Complex Chemical Reaction Networks from Heuristics-Aided Quantum Chemistry
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A Chemical Engineering Perspective on the Origins of Life
Processes 2015, 3, 309-338; doi:10.3390/pr3020309 processesOPEN ACCESS ISSN 2227-9717 www.mdpi.com/journal/processes Article A Chemical Engineering Perspective on the Origins of Life Martha A. Grover *, Christine Y. He, Ming-Chien Hsieh and Sheng-Sheng Yu School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Dr. NW, Atlanta, GA 30032, USA; E-Mails: [email protected] (C.Y.H.); [email protected] (M.-C.H.); [email protected] (S.-S.Y.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +1-404-894-2878 or +1-404-894-2866. Academic Editor: Michael Henson Received: 29 January 2015 / Accepted: 19 April 2015 / Published: 5 May 2015 Abstract: Atoms and molecules assemble into materials, with the material structure determining the properties and ultimate function. Human-made materials and systems have achieved great complexity, such as the integrated circuit and the modern airplane. However, they still do not rival the adaptivity and robustness of biological systems. Understanding the reaction and assembly of molecules on the early Earth is a scientific grand challenge, and also can elucidate the design principles underlying biological materials and systems. This research requires understanding of chemical reactions, thermodynamics, fluid mechanics, heat and mass transfer, optimization, and control. Thus, the discipline of chemical engineering can play a central role in advancing the field. In this paper, an overview of research in the origins field is given, with particular emphasis on the origin of biopolymers and the role of chemical engineering phenomena. A case study is presented to highlight the importance of the environment and its coupling to the chemistry. -
Quantum Crystallography†
Chemical Science View Article Online MINIREVIEW View Journal | View Issue Quantum crystallography† Simon Grabowsky,*a Alessandro Genoni*bc and Hans-Beat Burgi*de Cite this: Chem. Sci.,2017,8,4159 ¨ Approximate wavefunctions can be improved by constraining them to reproduce observations derived from diffraction and scattering experiments. Conversely, charge density models, incorporating electron-density distributions, atomic positions and atomic motion, can be improved by supplementing diffraction Received 16th December 2016 experiments with quantum chemically calculated, tailor-made electron densities (form factors). In both Accepted 3rd March 2017 cases quantum chemistry and diffraction/scattering experiments are combined into a single, integrated DOI: 10.1039/c6sc05504d tool. The development of quantum crystallographic research is reviewed. Some results obtained by rsc.li/chemical-science quantum crystallography illustrate the potential and limitations of this field. 1. Introduction today's organic, inorganic and physical chemistry. These tools are usually employed separately. Diffraction and scattering Quantum chemistry methods and crystal structure determina- experiments provide structures at the atomic scale, while the Creative Commons Attribution 3.0 Unported Licence. tion are highly developed research tools, indispensable in techniques of quantum chemistry provide wavefunctions and aUniversitat¨ Bremen, Fachbereich 2 – Biologie/Chemie, Institut fur¨ Anorganische eUniversitat¨ Zurich,¨ Institut fur¨ Chemie, Winterthurerstrasse 190, CH-8057 Zurich,¨ Chemie und Kristallographie, Leobener Str. NW2, 28359 Bremen, Germany. Switzerland E-mail: [email protected] † Dedicated to Prof. Louis J. Massa on the occasion of his 75th birthday and to bCNRS, Laboratoire SRSMC, UMR 7565, Vandoeuvre-l`es-Nancy, F-54506, France Prof. Dylan Jayatilaka on the occasion of his 50th birthday in recognition of their cUniversit´e de Lorraine, Laboratoire SRSMC, UMR 7565, Vandoeuvre-l`es-Nancy, F- pioneering contributions to the eld of X-ray quantum crystallography. -
Quantum Reform
feature Quantum reform Leonie Mueck Quantum computers potentially offer a faster way to calculate chemical properties, but the exact implications of this speed-up have only become clear over the last year. The first quantum computers are likely to enable calculations that cannot be performed classically, which might reform quantum chemistry — but we should not expect a revolution. t had been an exhausting day at the 2012 International Congress of Quantum IChemistry with countless presentations reporting faster and more accurate methods for calculating chemical information using computers. In the dry July heat of Boulder, Colorado, a bunch of young researchers decided to end the day with a cool beer, but the scientific discussion didn’t fade away. Thoughts on the pros and cons of all the methods — the approximations they involved and the chemical problems that they could solve — bounced across the table, until somebody said “Anyway, in a few years we will have a quantum computer and our approximate methods will be obsolete”. An eerie silence followed. What a frustrating thought! They were devoting their careers to quantum chemistry — working LIBRARY PHOTO RICHARD KAIL/SCIENCE tirelessly on applying the laws of quantum mechanics to treat complex chemical of them offering a different trade-off between cannot do on a ‘classical’ computer, it does problems with a computer. And in one fell accuracy and computational feasibility. not look like all the conventional quantum- swoop, would all of those efforts be wasted Enter the universal quantum computer. chemical methods will become obsolete or as chemists turn to quantum computers and This dream machine would basically work that quantum chemists will be out of their their enormous computing power? like a normal digital computer; it would jobs in the foreseeable future. -
Prebiotic Chemistry: Geochemical Context and Reaction Screening
Life 2013, 3, 331-345; doi:10.3390/life3020331 OPEN ACCESS life ISSN 2075-1729 www.mdpi.com/journal/life Article Prebiotic Chemistry: Geochemical Context and Reaction Screening Henderson James Cleaves II Earth Life Science Institute, Tokyo Institute of Technology, Institute for Advanced Study, Princeton, NJ 08540, USA; E-Mail: [email protected] Received: 12 April 2013; in revised form: 17 April 2013 / Accepted: 18 April 2013 / Published: 29 April 2013 Abstract: The origin of life on Earth is widely believed to have required the reactions of organic compounds and their self- and/or environmental organization. What those compounds were remains open to debate, as do the environment in and process or processes by which they became organized. Prebiotic chemistry is the systematic organized study of these phenomena. It is difficult to study poorly defined phenomena, and research has focused on producing compounds and structures familiar to contemporary biochemistry, which may or may not have been crucial for the origin of life. Given our ignorance, it may be instructive to explore the extreme regions of known and future investigations of prebiotic chemistry, where reactions fail, that will relate them to or exclude them from plausible environments where they could occur. Come critical parameters which most deserve investigation are discussed. Keywords: chemical evolution; prebiotic organic reactions-prebiotic reactions in the aqueous phase; prebiotic reactions in the solid state; energy sources on the primitive Earth; mineral catalysis 1. Introduction Prebiotic chemistry is the study of how organic compounds formed and self-organized for the origin of life on Earth and elsewhere [1]. -
Formose Reaction Controlled by a Copolymer of N,N-Dimethylacrylamide and 4-Vinylphenylboronic Acid
polymers Article Formose Reaction Controlled by a Copolymer of N,N-Dimethylacrylamide and 4-Vinylphenylboronic Acid Tomohiro Michitaka, Toru Imai and Akihito Hashidzume * ID Department of Macromolecular Science, Graduate School of Science, Osaka University, Osaka 560-0043, Japan; [email protected] (T.M.); [email protected] (T.I.) * Correspondence: [email protected]; Tel.: +81-6-6850-8174 Received: 8 October 2017; Accepted: 24 October 2017; Published: 25 October 2017 Abstract: The formose reaction is an oligomerization of formaldehyde under basic conditions, which produces a complicated mixture of monosaccharides and sugar alcohols. Selective formation of useful monosaccharides by the formose reaction has been an important challenge. In this study, we have investigated the formose reaction controlled by N,N-dimethylacrylamide/4-vinylphenylboronic acid copolymer (pDMA/VBA) and phenylboronic acid (PBA) because boronic acid compounds form esters with polyols, e.g., monosaccharides and sugar alcohols. We obtained time–conversion data in the presence of these boronic acid compounds, and characterized the products by liquid chromatography-mass spectroscopy and NMR measurements. pDMA/VBA and PBA decelerated the formose reaction because of the formation of boronic acid esters with products. It is noteworthy that the formose reaction in the presence of pDMA/VBA and PBA formed favorably six- and seven-carbon branched monosaccharides and sugar alcohols. Keywords: formose reaction; boronic acid compounds; N,N-dimethylacrylamide/4-vinylphenyl boronic acid copolymer; phenylboronic acid; monosaccharides; sugar alcohols 1. Introduction Carbohydrates are ubiquitous in our life and very important biological materials [1,2]. Carbohydrates can be divided into three categories based on their molecular weight; (1) low molecular weight saccharides, e.g., monosaccharides and disaccharides, (2) oligosaccharides, and (3) polysaccharides. -
Inferring Chemical Reaction Patterns Using Rule Composition in Graph Grammars Jakob L Andersen1,4, Christoph Flamm2*, Daniel Merkle1* and Peter F Stadler2,3,4,5,6,7
Andersen et al. Journal of Systems Chemistry 2013, 4:4 http://www.jsystchem.com/content/4/1/4 RESEARCH ARTICLE Open Access Inferring chemical reaction patterns using rule composition in graph grammars Jakob L Andersen1,4, Christoph Flamm2*, Daniel Merkle1* and Peter F Stadler2,3,4,5,6,7 Abstract Background: Modeling molecules as undirected graphs and chemical reactions as graph rewriting operations is a natural and convenient approach to modeling chemistry. Graph grammar rules are most naturally employed to model elementary reactions like merging, splitting, and isomerisation of molecules. It is often convenient, in particular in the analysis of larger systems, to summarize several subsequent reactions into a single composite chemical reaction. Results: We introduce a generic approach for composing graph grammar rules to define a chemically useful rule compositions. We iteratively apply these rule compositions to elementary transformations in order to automatically infer complex transformation patterns. As an application we automatically derive the overall reaction pattern of the Formose cycle, namely two carbonyl groups that can react with a bound glycolaldehyde to a second glycolaldehyde. Rule composition also can be used to study polymerization reactions as well as more complicated iterative reaction schemes. Terpenes and the polyketides, for instance, form two naturally occurring classes of compounds of utmost pharmaceutical interest that can be understood as “generalized polymers” consisting of five-carbon (isoprene) and two-carbon units, respectively. Conclusion: The framework of graph transformations provides a valuable set of tools to generate and investigate large networks of chemical networks. Within this formalism, rule composition is a canonical technique to obtain coarse-grained representations that reflect, in a natural way, “effective” reactions that are obtained by lumping together specific combinations of elementary reactions. -
Quantum Chemistry and Spectroscopy – Spring 2018
CHE 336 – Quantum Chemistry and Spectroscopy – Spring 2018 Instructor: Dr. Jessica Sarver Email: [email protected] Office: HSC 364 (email hours: 8 am – 10 pm) Office Hours: 10am-12pm Tuesday, 2-3pm Wednesday, 10:30-11:30am Friday, or by appointment Course Description (from Westminster undergraduate catalog) Quantum chemistry and spectroscopy is the study of the microscopic behavior of matter and its interaction with electromagnetic radiation. Topics include the formulation and application of quantum mechanical models, atomic and molecular structure, and various spectroscopic techniques. Laboratory activities demonstrate the fundamental principles of physical chemistry. Methods that will be used during the laboratory portion include: polarimetry, UV-Vis and fluorescence spectroscopies, electrochemistry, and computational/molecular modeling. Prerequisites: C- grade in CHE 117 and MTH 152 and PHY 152. Course Outcomes The chemistry major outcomes are: • Describe and explain quantum theory and the three quantum mechanical models of motion. • Describe and explain how these theories/models are applied and incorporated to applications of atomic/molecular structure and spectroscopy. • Describe and explain the principles of four major types of spectroscopy and their applications. • Describe and explain the measurable thermodynamic parameters for physical and chemical processes and equilibria. • Describe and explain how chemical kinetics can be used to investigate time-dependent processes. • Solve mathematical problems based on physical chemical principles and connect the numerical results with these principles. Textbook The text for this course is Physical Chemistry, 10th Ed. by Atkins and de Paula. Readings and problem set questions will be assigned from this text. You are strongly urged to get a copy of this textbook and complete all the assigned readings and homework. -
The Power of Crowding for the Origins of Life
Orig Life Evol Biosph (2014) 44:307–311 DOI 10.1007/s11084-014-9382-5 ORIGIN OF LIFE The Power of Crowding for the Origins of Life Helen Greenwood Hansma Received: 2 October 2014 /Accepted: 2 October 2014 / Published online: 14 January 2015 # Springer Science+Business Media Dordrecht 2015 Abstract Molecular crowding increases the likelihood that life as we know it would emerge. In confined spaces, diffusion distances are shorter, and chemical reactions produce fewer and more regular products. Crowding will occur in the spaces between Muscovite mica sheets, which has many advantages as a site for life’s origins. Keywords Muscovite mica . Molecular crowding . Origin of life . Mechanochemistry. Abiogenesis . Chemical confinement effects . Chirality. Protocells Cells are crowded. Protein molecules in cells are typically so close to each other that there is room for only one protein molecule between them (Phillips, Kondev et al. 2008). This is nothing like a dilute ‘prebiotic soup.’ Therefore, by analogy with living cells, the origins of life were probably also crowded. Molecular Confinement Effects Many chemical reactions are limited by the time needed for reactants to diffuse to each other. Shorter distances speed up these reactions. Molecular complementarity is another principle of life in which pairs or groups of molecules form specific interactions (Root-Bernstein 2012). Current examples are: enzymes & substrates & cofactors; nucleic acid base pairs; antigens & antibodies; nucleic acid - protein interactions. Molecular complementarity is likely to have been involved at life’s origins and also benefits from crowding. Mineral surfaces are a likely place for life’s origins and for formation of polymeric molecules (Orgel 1998). -
Introduction to Quantum Chemistry
Chem. 140B Dr. J.A. Mack Introduction to Quantum Chemistry Why as a chemist, do you need to learn this material? 140B Dr. Mack 1 Without Quantum Mechanics, how would you explain: • Periodic trends in properties of the elements • Structure of compounds e.g. Tetrahedral carbon in ethane, planar ethylene, etc. • Bond lengths/strengths • Discrete spectral lines (IR, NMR, Atomic Absorption, etc.) • Electron Microscopy & surface science Without Quantum Mechanics, chemistry would be a purely empirical science. (We would be no better than biologists…) 140B Dr. Mack 2 1 Classical Physics On the basis of experiments, in particular those performed by Galileo, Newton came up with his laws of motion: 1. A body moves with a constant velocity (possibly zero) unless it is acted upon by a force. 2. The “rate of change of motion”, i.e. the rate of change of momentum, is proportional to the impressed force and occurs in the direction of the applied force. 3. To every action there is an equal and opposite reaction. 4. The gravitational force of attraction between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them. m m F = G × 1 2 r 2 140B Dr. Mack 3 The Failures of Classical Mechanics 1. Black Body Radiation: The Ultraviolet Catastrophe 2. The Photoelectric Effect: Einstein's belt buckle 3. The de Broglie relationship: Dude you have a wavelength! 4. The double-slit experiment: More wave/particle duality 5. Atomic Line Spectra: The 1st observation of quantum levels 140B Dr. Mack 4 2 Black Body Radiation Light Waves: Electromagnetic Radiation Light is composed of two perpendicular oscillating vectors waves: A magnetic field & an electric field As the light wave passes through a substance, the oscillating fields can stimulate the movement of electrons in a substance. -
4 Carbohydrates
Basic classes of biomolecules • Aminoacids • Lipids • Carbohydrates (sugars) • Nucleobases • Nucleosides (sugar+nucleobase) Nucleotides - components Phosphates and the prebiotic synthesis of oligonucleotides Activated ribonucleotides in the potentially prebiotic assembly of RNA. Potential P–O bond forming polymerization chemistry is indicated by the curved arrows. Phosphorylation reagents DAP M. A. Pasek, et al. Angew. Chem. Int. Ed. 2008, 47, 7918-7920 A. Eschenmoser, et al. Orig. Life Evol. Biosph. 1999, 29, 333-354 Phosphorylation reagents DAP M. A. Pasek, et al. Angew. Chem. Int. Ed. 2008, 47, 7918-7920 A. Eschenmoser, et al. Orig. Life Evol. Biosph. 1999, 29, 333-354 Phosphorylation of sugars A. Eschenmoser, et al. Angew. Chem. Int. Ed. 2000, 39, 2281-2285 Phosphorylation of sugars A. Eschenmoser, et al. Angew. Chem. Int. Ed. 2000, 39, 2281-2285 Nucleosides - nucleobases + sugars Carbohydrates Formose reaction Alexander Butlerov (1828-1886) St. Petersburg, Kazan, Russia The reaction begins with two formaldehyde molecules condensing to make glycolaldehyde 1 which further reacts in an aldol reaction with another equivalent of formaldehyde to make glyceraldehyde 2. An aldose-ketose isomerization of 2 forms dihydroxyacetone 3 which can Ronald Breslow (1931-) react with 1 to form ribulose 4, and through another isomerization ribose 5. Molecule 3 also Columbia University, USA can react with formaldehyde to produce tetrulose 6 and then aldoltetrose 7. Molecule 7 can split into 2 in a retro-aldol reaction. Formaldehyde condensation Aldol -
Computational Analysis of the Mechanism of Chemical Reactions
Computational Analysis of the Mechanism of Chemical Reactions in Terms of Reaction Phases: Hidden Intermediates and Hidden Transition States ELFI KRAKA* AND DIETER CREMER Department of Chemistry, Southern Methodist University, 3215 Daniel Avenue, Dallas, Texas 75275-0314 RECEIVED ON JANUARY 9, 2009 CON SPECTUS omputational approaches to understanding chemical reac- Ction mechanisms generally begin by establishing the rel- ative energies of the starting materials, transition state, and products, that is, the stationary points on the potential energy surface of the reaction complex. Examining the intervening spe- cies via the intrinsic reaction coordinate (IRC) offers further insight into the fate of the reactants by delineating, step-by- step, the energetics involved along the reaction path between the stationary states. For a detailed analysis of the mechanism and dynamics of a chemical reaction, the reaction path Hamiltonian (RPH) and the united reaction valley approach (URVA) are an effi- cient combination. The chemical conversion of the reaction complex is reflected by the changes in the reaction path direction t(s) and reaction path curvature k(s), both expressed as a function of the path length s. This information can be used to partition the reaction path, and by this the reaction mech- anism, of a chemical reaction into reaction phases describing chemically relevant changes of the reaction complex: (i) a contact phase characterized by van der Waals interactions, (ii) a preparation phase, in which the reactants prepare for the chemical processes, (iii) one or more transition state phases, in which the chemical processes of bond cleavage and bond formation take place, (iv) a product adjustment phase, and (v) a separation phase. -
Six Phases of Cosmic Chemistry
Six Phases of Cosmic Chemistry Lukasz Lamza The Pontifical University of John Paul II Department of Philosophy, Chair of Philosophy of Nature Kanonicza 9, Rm. 203 31-002 Kraków, Poland e-mail: [email protected] 1. Introduction The steady development of astrophysical and cosmological sciences has led to a growing appreciation of the continuity of cosmic history throughout which all known phenomena come to being. This also includes chemical phenomena and there are numerous theoretical attempts to rewrite chemistry as a “historical” science (Haken 1978; Earley 2004). It seems therefore vital to organize the immense volume of chemical data – from astrophysical nuclear chemistry to biochemistry of living cells – in a consistent and quantitative fashion, one that would help to appreciate the unfolding of chemical phenomena throughout cosmic time. Although numerous specialist reviews exist (e.g. Shaw 2006; Herbst 2001; Hazen et al. 2008) that illustrate the growing appreciation for cosmic chemical history, several issues still need to be solved. First of all, such works discuss only a given subset of cosmic chemistry (astrochemistry, chemistry of life etc.) using the usual tools and languages of these particular disciplines which does not facilitate drawing large-scale conclusions. Second, they discuss the history of chemical structures and not chemical processes – which implicitly leaves out half of the totality chemical phenomena as non-historical. While it may now seem obvious that certain chemical structures such as aromatic hydrocarbons or pyrazines have a certain cosmic “history”, it might cause more controversy to argue that chemical processes such as catalysis or polymerization also have their “histories”.