NERSCPowering Scientific Discovery Since 1974

Neil Mehta

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Neil Mehta Ph.D.
Postdoctoral Researcher
NESAP for Simulations: Exaalt MD project
NERSC

Research Interests

  • High performance computing for particle based methods.
  • Computational simulations (quantum chemistry, molecular dynamics, and kinetic Monte Carlo) to predict solid-liquid and liquid-liquid interface properties.
  • Exascale capable, high-performance interatomic ML assisted potentials.
  • User applications for quantum computing.

Education

2014-2019       Ph.D. in Aerospace Engineering - The University of Illinois at Urbana-Champaign

2011-2013       Master of Sciences in Aerospace Engineering - The Pennsylvania State University

2005-2009       Bachelor of Engineering in Mechanical Engineering - University of Mumbai

 Professional Experience

  • 2020 - Present : I am a member of the Exaalt MD team at NERSC working on TestSNAP, which is a high-fidelity, machine learning based interatomic potential. I am currently working on computational and algorithm improvements to the TestSNAP OpenMP 4.5 version using roofline analysis. Another aspect of my work is the investigation of data flow between c++ and pytorch.
  • 2015 - 2020 : As a research assistant at The University of Illinois at Urbana Champaign, I investigated the role of long-range Coulomb interactions on electrospray emissions. I developed an octree-based Coulomb interaction method to account for long-range Coulomb interactions which are necessary when performing molecular dynamics simulations of electrosprays. I also determined the relationship between Coulomb interactions, hydrogen bond, energy stored in the covalent bonds, angles and the electric field strength required to generate stable electrospray ionization. These electrospray simulations are computationally expensive and therefore,I developed a coarse-grained potential for ethylammonium nitrate, which is one of the ionic liquid used for electrosprays. In this project, the role of boundary conditions and domain periodicity was also explored.
  • 2011 - 2015 : As a research assistant at The University of Illinois at Urbana Champaign and prior to that at The Pennsylvania State University, I investigated the role of gas and surface species, incidence angle and velocity on the post-collisional energy and reflection angles using molecular dynamics simulations of N2and argon collisions on a highly ordered pyrolytic graphene (HOPG) and quartz surfaces.The energy transfer between gas and surfaces was quantified using energy accommodation coefficient. The physics of gas-surface interaction is very different compared to that observed for large particulate-surface interactions. I also studied these large particulate interactions using ice-like argon and amorphous silica collisions on HOPG and quartz surfaces. To model this process on a larger length scale, I developed kinetic Monte Carlo (KMC) simulation rules to model realistic HOPG behavior.

Publications

  • Multiscale modeling of damaged surface topology in a hypersonic boundary, Mehta, N., and Levin, D., Journal of Chemical Physics, September 2019.
  • Electrospray molecular dynamics simulations using an octree-based Coulomb interaction method, Mehta, N., and Levin, D., Physical Review E, March 2019.
  • Non-Reactive Scattering of N2from Layered Graphene Using Molecular Beam Experiments and Molecular Dynamics, Mehta, N., Murray, V., Xu, C., Levin, D., and Minton, T., Journal of Physical Chemistry C, March 2018.
  • Sensitivity of electrospray molecular dynamics simulations to long-range Coulomb interaction models, Mehta, N., and Levin, D., Physical Review E, March 2018.
  • Molecular Dynamics Electrospray Simulations of Coarse-Grained EAN and EMIM-BF4Mehta, N., and Levin, D., Aerospace, December 2017.
  • Comparison of two protic ionic liquid behaviors in the presence of an electric field using Molecular Dynamics, Mehta, N., and Levin, D., Journal of Chemical Physics, December 2017.
  • Molecular-dynamics-derived gas–surface models for use in direct-simulation Monte Carlo, Mehta, N., and Levin, D., Journal of Thermophysics and Heat Transfer, April 2017.

Full list of publications and conferences can be accessed from: https://scholar.google.com/citations?user=eAFnJSAAAAAJ&hl=en

My Ph.D. thesis "Use of molecular dynamics simulations to study the impact of weak to strong non-covalent chemical interactions" can be accessed from: https://www.ideals.illinois.edu/handle/2142/107838