Short range order orientation in a liquid

SPEAKER: Andrés Henao (DFEN, Universitat Politècnica de Catalunya)
TITLE: Short range order orientation in a liquid
DATE / PLACE: September 27th sala de reunions B5-211
ABSTRACT:
We present a detailed study on the liquid structure of hexachloroethane (C2Cl6) within the first shell using the proper Euler-angles convention[1]  based on the complete knowledge of the six degrees of freedom for the molecule emphasizing that we are going to use a rigid molecule model, only the translational and orientational dispositions are taken into account. This type of analysis has been used before and it is ideal to study the short range order, for instance see [2]. Molecular dynamics is used and the van der Waals picture of a liquid is taken as the main phenomenology. Particular attention is paid to the first neighbour studying the distance of the center of mass (CM) and relative orientation arrangements. The distance dependence of the orientation and location of closer neighbours is studied up to the fourth neighbour (the maximum of first peak of the CM radial distribution function) obtaining two competing orientational structures. This results highlights the need of improving our understanding of the static structure of liquids, that can be rather complex.

[1] H. Goldstein, C. Poole and J.L Safko, Classical Mechanics, third edition ed. (Addision Wesley, san Francisco, 2002).
[2] L. C. Pardo, J. Ll. Tamarit and N. Veglio, Phys. Rev. B. 76, 134203(2007).