Stochastic search for isomers on a quantum mechanical surface
Related Experiment Video
Updated: Aug 16, 2026

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
1Department of Chemistry, Yale University, New Haven, CT 06520, USA.
Abstract:
In studying molecules with unusual bonding and structures, it is desirable to be able to find all the isomers that are minima on the energy surface. A stochastic search procedure is described for seeking all the isomers on a surface defined by quantum mechanical calculations involving random kicks followed by optimization. It has been applied to searching for singlet structures for C6 using the restricted Hartree-Fock/6-311G basis set. In addition to the linear chain and ring previously investigated, 11 additional structures (A-K) were located at this level. These provide a basis for discussing qualitative bonding motifs for this carbon cluster. The application of a similar idea to searching for transition states is discussed.
Related Concept Videos
Hybridization of Atomic Orbitals I
Hybridization of Atomic Orbitals II
Stereoisomerism of Cyclic Compounds
Woodward–Hoffmann Selection Rules and Microscopic Reversibility
Thermal Sigmatropic Reactions: Overview
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in 1,5-hexadiene, referred to as...
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

