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Cellular solids (e.g., foams and honeycombs) are widely found in natural and engineering systems because of their high mechanical efficiency and tailorable properties. While these materials are often based on polycrystalline or amorphous constituents, here we report an unusual dual-scale, single-crystalline microlattice found in the biomineralized skeleton of the knobby starfish, Protoreaster nodosus. This structure has a diamond-triply periodic minimal surface geometry (lattice constant, approximately 30 micrometers), the [111] direction of which is aligned with the c-axis of the constituent calcite at the atomic scale. This dual-scale crystallographically coaligned microlattice, which exhibits lattice-level structural gradients and dislocations, combined with the atomic-level conchoidal fracture behavior of biogenic calcite, substantially enhances the damage tolerance of this hierarchical biological microlattice, thus providing important insights for designing synthetic architected cellular solids. [ABSTRACT FROM AUTHOR]

Understanding spin-lattice coupling represents a key challenge in modern condensed matter physics, with crucial importance and implications for ultrafast and two-dimensional magnetism. The efficiency of angular momentum and energy transfer between spins and the lattice imposes fundamental speed limits on the ability to control spins in spintronics, magnonics, and magnetic data storage. We report on an efficient nonlinear mechanism of spin-lattice coupling driven by terahertz light pulses. A nearly single-cycle terahertz pulse resonantly interacts with a coherent magnonic state in the antiferromagnet cobalt difluoride (CoF2) and excites the Raman-active terahertz phonon. The results reveal the distinctive functionality of antiferromagnets that allows ultrafast spin-lattice coupling using light. [ABSTRACT FROM AUTHOR]

Single-crystal metals have distinctive properties owing to the absence of grain boundaries and strong anisotropy. Commercial single-crystal metals are usually synthesized by bulk crystal growth or by deposition of thin films onto substrates, and they are expensive and small. We prepared extremely large single-crystal metal foils by “contact-free annealing” from commercial polycrystalline foils. The colossal grain growth (up to 32 square centimeters) is achieved by minimizing contact stresses, resulting in a preferred in-plane and out-of-plane crystal orientation, and is driven by surface energy minimization during the rotation of the crystal lattice followed by “consumption” of neighboring grains. Industrial-scale production of single-crystal metal foils is possible as a result of this discovery. [ABSTRACT FROM AUTHOR]

In modern microelectronic devices, hot electrons accelerate, scatter, and dissipate energy in nanoscale dimensions. Despite recent progress in nanothermometry, direct real-space mapping of hot-electron energy dissipation is challenging because existing techniques are restricted to probing the lattice rather than the electrons. We realize electronic nanothermometry by measuring local current fluctuations, or shot noise, associated with ultrafast hot-electron kinetic processes (~21 terahertz). Exploiting a scanning and contact-free tungsten tip as a local noise probe, we directly visualize hot-electron distributions before their thermal equilibration with the host gallium arsenide/aluminium gallium arsenide crystal lattice. With nanoconstriction devices, we reveal unexpected nonlocal energy dissipation at room temperature, which is reminiscent of ballistic transport of low-temperature quantum conductors. [ABSTRACT FROM AUTHOR]

To improve fuel efficiency, advanced combustion engines are being designed to minimize the amount of heat wasted in the exhaust. Hence, future generations of catalysts must perform at temperatures that are 100°C lower than current exhaust-treatment catalysts. Achieving low-temperature activity, while surviving the harsh conditions encountered at high engine loads, remains a formidable challenge. In this study, we demonstrate how atomically dispersed ionic platinum (Pt2+) on ceria (CeO2), which is already thermally stable, can be activated via steam treatment (at 750°C) to simultaneously achieve the goals of low-temperature carbon monoxide (CO) oxidation activity while providing outstanding hydrothermal stability. A new type of active site is created on CeO2 in the vicinity of Pt2+, which provides the improved reactivity. These active sites are stable up to 800°C in oxidizing environments. [ABSTRACT FROM AUTHOR]

Operation speed is a key challenge in phase-change random-access memory (PCRAM) technology, especially for achieving subnanosecond high-speed cache memory. Commercialized PCRAM products are limited by the tens of nanoseconds writing speed, originating from the stochastic crystal nucleation during the crystallization of amorphous germanium antimony telluride (Ge2Sb2Te5). Here, we demonstrate an alloying strategy to speed up the crystallization kinetics. The scandium antimony telluride (Sc0.2Sb2Te3) compound that we designed allows a writing speed of only 700 picoseconds without preprogramming in a large conventional PCRAM device. This ultrafast crystallization stems from the reduced stochasticity of nucleation through geometrically matched and robust scandium telluride (ScTe) chemical bonds that stabilize crystal precursors in the amorphous state. Controlling nucleation through alloy design paves the way for the development of cache-type PCRAM technology to boost the working efficiency of computing systems. [ABSTRACT FROM AUTHOR]

The properties of materials change, sometimes catastrophically, as alloying elements and impurities accumulate preferentially at grain boundaries. Studies of bicrystals show that regular atomic patterns often arise as a result of this solute segregation at high-symmetry boundaries, but it is not known whether superstructures exist at general grain boundaries in polycrystals. In bismuth-doped polycrystalline nickel, we found that ordered, segregation-induced grain boundary superstructures occur at randomly selected general grain boundaries, and that these reconstructions are driven by the orientation of the terminating grain surfaces rather than by lattice matching between grains. This discovery shows that adsorbate-induced superstructures are not limited to special grain boundaries but may exist at a variety of general grain boundaries, and hence they can affect the performance of polycrystalline engineering alloys. [ABSTRACT FROM AUTHOR]

This strategy achieved ultrahigh TE performance especially near room temperature, which is extremely rare in TE systems that normally operate in the intermediate temperature range (500 to 800 K). Recently, materials such as Mg-based alloys (5, 6) and silver antimony telluride (AgSbTe2) (7) showed room-temperature TE properties and cooling potential comparable to those of the Bi2Te3-based alloys. INSIGHTS Thermoelectrics is a green-energy technology that can use charge carrier transport within a material to achieve mutual conversion between thermal and electrical energy, consequently enabling both power generation and electronic cooling (1). [Extracted from the article]

A variety of proton (H+)-conducting oxides are known, including those used in electrochemical devices such as fuel cells. In contrast, pure H- conduction, not mixed with electron conduction, has not been demonstrated for oxide-based materials. Considering that hydride ions have an ionic size appropriate for fast transport and also a strong reducing ability suitable for high-energy storage and conversion devices, we prepared a series of K2NiF4-type oxyhydrides, La2-x-ySrx+yLiH1-x+yO3-y, in the hope of observing such H- conductors. The performance of an all-solid-state TiH2/o-La2LiHO3 (x = y = 0, o: orthorhombic)/Ti cell provided conclusive evidence of pure H- conduction. [ABSTRACT FROM AUTHOR]

The article focuses on emergent magnetic monopoles, which are predicted to exist within crystals called spin ices. It cites study which propose that natural constraints in a spin ice restrict monopole motions to a lattice. It states that monopoles could play role in the emerging field of spintronics, an alternative to electronics that uses particles' magnetic fields (spins) rather than their electric charges.

The article focuses on research into the molecular interaction between HIV-1 capsid protein hexamers and the building of mature capsids by capsid proteins. It states that an adaptable hydration layer modulating interactions among capsid proteins is responsible for lattice structure, with disruption of the layer altering hexamer interfaces. It mentions that capsid stability in affected by hydration layer rearrangement, inherent structural plasticity, and effector binding.

Computation of lattice energies to an accuracy sufficient to distinguish polymorphs is a fundamental bottleneck in crystal structure prediction. For the lattice energy of the prototypical benzene crystal, we combined the quantum chemical advances of the last decade to attain sub-kilojoule per mole accuracy, an order-of-magnitude improvement in certainty over prior calculations that necessitates revision of the experimental extrapolation to 0 kelvin. Our computations reveal the nature of binding by improving on previously inaccessible or inaccurate multibody and many-electron contributions and provide revised estimates of the effects of temperature, vibrations, and relaxation. Our demonstration raises prospects for definitive first-principles resolution of competing polymorphs in molecular crystal structure prediction. [ABSTRACT FROM AUTHOR]

Skyrmion crystals are regular arrangements of magnetic whirls that exist in a wide range of chiral magnets. Because of their topology, they cannot be created or destroyed by smooth rearrangements of the direction of the local magnetization. Using magnetic force microscopy, we tracked the destruction of the skyrmion lattice on the surface of a bulk crystal of Fe1-xCoxSi (x = 0.5). Our study revealed that skyrmions vanish by a coalescence, forming elongated structures. Numerical simulations showed that changes of topology are controlled by singular magnetic point defects. They can be viewed as quantized magnetic monopoles and antimonopoles, which provide sources and sinks of one flux quantum of emergent magnetic flux, respectively. [ABSTRACT FROM AUTHOR]

A current limitation in nanoparticle superlattice engineering is that the identities of the particles being assembled often determine the structures that can be synthesized. Therefore, specific crystallographic symmetries or lattice parameters can only be achieved using specific nanopartides as building blocks (and vice versa). We present six design rules that can be used to deliberately prepare nine distinct colloidal crystal structures, with control over lattice parameters on the 25- to 150-nanometer length scale. These design rules outline a strategy to independently adjust each of the relevant crystallographic parameters, including particle size (5 to 60 nanometers), periodicity, and interpartide distance. As such, this work represents an advance in synthesizing tailorable macroscale architectures comprising nanoscale materials in a predictable fashion. [ABSTRACT FROM AUTHOR]

Artificial crystal lattices can be used to tune repulsive Coulomb interactions between electrons. We trapped electrons, confined as a two-dimensional gas in a gallium arsenide quantum well, in a nanofabricated lattice with honeycomb geometry. We probed the excitation spectrum in a magnetic field, identifying collective modes that emerged from the Coulomb interaction in the artificial lattice, as predicted by the Mott-Hubbard model. These observations allow us to determine the Hubbard gap and suggest the existence of a Coulomb-driven ground state. [ABSTRACT FROM AUTHOR]

The recently discovered three-dimensional or bulk topological insulators are expected to exhibit exotic quantum phenomena. It is believed that a trivial insulator can be twisted into a topological state by modulating the spin-orbit interaction or the crystal lattice, driving the system through a topological quantum phase transition. By directly measuring the topological quantum numbers and invariants, we report the observation of a phase transition in a tunable spin-orbit system, BiTL(S1-δSeδ)2, in which the topological state formation is visualized. In the topological state, vortex-like polarization states are observed to exhibit three-dimensional vectorial textures, which collectively feature a chirality transition as the spin momentum-locked electrons on the surface go through the zero carrier density point. Such phase transition and texture inversion can be the physical basis for observing fractional charge (±e/2) and other fractional topological phenomena. [ABSTRACT FROM AUTHOR]

Single crystals are usually faceted solids with homogeneous chemical compositions. Biogenic and synthetic calcite single crystals, however, have been found to incorporate macromolecules, spurring investigations of how large molecules are distributed within the crystals without substantially disrupting the crystalline lattice. Here, electron tomography reveals how random, three-dimensional networks of agarose nanofibers are incorporated into single crystals of synthetic calcite by allowing both high- and low-energy fiber/crystal interface facets to satisfy network curvatures. These results suggest that physical entrapment of polymer aggregates is a viable mechanism by which macromolecules can become incorporated inside inorganic single crystals. As such, this work has implications for understanding the structure and formation of biominerals as well as toward the development of new high-surface area, single-crystal composite materials. [ABSTRACT FROM AUTHOR]

Robust entanglement at room temperature is a necessary requirement for practical applications in quantum technology. We demonstrate the creation of bipartite- and tripartite-entangled quantum states in a small quantum register consisting of individual 13C nuclei in a diamond lattice. Individual nuclear spins are controlled via their hyperuine coupling to a single electron at a nitrogen-vacancy defect center. Quantum correlations are of high quality and persist on a millisecond time scale even at room temperature, which is adequate for sophisticated quantum operations. [ABSTRACT FROM AUTHOR]

Structural information on nanometer-sized gold particles has been limited, due in part to the problem of preparing homogeneous material. Here we report the crystallization and x-ray structure determination of a p-mercaptobenzoic acid (p-MBA)—protected gold nanoparticle, which comprises 102 gold atoms and 44 p-MBAs. The central gold atoms are packed in a Marks decahedron, surrounded by additional layers of gold atoms in unanticipated geometries. The p-MBAs interact not only with the gold but also with one another, forming a rigid surface layer. The particles are chiral, with the two enantiomers alternating in the crystal lattice. The discrete nature of the particle may be explained by the closing of a 58-electron shell. [ABSTRACT FROM AUTHOR]

Under stress, many crystalline materials exhibit irreversible plastic deformation caused by the motion of lattice dislocations. In plastically deformed microcrystals, internal dislocation avalanches lead to jumps in the stress-strain curves (strain bursts), whereas in macroscopic samples plasticity appears as a smooth process. By combining three-dimensional simulations of the dynamics of interacting dislocations with statistical analysis of the corresponding deformation behavior, we determined the distribution of strain changes during dislocation avalanches and established its dependence on microcrystal size. Our results suggest that for sample dimensions on the micrometer and submicrometer scale, large strain fluctuations may make it difficult to control the resulting shape in a plastic-forming process. [ABSTRACT FROM AUTHOR]

A previously unknown rigid helical structure of zinc oxide consisting of a superlattice-structured nanobelt was formed spontaneously in a vapor-solid growth process. Starting from a single-crystal stiff nanoribbon dominated by the c-plane polar surfaces, an abrupt structural transformation into the superlattice-structured nanobelt led to the formation of a uniform nanohelix due to a rigid lattice rotation or twisting. The nanohelix was made of two types of alternating and periodically distributed long crystal stripes, which were oriented with their c axes perpendicular to each other. The nanohelix terminated by transforming into a single-crystal nanobelt dominated by nonpolar (0110) surfaces. The nanohelix could be manipulated, and its elastic properties were measured, which suggests possible uses in electromechanically coupled sensors, transducers, and resonators. [ABSTRACT FROM AUTHOR]

As liquids crystallize into solids on cooling, spins in magnets generally form periodic order. However, three decades ago, it was theoretically proposed that spins on a triangular lattice form a liquidlike disordered state at low temperatures. Whether or not a spin liquid is stabilized by geometrical frustration has remained an active point of inquiry ever since. Our thermodynamic and neutron measurements on NiGa[sub 2]S[sub 4], a rare example of a two-dimensional triangular lattice antiferromagnet, demonstrate that geometrical frustration stabilizes a low-temperature spin-disordered state with coherence beyond the two-spin correlation length. Spin liquid formation may be an origin of such behavior. [ABSTRACT FROM AUTHOR]

Structural materials in nature exhibit remarkable designs with building blocks, often hierarchically arranged from the nanometer to the macroscopic length scales. We report on the structural properties of biosilica observed in the hexactinellid sponge Euplectella sp. Consolidated, nanometer-scaled silica spheres are arranged in well-defined microscopic concentric rings glued together by organic matrix to form laminated spicules. The assembly of these spicules into bundles, effected by the laminated silica-based cement, results in the formation of a macroscopic cylindrical square-lattice cagelike structure reinforced by diagonal ridges. The ensuing design overcomes the brittleness of its constituent material, glass, and shows outstanding mechanical rigidity and stability. The mechanical benefits of each of seven identified hierarchical levels and their comparison with common mechanical engineering strategies are discussed. [ABSTRACT FROM AUTHOR]

Describes the superlattice framework built up of covalently linked Cd17S4(SCH2CH2OH)26 clusters in aqueous solution. X-ray structure determination of the supperlatice structure; Description of the enlarged and interlaced diamond or zinc blende lattices; Structural features; Formation of fractal geometry.

Describes the use of atomic force microscopy to characterize crystal defects and magnetic flux-line lattice in Bi2Sr2CaCu2O8 crystals. Pinning interactions of surface defects; Influence on structure; Implications.

Presents a detailed small-angle neutron scattering study of the vortex lattice in a single crystal of YBa2Cu3O7. Adjustment in orientation for angles 0 to 80 degrees; Implications for the microscopic flux-spinning mechanism.

Helical spin order in magnetic materials has been investigated only in reciprocal space. We visualized the helical spin order and dynamics in a metal silicide in real space by means of Lorentz electron microscopy. The real space of the helical spin order proves to be much richer than that expected from the averaged structure; it exhibits a variety of magnetic defects similar to atomic dislocations in the crystal lattice. The application of magnetic fields allows us to directly observe the deformation processes of the helical spin order accompanied by nucleation, movement, and annihilation of the magnetic defects. [ABSTRACT FROM AUTHOR]

We have observed both superluminal and ultraslow light propagation in an alexandrite crystal at room temperature. Group velocities as slow as 91 meters per second to as fast as -800 meters per second were measured and attributed to the influence of coherent population oscillations involving chromium ions in either mirror or inversion sites within the crystal lattice. Namely, ions in mirror sites are inversely saturable and cause superluminat light propagation, whereas ions in inversion sites experience conventional saturable absorption and produce slow light. This technique for producing large group indices is considerably easier than the existing methods to implement and is therefore suitable for diverse applications. [ABSTRACT FROM AUTHOR]

Examines the high-temperature superconductivity in lattice-expanded C[sub 60]. Expansion of the lattice through intercalation of C[sub 60] with methyl trichloride and methyl tribromide; Increase in the spacing between the C[sub 60] molecules; Modulation of superconducting properties of various materials by application of an electric field.

Presents research which measured zero-point motion and resulting differences in lattice constants in crystals using an x-ray standing wave. Molecular volume of crystals depending on their isotopic masses; Generation of the standing wave; Positions of the surface planes of the film with respect to substrate planes; Results consistent with theoretical predictions.

The article discusses a study on an anomalous porous molecular crystal built of hydrogen cyanide-bonded double-layered components of a segregatively interdigitated architecture consisting of one type of fully aromatic multijoint molecule carrying three identical dipyridylphenyl wedges.

The article discusses research reported elsewhere in the issue by Bakr et al. on quantum phase transformations of individual atoms. The article introduces the research by noting gaps that exist in understanding the physics of quantum-mechanical phases. The noted research team reportedly used a so-called quantum gas microscope to observe and study atoms as they transformed between quantum phases. The experimental process is described with reference to the holographic technique used to create a square crystal lattice.

In the article the author reflects on the ability of materials to control radiation damage. Research suggests that nanomaterials have shown resistance to radiation and exhibit minimal damage when exposed to irradiation. In nanomaterials, grain boundaries send interstitials into the crystal lattice to destroy vacancies.

The article presents information on doping of semiconductors. Doping of semiconductors is usually achieved by incorporating atoms of appropriate elements into the host lattice of the semiconductor. The dopants either release an excess electron as a free negative charge carrier to the semiconductor or they consume one more electron for chemical bonding than they brought with them. Doping can also be achieved by an electron exchange between a semiconductor and dopants situated at its surface. In the field of carbon nanotubes, surface transfer doping is in fact the method of choice for manipulating electronic conductivity.

The article focuses on the collective defect behavior of materials under stress. When materials are subjected to an overload in service conditions they may gently deform plastically rather than breaking abruptly. In the plastic deformation, the total line length of dislocation in a material increases. It has been found that during plastic flow, the interacting dislocation populations tend to spontaneously self-organize into various types of arrangements. In dislocation the average diameter of the crystal decreases in inverse proportion to the applied stress. Dislocations also induce local rotations of the crystal lattice planes. Global differences in lattice orientation between neighboring cells are also induced. The lattice distortions around dislocation cores disturb the X-ray diffraction phenomena used for studying the dislocation. Researchers conducted studies on polycrystals. Observations have revealed about the collective destructions and reconstructions of whole 3D cell structures.

For electrons living on a triangular lattice, the concept of "geometrical frustration" in the face of strong electric mutual repulsion is a crucial, decisive factor that shapes their behavior. In an insulating material, the coulomb repulsion force is relieved if each electron can point its spin anti-parallel to that of its nearest neighbors. On most lattices, this is readily implemented and leads to a state in which spins alternate up and down along each bond direction. On a triangular lattice, however, the geometric arrangement frustrates such ideal regularity.

Focuses on the molecular lattice of diamond. Superimposition of saturated hydrocarbon on the diamond lattice; Description of diamondoid molecule diamantane; Impact of the increase in isomers on the thermodynamics stability of the diamond.

Focuses on the use of ultrafast pulses of x-ray radiation which allows the direct measurement of the changes in crystal lattice structure and loss of crystalline order associated with melting. Monitoring of the light-driven sound waves that give rise to time-dependent changes in unit cell volume; Significance of the development of ultrafast x-ray probes.

Discusses research which first observed a cubic lattice in an infinite solid. Cause of equal spacing in crystalline lattice; Research in this issue by Itano et al from the National Institute of Standards and Technology (NIST), Boulder, Colorado; Previous research; Infinite matter not occurring naturally on Earth; Development and use of ion traps; Spacing between ions; Occurrence of Bragg scattering; Implications of research.

The article discusses research by Ainsley Seago of the Australian National Insect Collection in Canberra, and colleagues, investigating the evolutionary history of iridescence in a group of beetles, called weevils. Topics include the identification three-dimensional (3D) nanostructures in the scales of weevils, called photonic crystals, the crystals' arrangement, and the variation in crystal geometry between species.

The article reports on a study in a 2011 issue of "Nano Letter" regarding materials science research in which scientists, using a liquid-air fabrication method with a low concentration of nanocrystals in the feedstock, created single and binary superlattices.

The article discusses the violation of Wiedemann-Franz law by the crystal lattice. According to the empirical Wiedemann-Franz law the ratio of electronic and thermal conductivity of metals is directly proportional temperature. The theory is one of the oldest relation in condensed matter physics which is supported by quantum mechanics and the Fermi-liquid theory. It was found in the study that this law is followed in one way by crystal lattice while violated in another way. The study discusses how can the behavior of such strongly correlated system be described by modifying the Fermi-liquid theory.

The article reports on a study conducted by researchers to analyze the hexagonally close-packed (hcp) structure of nanoparticles in which two layers stack in an ABAB sequence. It is stated that researchers have detailed why the layers of the hcp structure did not stack in threefold hollow sites and instead form a simple hexagonal lattice structure. Moreover, it also includes the findings of researchers who calculated the total electrostatic and dispersive energies for different lattices that attribute to the stability of the open simple hexagonal packing arrangement of nanoparticles.

The article discusses the quantum hall effect (QHE). The QHE has explained several aspects of quantum physics and engraved the understanding of interacting systems. Efforts were made to extend the QHE temperature range by utilizing semiconductors with small effective masses but all of them were futile. The room temperature of the QHE can be raised or observed with graphene in a single layer of carbon atoms and a honeycomb crystal lattice. The temperature is observed due to unusual nature of charge carriers in graphene.

The article cites a research study focusing on the interaction of porous metal-organic framework (MOF) induced by carbon dioxide (CO2) adsorption lattice. According to the researchers, the interaction of porous MOF materials with adsorbed guest molecules can produce reversible structural transformations. The researchers found that exposure of the MOF to CO2 at 273 K results in an abrupt jump in adsorption. They conducted structural modeling of the material with and without adsorbed CO2. The results indicated that CO2 adsorption and subsequent clathrate formation increases the interlayer distance in the host lattice.

This article presents corrections to various articles published previously in the journal "Science." In the article "Grabbing Hydrogen" published in the November 4 issue, the item should have described the activation of carbon-hydrogen (C-H) bonds as typically proceeding by oxidative addition of a C-H bond to a low-valent metal complex. In another article "Proof of safety at Yucca Mountain," by L.J. Carter and T.H. Pigford, published in the October 21 issue, the figure parts should have been reversed. The URL for the Supporting Online Material was omitted from the article "Bacterial Immunity Traded for Sperm Viability in Male Crickets," by L.W. Simmons and B. Roberts, published in the September 23 issue. In the article "A Chromium Terephthalate-Based Solid With Unusually Large Pore Volumes and Surface Area" by G. Férey, published in the September 23 issue, the crystal structure deposition number for MIL-101 was omitted; the CSD number is 415697.

The article reports on the assumption that molecular diffusion through solid materials proceeds by means of pores that are wide enough to allow passage of molecules. Researchers cast doubt on this assumption by showing that water can diffuse through a seemingly nonporous crystal. They determined the structures of calixarene crystals before and after the crystals had been immersed in water for 8 hours. Calixarenes are macrocyclic compounds that can accommodate small molecules, in this present case, in the cleft of a pincer-like configuration. Despite the absence of discernable channels in the crystals, the post-immersion crystals contain one water per host molecule; the lattice structure is otherwise unchanged. Researchers rule out crystal dissolution and regrowth because the calixarene is not soluble, even in boiling water, and the same crystal was studied before and after immersion. They conclude that concerted movements of calixarenes might allow the water molecules to diffuse through the crystal until they reach a cavity of suitable size.

Crystalline graphite serves as a calibration standard for scanning tunneling microscopy (STM), but the images show only every other atom in the graphite lattice. In contrast, atomic force microscopy (AFM) should be able to image all atoms, yet AFM measurements of attractive forces yield the same incomplete images as STM. Efforts to measure repulsive forces have not been successful because the instrument sensitivity is too low. Scientists show that an AFM with enhanced sensitivity to short-range forces can image all of the carbon atoms on a graphite surface. Their instrument can measure tunneling current and force at the same time and thus serves as both an STM and an AFM. Although the STM image shows only a trigonal lattice, the AFM image reveals the hexagonal carbon rings of the graphite lattice in their entirety.