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Paris Vol. Paris vol. See also, Oeuvres, , Gauthier-Villars, Paris, vol. USA , vol. Rabinowitz, ed. Academic Press, — Google Scholar. Noted in Physics, Springer-Verlag, p. Nauk SSSR, vol. Hulburt, H. American Chemical Society, Washington, D. A Simple Kinetic Model, Eur. Chemie, vol. Die Kinetik der Bromat-Bromidreaktion Monat. Chemie vol. Die Kinetik der Bromatbildung aus Brom Monat.

Chance , 71—79 Google Scholar. Naturforschung A, vol.

The Briggs-Rauscher Reaction

The Kinetic Salt Effect. Chance, et al. Book-B1 81—88 Google Scholar. Nauk SSSR vol. Continue stirring until the potassium iodate is dissolved. Dilute to 1 L. Add Add 4 g of vitex starch. Stir until dissolved. This demonstration evolves iodine. Wear safety goggles and gloves and perform the demonstration in a well-ventilated room, preferably under a ventilation hood.

Use care when preparing the solutions , as the chemicals include strong irritants and oxidizing agents. Neutralize the iodine by reducing it to iodide. Stir until the mixture becomes colorless. The reaction between iodine and thiosulfate is exothermic and the mixture may be hot. Once cool, the neutralized mixture may be washed down the drain with water. This reaction can be broken into two component reactions :.

This reaction can occur by a radical process which is turned on when I - concentration is low, or by a nonradical process when the I - concentration is high. If the R spans the whole space, then the integral gives the total E. These expressions are valid for any excited bound states as well as the ground state. Valence electrons possess their unique.

Runaway chemical reaction exposes community to highly toxic chemicals. The U. Chemical Safety and Hazard Investigation Board CSB conducted a comprehensive investigation of a runaway chemical reaction at MFG Chemical MFG in Dalton, Georgia on April 12, that resulted in the uncontrolled release of a large quantity of highly toxic and flammable allyl alcohol and allyl chloride into the community. Five people were hospitalized and people required decontamination and treatment for exposure to the chemicals.

[] Inheritance of oscillation in chemical reaction networks

This included police officers attempting to evacuate the community and ambulance personnel who responded to calls from residents exposed to the chemicals. This paper presents the findings of the CSB report U. The reactive chemical testing and atmospheric dispersion modeling conducted by CSB after the incident and recommendations adopted by the Board are also discussed. Computer Animation of a Chemical Reaction.

Taking a prototype chemical reaction molecular hydrogen plus hydrogen atom , constructs an accurate semiempirical, generalized diatomics-in-molecules potential energy surface, calculates motions of these atoms on this surface using REACTS trajectory program, and presents results as moving picture on a microcomputer graphics system. Classification of Chemical Reactions : Stages of Expertise. In this study we explore the strategies that undergraduate and graduate chemistry students use when engaged in classification tasks involving symbolic and microscopic particulate representations of different chemical reactions.

We were specifically interested in characterizing the basic features to which students pay attention when classifying…. Aerosol simulation including chemical and nuclear reactions. The numerical simulation of aerosol transport, including the effects of chemical and nuclear reactions presents a challenging dynamic accounting problem. Particles of different sizes agglomerate and settle out due to various mechanisms, such as diffusion, diffusiophoresis, thermophoresis, gravitational settling, turbulent acceleration, and centrifugal acceleration. Particles also change size, due to the condensation and evaporation of materials on the particle.

Heterogeneous chemical reactions occur at the interface between a particle and the suspending medium, or a surface and the gas in the aerosol. Homogeneous chemical reactions occur within the aersol suspending medium, within a particle, and on a surface. Nuclear reactions occur in all locations. These spontaneous transmutations from one element form to another occur at greatly varying rates and may result in phase or chemical changes which complicate the accounting process. This paper presents an approach for inclusion of these effects on the transport of aerosols.

The accounting system is very complex and results in a large set of stiff ordinary differential equations ODEs. The techniques for numerical solution of these ODEs require special attention to achieve their solution in an efficient and affordable manner. Particulate representation of a chemical reaction mechanism. A growing area of interest in chemical education has been the research associated with conceptual understanding at the particulate level.

This study investigated the views of 10 university chemistry lecturers, 85 pre-service chemistry teachers and 23 Secondary 3 equivalent to Year 9 chemistry students about the particulate level of a chemical reaction , namely the heating of copper II carbonate. Four characteristic views were identified on the basis of their diagrammatic representations of particles. These were: a formation of intermediates; b formation of free particles e. Both the majority of the lecturers and the pre-service teachers held an identical view about the reaction mechanism, namely that the decomposition of copper II carbonate goes through a transition stage by forming intermediates.

About one-third of the students had neither any notion of how the atoms in the copper II carbonate lattice interacted and were rearranged in the reaction nor any concept of bond-breaking and reformation in a chemical reaction. Lagrangian descriptors of driven chemical reaction manifolds. The persistence of a transition state structure in systems driven by time-dependent environments allows the application of modern reaction rate theories to solution-phase and nonequilibrium chemical reactions.

However, identifying this structure is problematic in driven systems and has been limited by theories built on series expansion about a saddle point. Recently, it has been shown that to obtain formally exact rates for reactions in thermal environments, a transition state trajectory must be constructed.

Here, using optimized Lagrangian descriptors [G. Craven and R. Hernandez, Phys. In particular, we demonstrate that this is exact for harmonic barriers in one dimension and this verification gives impetus to the application of Lagrangian descriptor-based methods in diverse classes of chemical reactions. The development of these objects is paramount in the theory of reaction dynamics as the transition state structure and its underlying network of manifolds directly dictate reactivity and selectivity.

In a recent paper it was shown that, for chemical reaction networks possessing a subtle structural property called concordance, dynamical behavior of a very circumscribed and largely stable kind is enforced, so long as the kinetics lies within the very broad and natural weakly monotonic class. In particular, multiple equilibria are precluded, as are degenerate positive equilibria. Moreover, under certain circumstances, also related to concordance, all real eigenvalues associated with a positive equilibrium are negative. These conditions are weaker than earlier ones invoked to establish kinetic system injectivity, which, in turn, is just one ramification of network concordance.

Because the Species- Reaction Graph resembles pathway depictions often drawn by biochemists, results here expand the possibility of inferring significant dynamical information directly from standard biochemical reaction diagrams. Chemical reactions in reverse micelle systems. This invention is directed to conducting chemical reactions in reverse micelle or microemulsion systems comprising a substantially discontinuous phase including a polar fluid, typically an aqueous fluid, and a microemulsion promoter, typically a surfactant, for facilitating the formation of reverse micelles in the system.

The system further includes a substantially continuous phase including a non-polar or low-polarity fluid material which is a gas under standard temperature and pressure and has a critical density, and which is generally a water-insoluble fluid in a near critical or supercritical state.

Thus, the microemulsion system is maintained at a pressure and temperature such that the density of the non-polar or low-polarity fluid exceeds the critical density thereof. The method of carrying out chemical reactions generally comprises forming a first reverse micelle system including an aqueous fluid including reverse micelles in a water-insoluble fluid in the supercritical state.

Then, a first reactant is introduced into the first reverse micelle system, and a chemical reaction is carried out with the first reactant to form a reaction product. In general, the first reactant can be incorporated into, and the product formed in, the reverse micelles. A second reactant can also be incorporated in the first reverse micelle system which is capable of reacting with the first reactant to form a product.

Chemical computing with reaction -diffusion processes. Chemical reactions are responsible for information processing in living organisms. It is believed that the basic features of biological computing activity are reflected by a reaction -diffusion medium. We illustrate the ideas of chemical information processing considering the Belousov-Zhabotinsky BZ reaction and its photosensitive variant.

The computational universality of information processing is demonstrated. For different methods of information coding constructions of the simplest signal processing devices are described. The function performed by a particular device is determined by the geometrical structure of oscillatory or of excitable and non-excitable regions of the medium. In a living organism, the brain is created as a self-grown structure of interacting nonlinear elements and reaches its functionality as the result of learning.

We discuss whether such a strategy can be adopted for generation of chemical information processing devices. Recent studies have shown that lipid-covered droplets containing solution of reagents of BZ reaction can be transported by a flowing oil. Therefore, structures of droplets can be spontaneously formed at specific non-equilibrium conditions, for example forced by flows in a microfluidic reactor. We describe how to introduce information to a droplet structure, track the information flow inside it and optimize medium evolution to achieve the maximum reliability.

Applications of droplet structures for classification tasks are discussed. All rights reserved. Minimum Energy Pathways for Chemical Reactions. Computed potential energy surfaces are often required for computation of such parameters as rate constants as a function of temperature, product branching ratios, and other detailed properties. The talk will focus on a number of applications to reactions leading to NOx and soot formation in hydrocarbon combustion. MRI of chemical reactions and processes. As magnetic resonance imaging MRI can spatially resolve a wealth of molecular information available from nuclear magnetic resonance NMR , it is able to non-invasively visualise the composition, properties and reactions of a broad range of spatially-heterogeneous molecular systems.

Hence, MRI is increasingly finding applications in the study of chemical reactions and processes in a diverse range of environments and technologies. This article will explain the basic principles of MRI and how it can be used to visualise chemical composition and molecular properties, providing an overview of the variety of information available. Examples are drawn from the disciplines of chemistry, chemical engineering, environmental science, physics, electrochemistry and materials science.

The review introduces a range of techniques used to produce image contrast, along with the chemical and molecular insight accessible through them. Methods for mapping the distribution of chemical species, using chemical shift imaging or spatially-resolved spectroscopy, are reviewed, as well as methods for visualising physical state, temperature, current density, flow velocities and molecular diffusion.

Strategies for imaging materials with low signal intensity, such as those containing gases or low sensitivity nuclei, using compressed sensing, para-hydrogen or polarisation transfer, are discussed. Systems are presented which encapsulate the diversity of chemical and physical parameters observable by MRI, including one- and two-phase flow in porous media, chemical pattern formation, phase transformations and hydrodynamic fingering instabilities. Lastly, the emerging area of electrochemical MRI is discussed, with studies presented on the visualisation of electrochemical deposition and dissolution processes during corrosion and the operation of batteries, supercapacitors and fuel cells.

Published by Elsevier B. A chemical kinetic theory on muscle contraction and spontaneous oscillation. From a set of chemical kinetic equations describing the actin-activated myosin ATPase cycle, we show that, in active muscle, the fraction of myosin heads in any given biochemical state is independent of both [ADP] and [P i].

Combining muscle mechanics data of Pate and Cooke, we deduce the muscle state equation in which muscle force is a state variable of the muscle system. The theoretical results are consistent with Baker's experimental data but somewhat different from conventional muscle theory. Based on the muscle state equation with the knowledge of special structure of muscle, we present a physical mechanism which can lead to both contraction and oscillation of sarcomeres. It explains the muscle spontaneous oscillatory contraction in a natural way and agrees well with experimental data.

The model will be helpful in studying the oscillatory behavior of cilia and flagella. Chemical reactions directed Peptide self-assembly. Fabrication of self-assembled nanostructures is one of the important aspects in nanoscience and nanotechnology. The study of self-assembled soft materials remains an area of interest due to their potential applications in biomedicine.

The versatile properties of soft materials can be tuned using a bottom up approach of small molecules. Peptide based self-assembly has significant impact in biology because of its unique features such as biocompatibility, straight peptide chain and the presence of different side chain functionality. These unique features explore peptides in various self-assembly process. In this review, we briefly introduce chemical reaction -mediated peptide self-assembly. Herein, we have emphasised enzymes, native chemical ligation and photochemical reactions in the exploration of peptide self-assembly.

Chemical Reactions in Turbulent Mixing Flows. In each I. Flame length fluctuations of Suppression of Ostwald Ripening by Chemical Reactions. Emulsions consisting of droplets immersed in a fluid are typically unstable and coarsen over time. One important coarsening process is Ostwald ripening, which is driven by the surface tension of the droplets.

Ostwald ripening must thus be suppressed to stabilize emulsions, e. Suppression of Ostwald ripening is also important in biological cells, which contain stable liquid-like compartments, e. Such systems are often driven away from equilibrium by chemical reactions and can thus be called active emulsions. Here, we show that non-equilibrium chemical reactions can suppress Ostwald Ripening, leading to stable, monodisperse emulsions. We derive analytical approximations of the typical droplet size, droplet count, and time scale of the dynamics from a coarse-grained description of the droplet dynamics.

We also compare these results to numerical simulations of the continuous concentration fields. Generally, we thus show how chemical reactions can be used to stabilize emulsions and to control their properties in technology and nature. Stochastic flux analysis of chemical reaction networks. Background Chemical reaction networks provide an abstraction scheme for a broad range of models in biology and ecology. The two common means for simulating these networks are the deterministic and the stochastic approaches.

The traditional deterministic approach, based on differential equations, enjoys a rich set of analysis techniques, including a treatment of reaction fluxes. However, the discrete stochastic simulations, which provide advantages in some cases, lack a quantitative treatment of network fluxes. Results We describe a method for flux analysis of chemical reaction networks, where flux is given by the flow of species between reactions in stochastic simulations of the network.

Extending discrete event simulation algorithms, our method constructs several data structures, and thereby reveals a variety of statistics about resource creation and consumption during the simulation. We use these structures to quantify the causal interdependence and relative importance of the reactions at arbitrary time intervals with respect to the network fluxes. This allows us to construct reduced networks that have the same flux-behavior, and compare these networks, also with respect to their time series. We demonstrate our approach on an extended example based on a published ODE model of the same network, that is, Rho GTP-binding proteins, and on other models from biology and ecology.

Conclusions We provide a fully stochastic treatment of flux analysis. As in deterministic analysis, our method delivers the network behavior in terms of species transformations. Moreover, our stochastic analysis can be applied, not only at steady state, but at arbitrary time intervals, and used to identify the flow of specific species between specific reactions.

Our cases study of Rho GTP-binding proteins reveals the role played by the cyclic reverse fluxes in tuning the behavior of this network. Chemical reaction networks provide an abstraction scheme for a broad range of models in biology and ecology. We describe a method for flux analysis of chemical reaction networks, where flux is given by the flow of species between reactions in stochastic simulations of the network.

We provide a fully stochastic treatment of flux analysis. Chimera and phase-cluster states in populations of coupled chemical oscillators. Populations of coupled oscillators may exhibit two coexisting subpopulations, one with synchronized oscillations and the other with unsynchronized oscillations , even though all of the oscillators are coupled to each other in an equivalent manner. This phenomenon, discovered about ten years ago in theoretical studies, was then further characterized and named the chimera state after the Greek mythological creature made up of different animals. The highly counterintuitive coexistence of coherent and incoherent oscillations in populations of identical oscillators , each with an equivalent coupling structure, inspired great interest and a flurry of theoretical activity.

Here we report on experimental studies of chimera states and their relation to other synchronization states in populations of coupled chemical oscillators. Our experiments with coupled Belousov-Zhabotinsky oscillators and corresponding simulations reveal chimera behaviour that differs significantly from the behaviour found in theoretical studies of phase- oscillator models.

Pulse-density modulation control of chemical oscillation far from equilibrium in a droplet open-reactor system. The design, construction and control of artificial self-organized systems modelled on dynamical behaviours of living systems are important issues in biologically inspired engineering. Such systems are usually based on complex reaction dynamics far from equilibrium; therefore, the control of non-equilibrium conditions is required.

We mathematically reveal that the control mechanism is formulated as pulse-density modulation control of the fusion—fission timing. We produce the droplet open-reactor system using microfluidic technologies and then perform external control and autonomous feedback control over autocatalytic chemical oscillation reactions far from equilibrium. We believe that this system will be valuable for the dynamical control over self-organized phenomena far from equilibrium in chemical and biomedical studies.

We mathematically reveal that the control mechanism is formulated as pulse-density modulation control of the fusion-fission timing. Coexistence of wave propagation and oscillation in the photosensitive Belousov-Zhabotinsky reaction on a circular route. The photosensitive Belousov-Zhabotinsky BZ reaction was investigated on a circular ring, which was drawn using computer software and then projected on a film soaked with BZ solution using a liquid-crystal projector.

Under the initial conditions, a chemical wave propagated with a constant velocity on the black ring under a bright background. When the background was rapidly changed to dark, coexistence of the oscillation on part of the ring and propagation of the chemical wave on the other part was observed. These experimental results are discussed in relation to the nature of the photosensitive BZ reaction and theoretically reproduced based on a reaction -diffusion system using the modified Oregonator model. Discusses an experiment designed to introduce students to the basic principles of the fast Fourier transform and Fourier smoothing through transformation of time-dependent optical absorption data from an oscillating reaction.

Uses the Belousov-Zhabotinskii reaction. Describes the experimental setup and data analysis techniques. Scattering Resonances in the Simplest Chemical Reaction. Recent studies of state-resolved angular distributions show the participation of reactive scattering resonances in the simplest chemical reaction. This review is also intended for those who wish to gain insight into the nature of reactive scattering resonances.

Following a tour across several fields of physics and chemistry where the concept of resonance has been crucial for the understanding of new phenomena, we offer an operational definition and taxonomy of reactive scattering resonances. We introduce simple intuitive models to illustrate each resonance type.

Elementary Chemical Reactions in Surface Photocatalysis. Photocatalytic hydrogen evolution and organic degradation on oxide materials have been extensively investigated in the last two decades. Great efforts have been dedicated to the study of photocatalytic reaction mechanisms of a variety of molecules on TiO2 surfaces by using surface science methods under ultra-high vacuum UHV conditions, providing fundamental understanding of surface chemical reactions in photocatalysis.

In this review, we summarize the recent progress in the study of photocatalysis of several important species water, methanol, and aldehydes on different TiO2 surfaces. The results of these studies have provided us deep insights into the elementary processes of surface photocatalysis and stimulated a new frontier of research in this area. Based on the results of these studies, a new dynamics-based photocatalysis model is also discussed. One of the simulation engines of an open-source program called the Molecular Workbench, which can simulate thermodynamics of chemical reactions , is described.

This type of real-time, interactive simulation and visualization of chemical reactions at the atomic scale could help students understand the connections between chemical reaction equations….

Oscillating Reactions

Nonlinear magnetoacoustic wave propagation with chemical reactions. The magnetoacoustic problem with an application to sound wave propagation through electrically conducting fluids such as the ocean in the Earth's magnetic field, liquid metals, or plasmas has been addressed taking into account several simultaneous chemical reactions. Using continuum balance equations for the total mass, linear momentum, energy; as well as Maxwell's electrodynamic equations, a nonlinear beam equation has been developed to generalize the Khokhlov-Zabolotskaya-Kuznetsov KZK equation for a fluid with linear viscosity but nonlinear and diffraction effects.

Thermodynamic parameters are used and not tailored to only an adiabatic fluid case.

The chemical kinetic equations build on a relaxing media approach presented, for example, by K. Naugolnukh and L. Press, Cambridge, ] for a linearized single reaction and thermodynamic pressure equation of state. Approximations for large and small relaxation times and for magnetohydrodynamic parameters [Korsunskii, Sov. Additionally, Cattaneo's equation for heat conduction and its generalization for a memory process rather than a Fourier's law are taken into account. It was introduced for the heat flux depends on the temperature gradient at an earlier time to generate heat pulses of finite speed.

Photoinduced fluorescence intensity oscillation in a reaction -diffusion cell containing a colloidal quantum dot dispersion. The nonlinear spontaneous oscillation of photoluminescence PL intensity in an ensemble of semiconductor quantum dots QDs , which differs from the fluorescence intermittency of a single QD, is investigated.

The PL intensity in a QD dispersion slowly oscillates with time under continuous illumination. The oscillatory behavior is found to vary with changing QD concentration, solvent viscosity, volume fraction of irradiated region, and irradiation intensity. Oscillations occur in a wide variety of cellular processes, for example in calcium and p53 signaling responses, in metabolic pathways or within gene-regulatory networks, e.

Since it is of central importance to understand the influence of perturbations on the dynamics of these systems a number of experimental and theoretical studies have examined their robustness. The period of circadian oscillations has been found to be very robust and to provide reliable timing. For intracellular calcium oscillations the period has been shown to be very sensitive and to allow for frequency-encoded signaling. We here apply a comprehensive computational approach to study the robustness of period and amplitude of oscillatory systems.

We employ different prototype oscillator models and a large number of parameter sets obtained by random sampling. This framework is used to examine the effect of three design principles on the sensitivities towards perturbations of the kinetic parameters. We find that a prototype oscillator with negative feedback has lower period sensitivities than a prototype oscillator relying on positive feedback, but on average higher amplitude sensitivities. For both oscillator types, the use of Michaelis-Menten instead of mass action kinetics in all degradation and conversion reactions leads to an increase in period as well as amplitude sensitivities.

We observe moderate changes in sensitivities if replacing mass conversion reactions by purely regulatory reactions. These insights are validated for a set of established models of various cellular rhythms. Overall, our work highlights the importance of reaction kinetics and feedback type for the variability of period and amplitude and therefore for the establishment of predictive models.

Solving moment hierarchies for chemical reaction networks. Earlier well-known results Feinberg Chem.

Using chemical oscillation to better understand patterns in brain and heart systems

No results exist however for the steady states of non-zero-deficiency networks. In this paper, we show how to write the full moment-hierarchy for any non-zero-deficiency CRN obeying mass-action kinetics, in terms of equations for the factorial moments. Using these, we can recursively predict values for lower moments from higher moments, reversing the procedure usually used to solve moment hierarchies. Chemical factors determine olfactory system beta oscillations in waking rats. Recent studies have pointed to olfactory system beta oscillations of the local field potential Hz and their roles both in learning and as specific responses to predator odors.

To describe odorant physical properties, resultant behavioral responses and changes in the central olfactory system that may induce these oscillations without associative learning, we tested rats with 26 monomolecular odorants spanning 6 log units of theoretical vapor pressure estimate of relative vapor phase concentration and 10 different odor mixtures. We found odorant vapor phase concentration to be inversely correlated with investigation time on the first presentation, after which investigation times were brief and not different across odorants.

Analysis of local field potentials from the olfactory bulb and anterior piriform cortex shows that beta oscillations in waking rats occur specifically in response to the class of volatile organic compounds with vapor pressures of mmHg. Beta oscillations develop over the first three to four presentations and are weakly present for some odorants in anesthetized rats. Gamma oscillations show a smaller effect that is not restricted to the same range of odorants.

Olfactory bulb theta oscillations were also examined as a measure of effective afferent input strength, and the power of these oscillations did not vary systematically with vapor pressure, suggesting that it is not olfactory bulb drive strength that determines the presence of beta oscillations. Theta band coherence analysis shows that coupling strength between the olfactory bulb and piriform cortex increases linearly with vapor phase concentration, which may facilitate beta oscillations above a threshold.

Explodator: A new skeleton mechanism for the halate driven chemical oscillators. In the first part of this work, some shortcomings in the present theories of the Belousov-Zhabotinskii oscillating reaction are discussed. In the second part, a new oscillatory scheme, the limited Explodator, is proposed as an alternative skeleton mechanism.

The new scheme exhibits Hopf bifurcation and limit cycle oscillations. Finally, some possibilities and problems of a generalization are mentioned. Silicon-based sleeve devices for chemical reactions. The reaction chamber combines a critical ratio of silicon and silicon nitride to the volume of material to be heated e. A silicon-based sleeve type chemical reaction chamber is described that combines heaters, such as doped polysilicon for heating, and bulk silicon for convection cooling. Chemical clocks, oscillations , and other temporal effects in analytical chemistry: oddity or viable approach?

Most analytical methods are based on "analogue" inputs from sensors of light, electric potentials, or currents. The signals obtained by such sensors are processed using certain calibration functions to determine concentrations of the target analytes. The signal readouts are normally done after an optimised and fixed time period, during which an assay mixture is incubated. This minireview covers another-and somewhat unusual-analytical strategy, which relies on the measurement of time interval between the occurrences of two distinguishable states in the assay reaction.

These states manifest themselves via abrupt changes in the properties of the assay mixture e. An example of an assay based on time measurement is an oscillating reaction , in which the period of oscillations is linked to the concentration of the target analyte. A number of chemo-chronometric assays, relying on the existing bio transformations or artificially designed reactions , were disclosed in the past few years.

They are very attractive from the fundamental point of view but-so far-only few of them have be validated and used to address real-world problems. Then, can chemo-chronometric assays become a practical tool for chemical analysis? Is there a need for further development of such assays?

We are aiming to answer these questions. This physical chemistry lecture demonstration is designed to aid the understanding of intramolecular energy transfer processes as part of the presentation of the theory of unimolecular reaction rates. Coupled pendulums are used to show the rate of migration of energy between oscillators under resonant and nonresonant conditions with varying…. Plasmon-driven sequential chemical reactions in an aqueous environment. Plasmon-driven sequential chemical reactions were successfully realized in an aqueous environment. In an electrochemical environment, sequential chemical reactions were driven by an applied potential and laser irradiation.

Furthermore, the rate of the chemical reaction was controlled via pH, which provides indirect evidence that the hot electrons generated from plasmon decay play an important role in plasmon-driven chemical reactions. The developed plasmon-driven chemical reactions in an aqueous environment will significantly expand the applications of plasmon chemistry and may provide a promising avenue for green chemistry using plasmon catalysis in aqueous environments under irradiation by sunlight.

While structures and reactivities of many small molecules can be computed efficiently and accurately using quantum chemical methods, heuristic approaches remain essential for modeling complex structures and large-scale chemical systems. Here, we present a heuristics-aided quantum chemical methodology applicable to complex chemical reaction networks such as those arising in cell metabolism and prebiotic chemistry.

Chemical heuristics offer an expedient way of traversing high-dimensional reactive potential energy surfaces and are combined here with quantum chemical structure optimizations, which yield the structures and energies of the reaction intermediates and products. Application of heuristics-aided quantum chemical methodology to the formose reaction reproduces the experimentally observed reaction products, major reaction pathways, and autocatalytic cycles.