04/18/2024
By Kwok Fan Chow

The Kennedy College of Science, Department of Chemistry, invites you to attend a Ph.D. Research Proposal defense by Amin Kiani entitled “Computational Techniques for Molecular Interaction Potential Map Creation and Analysis.”

Degree: Doctoral
Location: Olney, Room 522
Date: Tuesday, April 30, 2024
Time: 10 a.m.

Committee:

  • Chair Lawrence M. Wolf, Department of Chemistry, University of Massachusetts Lowell
  • Jerome Delhommelle, Department of Chemistry, University of Massachusetts Lowell
  • Prof. Olof Ramstrom, Department of Chemistry, University of Massachusetts Lowell
  • Prof. Mingdi Yan, Department of Chemistry, University of Massachusetts Lowell

Abstract:
We first detail the creation of intermolecular interaction maps (IMIPs) from the potentials derived from DFT-based methods, with a particular focus on energy decomposition analysis (EDA) and its applications toward insight into electronic structure and reactivity. This work elaborates upon techniques used to construct such maps. Traditionally, potential maps like the electrostatic potential (ESP) are employed to visualize the distribution of molecular properties around a molecule, identifying key regions where specific interactions are predominant. However, this research takes a step forward by incorporating energy decomposition analysis (EDA), which provides a quantifiable analysis of the relative contributions from different interaction types to a molecule’s total energy, thus enabling a more comprehensive understanding of molecular interactions.

We demonstrate the potential utility of our methodology through a series of examples within the LMO-EDA framework. The examples included cover select aromatics and intermolecular interactions, including anion-cation pi interactions, organic reaction selectivity, Lewis acid activation, some select organometallics, and other examples highlighting unique properties and interactions that maps like ESP are unable to uncover. The information provided by these potential maps could be used to guide the development of more efficient and effective analysis and design methodologies for a wide range of applications, including drug design, materials science, and catalysis.

We then elaborate on the application of other decomposition scheme such as the NOCV-ETS and Perturbative Molecular Orbital Interaction (PMO) theory that can be applied to create such surfaces. Finally, we end the first section by presenting a new way of generating surfaces, based not on one density value (the so called “Iso-Value”), but rather variable electron density, which we believe can map local interactions to a finer level of detail and paint a more nuanced picture of the energetic landscape than traditional iso-value based surfaces.

The second portion of this proposal focuses on the development of a quantitative structure selectivity relationship (QSSR) workflow using Molecular Interaction Field (MIF)-based methods. Here, we introduce a new class of 3-D descriptors derived from EDA. These descriptors are designed to offer a more comprehensive representation of electronic interactions, moving beyond the conventional descriptors that primarily probe electrostatic and steric interactions. A key aim of this project is the practical application of our EDA-QSSR model to a specific class of catalytic reactions, particularly focusing on the BINOL-catalyzed formation of N, S-acetals. Preliminary results have shown promise, and we intend to conduct a more thorough study to validate further and demonstrate the robustness of our model.

All interested students and faculty members are invited to attend.