scispace - formally typeset
Search or ask a question

Showing papers in "Annual Review of Physical Chemistry in 2008"


Journal ArticleDOI
TL;DR: This review provides a guide to established EOM methods illustrated by examples that demonstrate the types of target states currently accessible by EOM, and touches on some formal aspects of the theory and important current developments.
Abstract: The equation-of-motion coupled-cluster (EOM-CC) approach is a versatile electronic-structure tool that allows one to describe a variety of multiconfigurational wave functions within single-reference formalism. This review provides a guide to established EOM methods illustrated by examples that demonstrate the types of target states currently accessible by EOM. It focuses on applications of EOM-CC to electronically excited and open-shell species. The examples emphasize EOM's advantages for selected situations often perceived as multireference cases [e.g., interacting states of different nature, Jahn-Teller (JT) and pseudo-JT states, dense manifolds of ionized states, diradicals, and triradicals]. I also discuss limitations and caveats and offer practical solutions to some problematic situations. The review also touches on some formal aspects of the theory and important current developments.

856 citations


Journal ArticleDOI
TL;DR: The weak attractions to the confining wall, combined with strong interactions between water molecules, permit exceptionally rapid water flow, exceeding expectations from macroscopic hydrodynamics by several orders of magnitude.
Abstract: Water molecules confined to nonpolar pores and cavities of nanoscopic dimensions exhibit highly unusual properties. Water filling is strongly cooperative, with the possible coexistence of filled and empty states and sensitivity to small perturbations of the pore polarity and solvent conditions. Confined water molecules form tightly hydrogen-bonded wires or clusters. The weak attractions to the confining wall, combined with strong interactions between water molecules, permit exceptionally rapid water flow, exceeding expectations from macroscopic hydrodynamics by several orders of magnitude. The proton mobility along 1D water wires also substantially exceeds that in the bulk. Proteins appear to exploit these unusual properties of confined water in their biological function (e.g., to ensure rapid water flow in aquaporins or to gate proton flow in proton pumps and enzymes). The unusual properties of water in nonpolar confinement are also relevant to the design of novel nanofluidic and molecular separation devices or fuel cells.

656 citations


Journal ArticleDOI
TL;DR: Application of spectrometric methods of pyrometry as well as tools of plasma diagnostics to relative line intensities, profiles, and peak positions have allowed the determination of intracavity temperatures and pressures.
Abstract: Acoustic cavitation, the growth and rapid collapse of bubbles in a liquid irradiated with ultrasound, is a unique source of energy for driving chemical reactions with sound, a process known as sonochemistry. Another consequence of acoustic cavitation is the emission of light [sonoluminescence (SL)]. Spectroscopic analyses of SL from single bubbles as well as a cloud of bubbles have revealed line and band emission, as well as an underlying continuum arising from a plasma. Application of spectrometric methods of pyrometry as well as tools of plasma diagnostics to relative line intensities, profiles, and peak positions have allowed the determination of intracavity temperatures and pressures. These studies have shown that extraordinary conditions (temperatures up to 20,000 K; pressures of several thousand bar; and heating and cooling rates of >10 12 Ks −1 ) are generated within an otherwise cold liquid.

537 citations


Journal ArticleDOI
TL;DR: A general view of the problem regarding soft matter is given and some specific examples of linked simulation techniques at different resolution levels are discussed, including a recently developed flexible simulation scheme, the AdResS method, which allows one to adaptively change the resolution in certain regions of space on demand.
Abstract: The relation between atomistic chemical structure, molecular archi- tecture, molecular weight, and material properties is of basic concern in modern soft material science and includes standard properties of bulk materials and surface and interface aspects, as well as the relation between structure and function in nanoscopic objects and molecular assemblies of both synthetic and biological origin. This all implies a thorough understanding on many length and correspondingly time scales, ranging from (sub)atomistic to macroscopic. Presently, com- puter simulations play an increasingly important, if not central, role. Some problems do not require specific atomistic details, whereas others require them only locally. However, in many cases this strict separation is not sufficient for a comprehensive understanding of systems, and flexible simulation schemes are required that link the different levels of resolution. We here give a general view of the problem regarding soft matter and discuss some specific examples of linked simulation techniques at different resolution levels. We then discuss a recently developed flexible simulation scheme, the AdResS method, which allows one to adaptively change the resolution in certain regions of space on demand.

447 citations


Journal ArticleDOI
Hao Hu1, Weitao Yang1
TL;DR: Progress in QM/MM methodology and applications is reviewed, focusing on ab initio QM-based approaches, with recent developments enabling accurate free-energy determination for reaction processes in solution and in enzymes.
Abstract: Combined quantum mechanics/molecular mechanics (QM/MM) methods provide an accurate and efficient energetic description of complex chemical and biological systems, leading to significant advances in the understanding of chemical reactions in solution and in enzymes. Here we review progress in QM/MM methodology and applications, focusing on ab initio QM-based approaches. Ab initio QM/MM methods capitalize on the accuracy and reliability of the associated quantum-mechanical approaches, however, at a much higher computational cost compared with semiempirical quantum-mechanical approaches. Thus reaction-path and activation free-energy calculations based on ab initio QM/MM methods encounter unique challenges in simulation timescales and phase-space sampling. This review features recent developments overcoming these challenges and enabling accurate free-energy determination for reaction processes in solution and in enzymes, along with applications.

403 citations


Journal ArticleDOI
TL;DR: This work reviews work that addresses connections between globular proteins, percolation clusters, and the similarity of energy flow and thermal transport in these systems and reviews experimental and theoretical studies of the anisotropic flow of energy through the vibrational states of a protein.
Abstract: Energy flows anisotropically through the residues and vibrational states of globular proteins. A variety of experimental and computational studies have identified energy transport channels traversing many residues, in some cases connecting functional regions, potentially important in allostery, and in other cases having no apparent function. This property and the diffusion of energy in proteins are mimicked by transport on a percolation cluster. I review work that addresses connections between globular proteins, percolation clusters, and the similarity of energy flow and thermal transport in these systems. I also review experimental and theoretical studies of the anisotropic flow of energy through the vibrational states of a protein, a property that also can be understood by comparison with simple model disordered systems.

291 citations


Journal ArticleDOI
TL;DR: Attosecond science is coming of age and presently is reaching a level of maturity and sophistication that allows detailed investigations of the role of multielectron dynamics in physics and chemistry.
Abstract: We describe the recent emergence of attosecond science, assessing the present state of the art and discussing several recent examples where attosecond electron dynamics has been studied in atomic and molecular systems. After introducing the generation and characterization of attosecond laser pulses, we describe the use of isolated attosecond pulses in a pump-probe experiment revealing the subcycle time dependence of a multiphoton ionization process and an experiment using the interference from a train of attosecond pulses to extract amplitude and phase information for electronic wave functions. We furthermore discuss experiments where ultrashort laser pulses with a reproducible waveform control electron dynamics in the D2+ molecular ion on attosecond timescales. Attosecond science is coming of age and presently is reaching a level of maturity and sophistication that allows detailed investigations of the role of multielectron dynamics in physics and chemistry.

287 citations


Journal ArticleDOI
TL;DR: A local model of pairing of ions from the solution with charged and polar groups at the protein surface is suggested, in analogy to the air/water interface.
Abstract: The surfaces of aqueous solutions are traditionally viewed as devoid of inorganic ions. Molecular simulations and surface-selective spectroscopic techniques show, however, that large polarizable anions and hydronium cations can be found (and even enhanced) at the surface and are involved in chemistry at the air/water interface. Here, we review recent studies of ions at the air/water interface and compare from this perspective water with other polar solvents. For water, we focus in particular on the surface behavior of its ionic product (i.e., hydronium and hydroxide ions). We also investigate the feasibility of dielectric models for the description of the protein/water interface, in analogy to the air/water interface. Little correlation is found between these two interfaces in terms of ion segregation. Therefore, we suggest a local model of pairing of ions from the solution with charged and polar groups at the protein surface. We also describe corresponding results of experimental studies on aqueous model systems.

266 citations


Journal ArticleDOI
TL;DR: The principles of the X-ray crystallography methodology are reviewed, recent developments in each of the three directions are summarized, and a few examples are illustrated.
Abstract: In 1999, researchers extended X-ray crystallography to allow the imaging of noncrystalline specimens by measuring the X-ray diffraction pattern of a noncrystalline specimen and then directly phasing it using the oversampling method with iterative algorithms. Since then, the field has evolved moving in three important directions. The first is the 3D structural determination of noncrystalline materials, which includes the localization of the defects and strain field inside nanocrystals, and quantitative 3D imaging of disordered materials such as nanoparticles and biomaterials. The second is the 3D imaging of frozen-hydrated whole cells at a resolution of 10 nm or better. A main thrust is to localize specific multiprotein complexes inside cells. The third is the potential of imaging single large protein complexes using extremely intense and ultrashort X-ray pulses. In this article, we review the principles of this methodology, summarize recent developments in each of the three directions, and illustrate a few examples.

250 citations


Journal ArticleDOI
TL;DR: Theoretical work in the past decade has shown that parity-violating potentials in chiral molecules are much larger (typically one to two orders of magnitude) than anticipated on the basis of older theories.
Abstract: We review the high-resolution spectroscopic approach toward the study of intramolecular dynamics, emphasizing molecular parity violation. Theoretical work in the past decade has shown that parity-violating potentials in chiral molecules are much larger (typically one to two orders of magnitude) than anticipated on the basis of older theories. This makes experimental approaches toward small molecular parity-violating effects promising. The concepts and results of intramolecular dynamics derived from spectroscopy are analyzed as a sequence of symmetry breakings. We summarize the concepts of symmetry breakings (de facto and de lege) in view of parity violation in chiral molecules. The experimental schemes and the current status of spectroscopic experiments on molecular parity violation are established. We discuss the promises of detecting and accurately measuring parity-violating energy differences Δpv E on the order of 10−11 J mol−1 (approximately 100 aeV) in enantiomers of chiral molecules with regard to t...

242 citations


Journal ArticleDOI
TL;DR: This review focuses on recent laboratory studies of the heterogeneous and multiphase chemistry and photochemistry of mineral dust aerosol, a large mass fraction of the tropospheric aerosol.
Abstract: It has become increasingly clear that heterogeneous and multiphase chemistry of tropospheric aerosols can change the chemical balance of the atmosphere. In this review, we focus on recent laboratory studies of the heterogeneous and multiphase chemistry and photochemistry of mineral dust aerosol, a large mass fraction of the tropospheric aerosol. Mineral dust aerosol contains a mixture of oxides, clays, and carbonates. Molecular-based studies of reactions of these dust components provide insights into the chemistry of Earth's atmosphere. We discuss several different types of heterogeneous and multiphase reactions, including (a) ozone decomposition, (b) nitrogen dioxide and nitrate photochemistry, and (c) the dissolution and redox chemistry of Fe-containing dust. We also review some of the important chemical concepts that have recently emerged.

Journal ArticleDOI
TL;DR: This work aims to introduce chemists to the pros and cons of first-principles methods that can provide atomic-scale insight into the properties and chemistry of bulk materials, interfaces, and nanostructures.
Abstract: Calculations of the electronic structure of solids began decades ago, but only recently have solid-state quantum techniques become sufficiently reliable that their application is nearly as routine as quantum chemistry is for molecules. We aim to introduce chemists to the pros and cons of first-principles methods that can provide atomic-scale insight into the properties and chemistry of bulk materials, interfaces, and nanostructures. The techniques we review include the ubiquitous density functional theory (DFT), which is often sufficient, especially for metals; extensions such as DFT + U and hybrid DFT, which incorporate exact exchange to rid DFT of its spurious self-interactions (critical for some semiconductors and strongly correlated materials); many-body Green’s function (GW and BetheSalpeter) methods for excited states; quantum Monte Carlo, in principle an exact theory but for which forces (hence structure optimization and dynamics) are problematic; and embedding theories that locally refine the quantum treatment to improve accuracy.

Journal ArticleDOI
TL;DR: In this article, the authors present a continuum elastic theory that captures the onset of the observed folding instability and use digital image analysis to analyze the folding dynamics, and further explore factors that determine the maximum surface pressure a mixed monolayer can sustain and explain the observed phenomenon using the principle of rigidity percolation.
Abstract: When a two-dimensional (2D) film is compressed to its stability limit, it explores the third dimension via collapse. Understanding this 2D-to-3D transition is of great importance as it provides insight into the origin of defects in thin films. This review draws attention to a reversible folding collapse first discovered in model lung surfactant systems and explores the driving forces for this mechanism. The mode of collapse can be tuned by varying the mechanical properties of the film. I present a continuum elastic theory that captures the onset of the observed folding instability and use digital image analysis to analyze the folding dynamics. This article further explores factors that determine the maximum surface pressure a mixed monolayer can sustain and explains the observed phenomenon using the principle of rigidity percolation. The folding transition observed in lipid monolayers described here has also been observed in other systems, including monolayers of nanoparticles.

Journal ArticleDOI
TL;DR: In this article, the recent efforts to investigate the ultrafast structural dynamics of small peptides, such as the unfolding of peptide secondary structure motifs are summarized.
Abstract: We present a detailed discussion of the complimentary fields of the application of two-dimensional infrared (2D-IR) spectroscopy in comparison with two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy. Transient 2D-IR (T2D-IR) spectroscopy of nonequilibrium ensembles is probably one of the most promising strengths of 2D-IR spectroscopy, as the possibilities of 2D-NMR spectroscopy are limited in this regime. T2D-IR spectroscopy uniquely combines ultrafast time resolution with microscopic structural resolution. In this article we summarize our recent efforts to investigate the ultrafast structural dynamics of small peptides, such as the unfolding of peptide secondary structure motifs. The work requires two ingredients: 2D-IR spectroscopy and the possibility of triggering a structural transition of a peptide on an ultrafast timescale using embedded or intrinsic photoswitches. Several photoswitches have been tested, and we discuss our progress in merging these two pathways of research.

Journal ArticleDOI
TL;DR: Meshes present a new opportunity to integrate SPs with experiments and devices-a new instrument in the toolbox of SP techniques that may broaden the range of SP applications.
Abstract: Metal films with patterns of subwavelength holes (grids or meshes) have interesting optical properties including the extraordinary transmission effect. These optically thick metal films transmit more radiation than that incident on the holes owing to the excitation of surface plasmons (SPs). Meshes present a new and simple way to excite SPs at perpendicular incidence (i.e., without the need to vary the angle of the incident beam). This represents a new opportunity to integrate SPs with experiments and devices-a new instrument in the toolbox of SP techniques that may broaden the range of SP applications. This review discusses the discovery, basic optical physics, the role of SPs, and applications of the extraordinary transmission of subwavelength hole arrays.

Journal ArticleDOI
TL;DR: The enabling aspects of nanografting (an atomic force microscopy-based lithography technique) in surface physical chemistry are revealed and one can investigate systematically the influence of ligand local structure on biorecognition and protein immobilization by precisely engineering ligand nanostructures.
Abstract: This article reveals the enabling aspects of nanografting (an atomic force microscopy–based lithography technique) in surface physical chemistry. First, we characterize self-assembled monolayers and multilayers using nanografting to place unknown molecules into a matrix with known structure or vice versa. The availability of an internal standard in situ allows the unknown structures to be imaged and quantified. The same approaches are applied to reveal the orientation and packing of biomolecules (ligands, DNA, and proteins) upon immobilization on surfaces. Second, nanografting enables systematic investigations of size-dependent mechanics at the nanometer scale by producing a series of designed nanostructures and measuring their Young's modulus in situ. Third, one can investigate systematically the influence of ligand local structure on biorecognition and protein immobilization by precisely engineering ligand nanostructures. Finally, we also demonstrate the regulation of the surface reaction mechanism, kin...

Journal ArticleDOI
TL;DR: In this article, the authors review detachment phenomena for prototypical atomic systems, iodide in water and sodide in tetrahydrofuran, and contrast mechanisms as a function of energy from purely charge-transfer-to-solvent detachment to regimes in which there is direct and indirect participation of the bulk conduction band.
Abstract: Photodetachment is a general property of condensed-phase anions exposed to visible or ultraviolet light, but its mechanism has not been fully explored until recently. The combination of femtosecond pump-probe experiments in both bulk liquids and solvated clusters and quantum mechanical descriptions of the relevant excited states has provided new insight into the spectroscopy, energetics, and dynamics of the detachment process. We review detachment phenomena for the prototypical atomic systems, iodide in water and sodide in tetrahydrofuran, and these systems provide the relevant framework for molecular systems. The iodide system has been studied in gas-phase clusters as well as bulk solution. This article also contrasts mechanisms as a function of energy from purely charge-transfer-to-solvent detachment to regimes in which there is direct and indirect participation of the bulk conduction band.

Journal ArticleDOI
TL;DR: This article reviews continuum models for membrane behavior with an emphasis on the use of such models in computational studies and two applications are explored to demonstrate the utility of this level of coarse-grained modeling.
Abstract: The simulation of biological membranes over length and time scales relevant to cellular biology is not currently feasible using conventional (fully atomic or molecularly detailed) simulation strategies. Given the wide disparity between what is possible on today's computers and the problems one might like to study, it seems unlikely this situation will change for several decades. An appealing alternative to traditional computational approaches is to employ simpler, continuum-based models developed within the frameworks of elasticity theory, fluid dynamics, and statistical mechanics. Although such models have seen wide use in analytical descriptions of membrane behavior, the extension of these methods to more general situations and numerical analysis is just beginning to be explored. This article reviews continuum models for membrane behavior with an emphasis on the use of such models in computational studies. Two applications are explored to demonstrate the utility of this level of coarse-grained modeling.

Journal ArticleDOI
TL;DR: This review focuses on the behavior of single-component, water-soluble neutral and charged brushes, and distinguishes between two classes of polymer brushes: those that can be described classically within the context of generalized van der Waals potentials and those thatCan be described by model-dependent potentials arising from specific interactions.
Abstract: This review focuses on the behavior of single-component, water-soluble neutral and charged brushes. Selected examples illustrate how solvation effects, hydrophobic interactions, and electrostatic interactions create complex behaviors not easily captured in mean-field treatments. In particular, we distinguish between two classes of polymer brushes: those that can be described classically within the context of generalized van der Waals potentials and those that can be described by model-dependent potentials arising from specific interactions. In classical systems, only a few global parameters are needed to predict behavior. Nonclassical systems, in contrast, necessitate several local details, which do not necessarily lead to universal scaling laws. Although these nonclassical interactions present unique opportunities for engineering functional surfaces, they also present new challenges for designing well-defined systems with precise control over distributions in the degree of polymerization and tethering density.

Journal ArticleDOI
TL;DR: The structure of hairpins is reviewed including diversity in the stem, loop, and closing base pair, and roles for isolated hairpins, as well as hairpins in the context of complex tertiary structures.
Abstract: Most RNA comprises one strand and therefore can fold back on itself to form complex structures. At the heart of these structures is the hairpin, which is composed of a stem having Watson-Crick base pairing and a loop wherein the backbone changes directionality. First, we review the structure of hairpins including diversity in the stem, loop, and closing base pair. The function of RNA hairpins in biology is discussed next, including roles for isolated hairpins, as well as hairpins in the context of complex tertiary structures. We describe the kinetics and thermodynamics of hairpin folding including models for hairpin folding, folding transition states, and the cooperativity of folding. Lastly, we discuss some ways in which hairpins can influence the folding and function of tertiary structures, both directly and indirectly. RNA hairpins provide a simple means of controlling gene expression that can be understood in the language of physical chemistry.

Journal ArticleDOI
TL;DR: It is demonstrated that bridging the two scales provides the most complete description of the protein universe starting from clearly defined, testable, and physiologically relevant assumptions.
Abstract: Efforts in whole-genome sequencing and structural proteomics start to provide a global view of the protein universe, the set of existing protein structures and sequences. However, approaches based on the selection of individual sequences have not been entirely successful at the quantitative description of the distribution of structures and sequences in the protein universe because evolutionary pressure acts on the entire organism, rather than on a particular molecule. In parallel to this line of study, studies in population genetics and phenomenological molecular evolution established a mathematical framework to describe the changes in genome sequences in populations of organisms over time. Here, we review both microscopic (physics-based) and macroscopic (organism-level) models of protein-sequence evolution and demonstrate that bridging the two scales provides the most complete description of the protein universe starting from clearly defined, testable, and physiologically relevant assumptions.

Journal ArticleDOI
TL;DR: X-ray surface scattering experiments that probe the molecular ordering and phase behavior of surfactants at the water-oil interface are reviewed and the role of chain flexibility and head group interactions on the ordering of long-chain alkanols and alkanoic acids is explored.
Abstract: Surfactants have their primary utility, both scientific and industrial, at the liquid-liquid interface. We review recent X-ray surface scattering experiments that probe the molecular ordering and phase behavior of surfactants at the water-oil interface. The presence of the oil modifies the interfacial ordering in a manner that cannot be understood simply from analogies with studies of Langmuir monolayers of surfactants at the water-vapor interface or from the traditional view that the solvent is fully mixed with the interfacial surfactants. These studies explored the role of chain flexibility and head group interactions on the ordering of long-chain alkanols and alkanoic acids. Small changes in the surfactant may produce large changes in the interfacial ordering. The interfacial monolayer can be spatially homogeneous or inhomogeneous. Investigators have observed interfacial phase transitions as a function of temperature between homogenous phases, as well as between homogeneous and inhomogeneous phases. Finally, varying the solvent chain length can alter the fundamental character of the phase transitions and lead to the formation of multilayer interfacial structures.

Journal ArticleDOI
TL;DR: Solid-state NMR of aligned samples has been used to determine the three-dimensional structures of both the membrane-bound forms of coat proteins in phospholipid bilayers and structural forms in virus particles, which has led to an analysis of the assembly mechanism for virus particles as they are extruded through the cell membrane.
Abstract: Filamentous bacteriophages serve as model systems for the development and implementation of spectroscopic methods suitable for biological supramolecular assemblies. Not only are their coat proteins small and readily prepared in the laboratory, but they also have two primary roles as membrane proteins and as the principal structural element of the virus particles. As a bacterial system, they are readily labeled with stable isotopes, and this has opened possibilities for the many nuclear magnetic resonance (NMR) studies described in this review. In particular, solid-state NMR of aligned samples has been used to determine the three-dimensional structures of both the membrane-bound forms of coat proteins in phospholipid bilayers and structural forms in virus particles, which has led to an analysis of the assembly mechanism for virus particles as they are extruded through the cell membrane.

Journal ArticleDOI
TL;DR: Although carbon chains comprising up to a handful of carbon atoms cannot be the carrier species, which chains remain viable are explored and large oscillator strengths of the odd-numbered carbon chains lie in the 400-900-nm DIB range.
Abstract: Investigators have recorded the electronic spectra of assorted carbon-chain systems in the gas phase using a variety of methods, ranging from direct cavity ringdown absorption spectroscopy to photofragmentation techniques that utilize the cooling capabilities of an ion trap. We summarize the results from these studies and compare them with astronomical measurements of the diffuse interstellar band (DIB) absorptions. Although carbon chains comprising up to a handful of carbon atoms cannot be the carrier species, we explore which chains remain viable. In particular, the (1)Sigma(u)(+)-Chi(1)Sigma(g)(+) transitions of the odd-numbered carbon chains (n = 17,19,...) possess large oscillator strengths and lie in the 400-900-nm DIB range. The origin bands of larger bare carbon rings, such as C(18), have also been observed, with striking similarities to some DIB measurements at high resolution, although at other wavelengths. Finally, we consider recently obtained electronic spectra of metal-containing carbon chains.

Journal ArticleDOI
TL;DR: This article summarizes theoretical studies of molecular state determination by wave-packet interferometry (WPI) and recounts some recent experimental applications of molecular WPI, and describes a new semiclassical theory for condensed-phase WPI and other coherence-spectroscopy measurements.
Abstract: This article summarizes theoretical studies of molecular state determination by wave-packet interferometry (WPI) and recounts some recent experimental applications of molecular WPI. Calculations predict that two-color nonlinear WPI data can be used to reconstruct a rovibronic target wave packet evolving under an incompletely characterized nuclear Hamiltonian. This can be accomplished by the isolation via phase cycling or wave-vector matching of an exhaustive collection of overlaps between the unknown target and the members of a family of reference wave packets whose form is known by construction. This review highlights recent experiments employing WPI to gain amplitude-level information about the photoexcited-state dynamics of small molecules in the gas phase and in rare-gas crystals. I briefly describe a new semiclassical theory for condensed-phase WPI and other coherence-spectroscopy measurements, such as time-resolved coherent anti-Stokes Raman scattering, and mention our initial studies of nonlinear WPI from electronic energy-transfer complexes.

Journal ArticleDOI
TL;DR: A collection of recent efforts that highlight the versatility of short-wavelength ultraviolet light and photogenerated reactive oxygen species as a simple and cost-effective means to pattern a variety of challenging materials and thin-film configurations are reviewed.
Abstract: Patterning physical, chemical, and biological functions at solid surfaces combines technological development with scientific discoveries in many disparate fields. A variety of top-down and bottom-up approaches has proved successful for applications in the solid state, affording large-area patterning at ever-shrinking length scales. Here we review a collection of recent efforts that highlight the versatility of short-wavelength ultraviolet light and photogenerated reactive oxygen species as a simple and cost-effective means to pattern a variety of challenging materials and thin-film configurations. In particular, we discuss two different classes of materials that present different challenges for patterning: fluid phospholipid bilayers at the buried solid-water interface and the surfaces of bulk elastomers. Despite the use of an identical patterning source, the generation and stabilization of patterns in these two classes of materials follow different mechanisms and produce different functionalities.

Journal ArticleDOI
TL;DR: This article contains a very personal account of my evolution as a physical chemist/chemical physicist, with commentary on some of the influences on that evolution and summary accounts of research accomplishments in four of the subject areas that have engaged my attention.
Abstract: This article contains a very personal account of my evolution as a physical chemist/chemical physicist, with commentary on some of the influences on that evolution and summary accounts of research accomplishments in four of the subject areas that have engaged my attention, ranging from isolated molecules to condensed matter.