepared, the films exhibit a disordered hexagonal structure; molecularly resolved images [...]

A LARGE NUMBER OF INDUSTRIAL and natural processes involve the dissolution and growth of crystals from aqueous solutions. Crystals are synthetically grown for use as electronic components, gems, reagents, and [...]

Imaging and Manipulating Molecules on a Zeolite Surface with an Atomic Force Microscope ZEOLITES ARE CRYSTALLINE ALUminosilicates that have a regular pore or channel structure on the order of atomic [...]

With an atomic force microscope operating in the noncontact mode in an ultrahigh vacuum, atomic-resolution imaging of the cleaved semi-insulating InP(110) surface has been achieved. By this method, atomic scale point defects and their motion were observed at room temperature, without the field-induced effects associated with scanning tunneling microscopy., The ability to resolve individual atoms over a wide area makes the scanning tunneling microscope (STM) an excellent tool for studying the migration of atoms or defects. However, in all [...]

Results of studies on the interaction between the tip of an atomic force microscope and polystyrene molecules in a film spread on a surface are reported. The tip produces a persistent deformation on the film; some of the polyner molecules are eventually pulled up by the tip. Nanometer-size structures are induced, resulting in a pattern that is periodic and is oriented perpendicular to the scan direction., The atomic force microscope (AFM) [1] has found application in a variety of surface studies including atomic scale friction [2, 3], elasticity [4], and surface forces [4, 5] but has [...]

The imaging of living specimens in water by x-ray microscopy can be greatly enhanced with the use of an intense flash x-ray source and sophisticated technologies for reading x-ray images. [...]

Defects in the layering of Langmuir-Blodgett (LB) films can be eliminated by depositing from the appropriate monolayer phase at the air-water interface. LB films deposited from the hexagonal phase of cadmium arachidate ([CdA.sub.2]) at pH 7 spontaneously transform into the bulk soap structure, a centrosymmetric bilayer with an orthorhombic herringbone packing. A large wavelength folding mechanism accelerates the conversion between the two structures, leading to a disruption of the desired layering. At pH [is greater than] 8.5, though it is more difficult to draw LB films, almost perfect layering is obtained due to the inability to convert from the as-deposited structure to the equilibrium one., Langmuir-Blodgett films are made by pulling a substrate through a monolayer of amphiphilic molecules at the air-water interface. Under the appropriate conditions, the monolayer is transferred to the substrate (1, [...]

Imagine yourself at a fruit stand, with a blindfold over your eyes. You could probably identify various fruits by touching them, even using only one hand. Now imagine that you [...]

We report the specific transduction, via surface stress changes, of DNA hybridization and receptor-ligand binding into a direct nanomechanical response of microfabricated cantilevers. Cantilevers in an array were functionalized with a selection of biomolecules. The differential deflection of the cantilevers was found to provide a true molecular recognition signal despite large nonspecific responses of individual cantilevers. Hybridization of complementary oligonucleotides shows that a single base mismatch between two 12-mer oligonucleotides is dearly detectable. Similar experiments on protein A-immunoglobulin interactions demonstrate the wide-ranging applicability of nanomechanical transduction to detect biomolecular recognition., In recent years, biomolecules and their unique ability of molecular recognition have been investigated in terms of their mechanical response to external forces. A common feature of methods such as [...]

Before the advent of the atomic force microscope (AFM), students of protein folding who wanted to unfold a protein had either to heat it or expose it to chemical denaturants, [...]

Imaging Crystals, Polymers, and Processes in Water with the Atomic Force Microscope THE ATOMIC FORCE MICROSCOPE (AFM) gives topographic images by scanning a sharp tip over a surface and has [...]