Molecular dynamics simulation of the fragile glass former ortho-terphenyl: a flexible molecule model

TL;DR

This paper develops a detailed molecular dynamics model of orthoterphenyl, a fragile glass former, and compares simulation results with experimental data and Mode Coupling Theory predictions.

Contribution

It introduces a realistic molecular model with harmonic and anharmonic interactions and provides extensive simulation data on static and dynamic properties.

Findings

Self-diffusion properties analyzed in detail

Temperature and momentum dependencies characterized

Simulation results compared with experiments and theory

Abstract

We present a realistic model of the fragile glass former orthoterphenyl and the results of extensive molecular dynamics simulations in which we investigated its basic static and dynamic properties. In this model the internal molecular interactions between the three rigid phenyl rings are described by a set of force constants, including harmonic and anharmonic terms; the interactions among different molecules are described by Lennard-Jones site-site potentials. Self-diffusion properties are discussed in detail together with the temperature and momentum dependencies of the self-intermediate scattering function. The simulation data are compared with existing experimental results and with the main predictions of the Mode Coupling Theory.