Abstracts of the CTTC 2016
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Contributor's name
Affiliation
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Speakers
Mercedes Alonso
Vrije Univ., Belgium
Expanded Porphyrins: from Understanding to Rational Design
In this talk, the use of computational chemistry to reveal the critical factors controlling the structure and properties of expanded porphyrins in different environments is presented. Through extensive density functional theory calculations, we recently demonstrated that the molecular topology is highly influenced by the number of π-electrons and the size of the macrocycle.[1] Aromaticity emerged as the key concept determining the electronic, transport and nonlinear optical properties of expanded porphyrins and accordingly, we proposed different methods to quantify the Hückel and the Möbius aromaticity. By using these descriptors, the structure-property relationships between the molecular topology, aromaticity and nonlinear optical properties was established and the optimum conditions for viable Möbius systems and optical switches were determined.[4]
Finally, I will show how quantum-chemical methods can be used for understanding and predicting the metalation effect in expanded porphyrins. Using energy decomposition analysis, we have recently found that the molecular topology of d8 metal complexes of hexaphyrins depends on the sensitive interplay between the intrinsic ligand strain and the metal-ligand interaction strain. As such, aromaticity of the ligand and effective charge of the metal are revealed as key factors determining the binding mode and the preference for Möbius or Hückel structures. These findings offer a new perspective to rationalize the experimental observations and we proposed several guidelines for designing novel complexes of hexaphyrins.[5]
[1] Alonso, M.; Geerlings, P.; De Proft, F. Chem. Eur. J. 2012, 18, 10916; Chem. Eur. J. 2013, 19, 1617; J. Org. Chem. 78, 4419 (2013). [2] a) Alonso, M.; Geerlings, P.; De Proft, F. Phys. Chem. Chem. Phys. 2014, 16, 14396; b) Woller, T.; Contreras-García; J.; Geerlings, P.; De Proft, F.; Alonso, M. Phys. Chem. Chem. Phys. 2016, 18, 11885.[3] Alonso, M.; Balazs, P.; Geerlings, P.; De Proft, F. Chem. Eur. J. 2015, 21, 17631.
Ramiro Arratia-Perez
Universidad Andrés Bello, Chile
Molecular Sensors for Diagnostic
We have synthesized Re organometallic complexes and further characterized by X-ray diffraction, NMR, IR, UV, electrochemistry and relativistic DFT calculations. We explored their intracellular localization by taking advantage of its revealed luminescence. We have developed several biological applications in the fields of precision agriculture and public health issues. In particular, we have designed molecular sensors for the detection of Botrytis cinerea, and we have synthesized a molecular compound that inhibits the growth of this fungus that attack grapes, pepper, tomatoes, cannabis, etc. This finding have the potential for establishing a protocol in precision agriculture. We also assessed the antimicrobial and bactericide activities of some of our organometallic complexes in bacteria (Salmonella enterica) and yeast (Cryptococcus spp., Candida albicans and Candida tropicalis)that affect human beings. We observed that our complexes exerts antifungal effects against Crytococcus spp. and has proven to be suitable markers for bacteria and yeast sensing. We determined their minimal inhibitory concentration (MIC).
[1] A. Carreno, R. Arratia-Perez et al. New J. Chem. 2015, 39, 7822-7831.
[2] A. Carreno, R. Arratia-Perez et al. New J. Chem. 2016, 40, 2362-2375.
[3] A. Carreno, R. Arratia-Perez et al. New J. Chem. 2015, 39, 5725-5734.
Acknowledgement. We thank Millennium Nucleus 120001 for financial support.
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Paul Ayers
McMaster Univ., Canada
Strong Electron Correlation
Since the electronic Schrödinger equation is too complicated to be soluble for most interesting chemical systems, the task of the quantum chemist is to develop practical approximations that provide accurate models for the behavior of electrons in molecules. The difficulty of the underlying problem implies that these models are necessarily limited to certain special cases. For example, it is relatively easy to describe cases where the electrons in a molecule move nearly independently, so that the motion of one electron does not affect others very much. When this is not true, many of our conceptual precepts lose their utility (e.g., the notion of an electron configuration, and even the mere concept of orbitals) and many popular computational quantum chemistry methods become unreliable. In this lecture, I will discuss quantum chemical models for strongly correlated molecules, focusing on alternatives to orbital-based models.
Roi Baer
The Hebrew Univ. Jerusalem
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Evert J. Baerends
VU University Amsterdam
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Kati Finzel
Linköping Univ., Sweden
Recent advances in orbital-free density functional theory
Orbital-free density functional theory (OF-DFT) promises a reliable physical description at relatively low computational cost [1,2]. However, progress was hampered due to an insufficient knowledge how to model the Pauli exclusion principle within an orbital-free approach, consequently leading to structureless bosonic-like electron densities. Recently, the mathematic connection between the atomic shell structure in real space and the Pauli exclusion principle has been established for any set of (1s,2s)-orbitals [3]. Reversely, imposing local conditions on the Pauli potential [4] for a proper representation of the atomic shell structure assures properly structured electron densities from variational orbital-free calculations [4,5]. The method is applicable to all atoms in the Periodic Table [6] and extendable to bound Coulomb systems [7].
[1] P. Hohenberg, W. Kohn, Phys. Rev. B 1964, 136, 864. [2] M Levy, J. P. Perdew, V. Sahni, Phys. Rev. A 1984, 30, 2745. [3] K. Finzel, Theor. Chem. Acc. 2016, 135, 148. [4] K. Finzel, J. Chem. Phys. 2016, 144, 034108. [5] K. Finzel, Int. J. Quantum Chem. 2015, 115, 1629. [6] K. Finzel, Theor. Chem. Acc. 2016, 135, 87. [7] K. Finzel, Int. J. Quantum Chem. 2016, doi: 10.1002/qua.25169.
José Luis Gázquez
UAM-Iztapalapa, Mexico
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Peter Gill
Austr. Nat. Univ., Australia
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Ireneusz Grabowski
Nicolaus Copernicus University
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Yuri Grin
Dresden Max Plank, Germany
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Miquel Huix-Rotllant
Université Aix-Marseille, France
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Xiaosong Li
Univ. Washignton US
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Eduardo V. Ludeña
CIDNA-ESPOL, Guayaquil, Ecuador
Approximate Kinetic Energy Functionals Expressed as a Power Series of the One-Electron Density
Eduardo V. Ludeña, 1,2 Edison X. Salazar.3 Pedro Guarderas, 4 Mauricio H. Cornejo, 1 Valentin V. Karasiev, 5 Dario Arroyo. 6
1 Center of Nanotechnology Research and Development (CIDNA), ESPOL, Km 30.5 Vía Perimetral, Campus Gustavo Galindo, Guayaquil, Ecuador; 2 Centro de Química, Instituto Venezolano de Investigaciones Científicas, IVIC, Apartado 21827, Caracas, Venezuela; 3 Universidad Regional Amazónica IKIAM, Km 7 Vía Muyuna, Tena, Ecuador; 4 Universidad Central del Ecuador, Cdla. Universitaria, Quito, Ecuador; 5 Quantum Theory Project, Departments of Physics and Chemistry, P.O. Box 118435, University of Florida, Gainesville, Florida, 32611-8435, US; 6 Departamento de Física, Escuela Politécnica Nacional, Quito, Ecuador
Summary
Based on the Liu-Parr expansion (Liu and Parr, Phys Rev A 1997, 55, 1792) for the functional of the non-interacting kinetic energy, given in terms of a power series of the one-electron density, we investigate the adequateness of this approximation to describe the behavior of the kinetic energy enhancement factor for atoms from Li to Kr. It is shown that that the three-term Liu-Parr expansion when corrected locally by a term containing the Laplacian of the density - which does not modify the kinetic energy values – provides enhancement factors which approach quite closely the exact ones.[1]
In addition we apply these series to represent the Pauli kinetic energy functional and explore the effect that the size of the expansion has on the accuracy of the approximation. In particular, we examine the effect that a shell-by-shell mean-square optimization of the expansion coefficients has on the kinetic energy values. The results yield a mean absolute percentage error of 0.07, 0.04, 0.03 and 0.01 for expansions with 4, 5, 6 and 7 optimized coefficients,respectively.[2] These results are the most accurate ones as yet obtained for the representation of the non-interacting kinetic energy functional.
[1]. Edison X. Salazar,* Pedro F. Guarderas, Eduardo V. Ludeña, Mauricio H. Cornejo, Valentin V. Karasiev, Study of Some Simple Approximations to the Non-Interacting Kinetic Energy Functional, International Journal of Quantum Chemistry 2016, DOI: 10.1002/qua.25179.
[2]. Eduardo V. Ludeña, Edison X. Salazar, Mauricio H. Cornejo, Darío Arroyo, Pedro Guarderas. Representation of the Pauli kinetic energy functional in terms of the Liu-Parr power series expansion: Application to atoms. (To be submitted to The Physical Review A).
Ángel Martín Pendás
Universidad de Oviedo. Spain
Towards real space indicators of the metallic state: Partitioning the localization (or position spread) tensor.
The search for real space indicators of metallic behavior is an active field that has been lately revitalized after recognizing that the algebraic or exponential decay rate of delocalization indices may be used to differentiate conductors from insulators [1,2]. Here we analyze the Localization Tensor introduced by Kohn [3], further developed by Resta [4], and recently applied in the molecular realm by Evangelisti [5]. We show how to partition it in an origin independent manner, and relate it to previous work.
[1] A. Gallo-Bueno, A. Martín Pendás, Phys. Chem. Chem. Phys. 2016 18, 11772. [2] A. Gallo-Bueno, M. Kohout, A. Martín Pendás, submitted. [3] W. Kohn, Phys. Rev. 1964, 133, A171. [4] R. Resta, Phys. Rev. Lett. 1998, 80, 1800. [5] O. Brea et. al., J. Chem. Theory Comput. 2013, 9, 6286.
Gabriel Merino
Centro de Investigacion y de Estudios Avanzados, Mexico
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Vladimiro Mujica
Univ. Arizona, US and Donostia Int. Physics Center (DIPC)
Theoretical modeling of solar cells and photovoltaic devices
The description, control and understanding of a complex system that performs the conversion of light into a voltage generation is a complex problem that involves the use of different tools ranging from pure quantum mechanics to the theory of open systems. In this talk, I will review some of the most important ingredients of such a theoretical description including the key issues of interfacial charge and energy transport, time and length scales, the competition between charge separation and charge recombination and the most important requirements and limitations for real systems. Finally, I will examine the most relevant architectures and designs for these devices.
Sílvia Osuna
Univ. Girona, Spain
Active Site Dynamics in Designed and Laboratory-generated Enzymes
In this talk, the use of molecular dynamics (MD) simulations to reveal how mutations alter the structure and organization of enzyme active sites is presented.[1] As initially proposed by Pauling, and elaborated by many others since then, biocatalysis is efficient when the catalytic residues in the active site of an enzyme are in optimal positions for transition state stabilization. Using MD simulations, we explore the dynamical pre-organization of the active sites of designed and evolved enzymes, by analyzing the fluctuations between active and inactive conformations normally concealed to static crystallography. MD shows how the various arrangements of active site residues influence the free energy of the transition state, and relates the populations of the catalytic conformational ensemble to enzyme activity.
[1] Osuna, S; Jiménez-Osés, G.; Noey, L.; Houk, K. N. Molecular Dynamics Explorations of Active Site Structure in Designed and Evolved Enzymes, Acc. Chem. Res. 2015, 48, 1080-1089.
Kasia Pernal
Tech. Univ. Lodz, Poland
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Lucia Reining
ETSF, France
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Albeiro Restrepo
Univ. Antioquia, Colombia
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Tomas Rocha
Univ. Autónoma de México, México
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Jorge Seminario
Texas A&M University, US
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Alejandro Toro-Labbe
Pont. Univ. Cat. Chile, Chile
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Sam Trickey
University of Florida, US
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Cyrus Umrigar
Cornell Univ.
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Alberto Vela
CINVESTAV, Mexico
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Henryk Witek
National Chiao Tung Univ., Hsinchu, Taiwan
Analytical form of helium wave function
Summary
Implicit analytical form of the ground state wave function for helium was proposed by Fock in 1954 [1]. Explicit determination of the Fock coefficients turned out to be a complex task; only few of them are found up to date [1–11]. The Fock series can be considered as an extended Taylor series around the triple coalescence point. The current talk will show how the Fock series emerges. In particular, it will show how the logarithmic terms appear in low-order Fock coefficients in order to guarantee the physical behavior (continuity and finiteness) of the resulting wave function. The questions of Fock expansions for helium in states with non-zero angular momentum and for helium without the Born-Oppenheimer approximation will also be addressed.
[1] Fock, V. A. , Norske Vidensk. Selsk. Forh. 1958, 31, 138–152 . (English translation of earlier Russian paper: Fock, V. A. Izv. Akad. Nauk 1954, 18, 161–172.)
[2] Ermolaev, A. M. Vest. Len. Univ. 1961, 16, 19–33.
[3] Abbott, P. C. PhD Thesis, Univ. Western Australia, Perth 1986.
[4] Abbott, P. C.; Maslen, E. N. J. Phys. A 1987, 20, 2043-2075.
[5] Gottschalk, J. E.; Abbott, P. C.; Maslen, E. N.; J. Phys. A 1987, 20, 2077-2104.
[6] Gottschalk, J. E.; Maslen, E. N. J. Phys. A 1987, 20, 2781-2803.
[7] Pluvinage, P. J. Physique 1982, 43, 439-458.
[8] Forrey, R. C. Phys. Rev. A 2004, 69, 022504.
[9] Liverts, E. Z. Phys. Rev. A 2014 89, 032506.
[10] Liverts, E. Z.; Barnea, N. Phys. Rev. A 2015, 92, 042512.
[11] He, B.-H.; Witek, H. A. J. Chin. Chem. Soc. 2016, 63, 69-82.
Xin Xu
Fudan University, China
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Weitao Yang
Duke University, US
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Dominika Zgid
Univ. Michigan, US
Title
Summary
[1] Popelier, P. L. A.; Brémond, É. A. G. Int.J.Quant.Chem. 2009, 109, 2542.
Posters
Grids are 1.2 m wide x 2.4 m high. Poster size is recommended of 1m wide x 1.5 m high.
Please add abstracts in Surname alphabetical order
María Luisa Cerón
Universidad Finis Terrae. Escuela de Ingeniería. Av. Pedro de Valdivia 1509, Providencia, Santiago. Chile
Application of Dual Descriptor to understand the activity of Cu/ZrO2 catalysts in the water gas shift reaction
A comparative theoretical study applying Dual Descriptor[1] has been performed using Water Gas Shift reaction[2], catalyzed by copper supported on monoclinic and tetragonal zirconia. The Dual Descriptor and thermodynamic considerations were used to understand the structural effects that occur in the reaction when it is catalyzed by Cu on both zirconia phases. For these systems were found that the formation of carbonates in the Cu supported on tetragonal zirconia the presence of carbonates necessary for the decomposition of the formates allowing the dehydrogenation this effect is consistently with experimental results[3].
1. C. Morell, A. Grand, A. Toro-Labbé, J. Phys. Chem. A. 2005, 109, 205.
2. M. Rhodes, A. Bell, J. Catal. 2005, 233, 198.
3. G. Águila, S. Guerrero, P. Araya, Catal. Comm., 2008, 9, 2550.
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Eduardo Chamorro
Universidad Andres Bello. Departamento de Ciencias Químicas. Facultad de Ciencias Exactas. 8370146 Santiago. Chile
Theoretical scales of electrophilicity and nucleophilicity.
The suitability of intrinsic (i.e., electronic) relative indices for quantifying electrophilicity and nucleophilicity responses [1-4] is critically examined. Theoretical results are discussed within the framework of experimental reactivity categorization based on the linear free energy methodology developed by Mayr and coworkers [5-9]. The polar nucleophilic/electrophilic activation (as measured through simple descriptors) is shown to be a key factor driving the initial rate-determining steps of the electrophile-nucleophile coupling.
[1] Chamorro, E.; Melin, J. On the Intrinsic Reactivity Index for Electrophilicity/Nucleophilicity Responses. J. Mol. Mod. 2015, 21. DOI: 10.1007/s00894-015-2608-2.
[2] Chamorro, E.; Duque-Norena, M.; Notario, R.; Perez, P. Intrinsic Relative Scales of Electrophilicity and Nucleophilicity. J. Phys. Chem. A. 2013, 117, 2636-2643.
[3] Chamorro, E.; Duque-Norena, M.; Perez, P. A Comparison between Theoretical and Experimental Models of Electrophilicity and Nucleophilicity. J. Mol. Struct.-Theochem. 2009, 896, 73-79.
[4] Chamorro, E.; Duque-Norena, M.; Perez, P. Further Relationships between Theoretical and Experimental Models of Electrophilicity and Nucleophilicity. J. Mol. Struct.-Theochem. 2009, 901, 145-152.
[5] Mayr, H.; Ofial, A. R. A Quantitative Approach to Polar Organic Reactivity. SAR QSAR Environ. Res. 2015, 26, 619-646.
[6] Mayr, H. Reactivity Scales for Quantifying Polar Organic Reactivity: The Benzhydrylium Methodology. Tetrahedron. 2015, 71, 5095-5111.
[7] Mayr, H.; Ofial, A. R. Do General Nucleophilicity Scales Exist? J. Phys. Org. Chem. 2008, 21, 584-595.
[8] Mayr, H.; Ofial, A. R. Kinetics of Electrophile-Nucleophile Combinations: A General Approach to Polar Organic Reactivity. Pure Appl. Chem. 2005, 77, 1807-1821.
[9] Mayr, H.; Patz, M. Scales of Nucleophilicity and Electrophilicity - a System for Ordering Polar Organic and Organometallic Reactions. Angewandte Chemie-International Edition in English. 1994, 33, 938-957.
Macarena Muñoz
University of Chile
How predictive could alchemical derivatives be?
One of the main challenges in materials science is the rational design of compounds, i.e., establishing experimental and theoretical protocols for the design of materials with properties optimized for specific applications. From the theoretical point of view, and in particular electronic structure, the challenge is enormous. To ilustrate this it is sufficient to note the vastness of the "chemical space" [1-3], that is, the set of plausible stable compounds that can be made with elements of the periodic table. Conservative estimations of only a subset of possible small organic molecules lead to the conclusion that this space contains much more than 10⁶⁰ compounds [4]. This work shows that alchemical transformations [5,6] are efficient alternative to explore the energetic landscape of chemical space. Specifically, we show that alchemical derivatives can be used as an efficient screening of the potential stable isomers of the Al13-nSin cluster. We reveal the importance of “electron transfer” effects by comparing isoelectronic and non-isoelectronic alchemical transformations.
[1] P. Kirkpatrick and C. Ellis, Nature 432, 823 (2004).
[2] C. M. Dobson, Nature 432, 824 (2004).
[3] O. A. Von Lilienfeld and M. E. Tuckerman. The Journal of Chemical Physics 125, 154104 (2006).
[4] R. S. Bohacek, C. McMartin, and W. C. Guida, Medicinal Research Reviews 16, 3 (1996).
[5] O. Anatole von Lilienfeld, The Journal of Chemical Physics 131, 164102 (2009).
[6] M. to Baben, J. O. Achenbach, and O. A. von Lilienfeld. The Journal of Chemical Physics 144, 104103 (2016).
Wilver A. Muriel
National University of Colombia, Medellín
Molecular Dynamic Study Of The Excited State Intermolecular Proton Transfer Of 2-Salicylideneantrhylamine In The First Excited Stated
The main challenge for designing photo-active material is to understand processes that follow after light is absorbed. When a molecule absorbs light, both the distribution of the electrons and nuclei change This causes changes in the physical and chemical properties of the molecule, such as potential energy, molecular geometry, polarizability, charge distribution, etc.. Understanding these processes is essential when designing photo-active materials. This poster presents a study of the intramolecular proton transfer in the first excited state of the 2-salicylideneanthrylamine. In order to elucidate dynamic processes in the molecule in question we have used time-dependent density functional theory (TD-DFT) molecular dynamics.
Patricia Perez
Universidad Andres Bello. Departamento de Ciencias Químicas. Facultad de Ciencias Exactas. 8370146 Santiago. Chile
Carbenoid-type reactivity of nitrile ylides in [3+2] cycloaddition reactions towards electron-deficient ethylenes
The [3+2] cycloaddition (32CA) reaction of nitrile ylide (NY) with an electron-deficient ethylene is studied at the MPWB1K/6-31G(d) computational level. A structural analysis of NY shows a carbenoid (cb) structure, allowing its participation in cb-type 32CA reactions. In gas phase, this 32CA reaction is not stereoselective and has low regioselectivity. Inclusion of solvent effects does not modify the activation energy, but increases the meta regioselectivity in clear agreement with the experimental outcomes. Electron localisation function (ELF) topological analysis for the formation of the two C-C single bonds along the four competitive channels associated with this 32CA reaction makes it possible to characterise two dissimilar mechanisms.
1. L.R. Domingo, M. Ríos-Gutiérrez, M. Duque-Noreña, E. Chamorro, P. Pérez.
Theoret. Chem. Acc., 2016, 135,160.
Osvaldo Yañez
Doctorado en Fisicoquímica Molecular, Universidad Andrés Bello, República #275, Santiago-Chile
A Simple Hybrid Algorithm for Exploring the Potential Energy Surface of Clusters and Molecules
The development of optimization strategies (local and global optimization) is a subject of great importance in diverse fields, including the physical sciences (for example, protein folding and atomistic structural determination of macro-molecules and clusters). The main difficulty is that the global extremum of a real multivariate function is actually a local property, thus requiring an exhaustive search. Furthermore, proving that the global extremum has indeed been found seems to be a rather unattainable task for most systems of interest. There were several algorithms proposed for solving this problem. The most popular ones being simulated annealing1, genetic algorithms2, and particle swarm optimization3. While all these methods were effective for calculation of relatively small molecules, they proved to be ineffective when we tried to deal with larger molecules containing more than 12 atoms. The main objective of this work is to build larger atomic clusters using molecular fragments. For this purpose, we implemented a modification to the Kick program developed by Addicoat and Metha4 and Steepest Descent algorithm; by using adequate molecular fragments confined in arbitrarily selected spaces. The performance of this approximation was evaluated in the theoretical design of Lithium-Silicon nanowires, using the most stable isomers of the previously reported Si5Li6 cluster. The Si-Li nanomaterials are important for technological applications in ion-Li batteries for increasing their energy storage capability.
Acknowledgements:
The author thanks CONICYT for a Doctoral fellowship.
[1] Kirkpatrick, S.; Gelatt, C. D.; Vecchi, M. P. Optimization by Simulated Annealing. Science (80-. ). 1983, 220 (4598), 671–680.
[2] Alexandrova, A. N.; Boldyrev, A. I. Search of the Lin 0/+1/-1 (n=5-7) Lowest-Energy Structures Using the Ab-Initio Gradient Embedded Genetic Algorithm (GEGA). Elucidation of the Chemical Bonding in the Lithium Clusters. J. Chem. Theory Comput. 2005, 1, 566.
[3] Call, S. T.; Zubarev, D. Y.; Boldyrev, A. I. Global Minimum Structure Searches via Particle Swarm Optimization. J. Comput. Chem. 2007, 28 (7), 1177–1186.
[4] Addicoat, M. A.; Metha, G. F. Kick: Constraining a Stochastic Search Procedure with Molecular Fragments. J. Comput. Chem. 2009, 30 (1), 57–64.566.