Research

I am part of Prof. Marivi Fernandez-Serra’s group at Stony Brook University. We do computational condensed matter physics, with a focus on liquid water and ice. See the group webpage for more info.

Current project:
I am currently working on simulating water from “first principles”, ie. from the laws of quantum mechanics. The usual technique that physicists use to approximate the quantum mechanics of electrons in condensed matter systems, density functional theory, does not work well for water and much work is being done to understand its shortcomings. One usual assumption is that only electrons need to be treated quantum mechanically. We argue that both electrons and nuclei need to be treated quantum mechanically, and that density functionals should be tested with nuclear quantum effects included. Our custom code implements a novel algorithm which greatly speeds up the calculation of nuclear quantum effects with only minor losses in accuracy. Accurate first principles simulations are important for developing energy materials and in computational drug design.

My scientific publications:

3. Elton, D. C. and Fernandez-Serra, M.-V. “The hydrogen bond network of water supports propagating optical phonon-like modesNat. Comm. 7, 10913 (2016) [arXiv.org]
We show that on subpicosecond time scales optical phonon modes can propagate through the hydrogen bond network of water over relatively long distances (2-4 nm). For the first time we study the LO-TO splitting in water’s dielectric spectra and show how this splitting can be related to local structure.We point out a previously unnoticed discrepancy in the Raman spectra peak assignment and offer a solution.

2. Elton, D. C. and Fernandez-Serra, M.-V. “Polar nanoregions in water – a study of the dielectric properties of TIP4P/2005,TIP4P/2005f and TTM3FJ. Chem. Phys., 140, 124504 (2014) [arXiv.org]
We present a critical comparison of the dielectric properties of three types of water model used in molecular dynamics – rigid, flexible, and polarizable. To better understand the dielectric properties of water we make a novel analogy to the physics of polar nanoregions in relaxor ferroelectric materials. We argue that polarizability is essential to accurately reproducing the dipolar ordering of the liquid and how it changes with temperature. 

1. J. J. Podesta, M. A. Forman, C. W. Smith, D. C. Elton, and Y. Malecot, “Accurate Estimation of Third-Order Moments from Turbulence Measurements“, Nonlin. Proc. Geophys., 16, 99 (2009) [arXiv.org]