Improving the efficiency of branchandbound completesearch NMR assignment using the symmetry of molecules and spectra
Abstract
Nuclear magnetic resonance (NMR) assignment of small molecules is presented as a typical example of a combinatorial optimization problem in chemical physics. Three strategies that help improve the efficiency of solution search by the branch and bound method are presented: 1. reduction of the size of the solution space by resort to a condensed structure formula, wherein symmetric nuclei are grouped together; 2. partitioning of the solution space based on symmetry, that becomes the basis for an efficient branching procedure; and 3. a criterion of selection of input restrictions that leads to increased gaps between branches and thus faster pruning of nonviable solutions. Although the examples chosen to illustrate this work focus on smallmolecule NMR assignment, the results are generic and might help solving other combinatorial optimization problems.
 Authors:
 Ecole Polytechnique Féderale de Lausanne (EPFL), CH11015 Lausanne (Switzerland)
 Chemistry Department, Universidad del Valle, AA 25360 Cali, Valle (Colombia)
 (Colombia)
 MindLab Research Group, Universidad Nacional de Colombia, Bogotá D.C. (Colombia)
 DARMN Research Group, Universidad del Valle, Cali, Valle (Colombia)
 Publication Date:
 OSTI Identifier:
 22416135
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 7; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ALLOCATIONS; BRANCHING RATIO; CHEMICAL PHYSICS; EFFICIENCY; MATHEMATICAL SOLUTIONS; MOLECULES; NMR SPECTRA; NUCLEAR MAGNETIC RESONANCE; OPTIMIZATION; SYMMETRY
Citation Formats
Bernal, Andrés, Patiny, Luc, Castillo, Andrés M., MindLab Research Group, Universidad Nacional de Colombia, Bogotá D.C., González, Fabio, and Wist, Julien, Email: julien.wist@correounivalle.edu.co. Improving the efficiency of branchandbound completesearch NMR assignment using the symmetry of molecules and spectra. United States: N. p., 2015.
Web. doi:10.1063/1.4907898.
Bernal, Andrés, Patiny, Luc, Castillo, Andrés M., MindLab Research Group, Universidad Nacional de Colombia, Bogotá D.C., González, Fabio, & Wist, Julien, Email: julien.wist@correounivalle.edu.co. Improving the efficiency of branchandbound completesearch NMR assignment using the symmetry of molecules and spectra. United States. doi:10.1063/1.4907898.
Bernal, Andrés, Patiny, Luc, Castillo, Andrés M., MindLab Research Group, Universidad Nacional de Colombia, Bogotá D.C., González, Fabio, and Wist, Julien, Email: julien.wist@correounivalle.edu.co. 2015.
"Improving the efficiency of branchandbound completesearch NMR assignment using the symmetry of molecules and spectra". United States.
doi:10.1063/1.4907898.
@article{osti_22416135,
title = {Improving the efficiency of branchandbound completesearch NMR assignment using the symmetry of molecules and spectra},
author = {Bernal, Andrés and Patiny, Luc and Castillo, Andrés M. and MindLab Research Group, Universidad Nacional de Colombia, Bogotá D.C. and González, Fabio and Wist, Julien, Email: julien.wist@correounivalle.edu.co},
abstractNote = {Nuclear magnetic resonance (NMR) assignment of small molecules is presented as a typical example of a combinatorial optimization problem in chemical physics. Three strategies that help improve the efficiency of solution search by the branch and bound method are presented: 1. reduction of the size of the solution space by resort to a condensed structure formula, wherein symmetric nuclei are grouped together; 2. partitioning of the solution space based on symmetry, that becomes the basis for an efficient branching procedure; and 3. a criterion of selection of input restrictions that leads to increased gaps between branches and thus faster pruning of nonviable solutions. Although the examples chosen to illustrate this work focus on smallmolecule NMR assignment, the results are generic and might help solving other combinatorial optimization problems.},
doi = {10.1063/1.4907898},
journal = {Journal of Chemical Physics},
number = 7,
volume = 142,
place = {United States},
year = 2015,
month = 2
}

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