Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Alexandros Chremos

NIST Postdoctoral Research Associate

Research Interests

Polyelectrolytes and counter-ions

Synthetic and biological polymers (e.g., DNA and proteins) are challenging to model due to the formation of dynamic layers of associated water and counter-ion particles in the proximity of the polyelectrolyte. The dynamics of these polyelectrolytes are predominantly influenced by the associating species in these layers. This association phenomenon and the coupling to the polymer dynamics is poorly understood. Molecular dynamics of bead-spring model and an explicit solvent are used to develop quantitative metrologies for quantifying this complex interactions between the polyelectrolytes and these dynamic layers of associating particles.

Impact of Molecular Shape in Dense Polymeric Materials

We investigate the role of molecular shape in the thermodynamics and in the dynamics of dense fluids. Towards understanding the impact of molecular shape, ZENO is applied to compute shape related characteristics including the hydrodynamic radius and sphericity, and molecular dynamics simulations with a bead-spring model are used to investigate the thermodynamical and dynamical behavior of distinct molecular topologies such as linear chains, stars, and rings.

 

For a complete publication list see:

Google Scholar Profile

Publications

Dynamic Heterogeneity and Collective Motion in Star Polymer Melts

Author(s)
Jack F. Douglas, Jinpeng Fan, Hamed Emamy, Francis W. Starr, Alexandros Chremos
While glass formation of linear chain polymers has been widely explored, comparatively little is known about glass formation in star polymer melts. We study the

Superionic UO2: A Model Anharmonic Crystalline Material

Author(s)
Jack F. Douglas, Hao Zhang, Xinyi Wang, Alexandros Chremos
Crystalline materials at elevated temperatures and pressures can exhibit properties more reminiscent of simple liquids than ideal crystalline materials, an
Created June 6, 2019