# New Coarse-Grained Models to Describe the Self-Assembly of Aqueous Aerosol-OT

## TL;DR

This paper introduces new simplified models to study how AOT surfactant forms structures in water, enabling faster and more efficient simulations.

## Contribution

The development of three coarse-grained models for AOT using the Martini 3 force field to simulate self-assembly behaviors.

## Key findings

- The models accurately reproduce AOT self-assembly at different concentrations.
- Vesicle formation from bicelles above the critical vesicle concentration is demonstrated.
- The models enable studying large-scale structures and long time scales not feasible with all-atom simulations.

## Abstract

Aerosol-OT (AOT)
is a very versatile surfactant that
exhibits a
plethora of self-assembly behaviors. In particular, due to its double-tail
structure, it is capable of forming vesicles in water. However, the
size of these structures, and the time scales over which they form,
make them difficult to study using traditional all-atomistic molecular
dynamics simulations. Here, three coarse-grained models are developed
for AOT with different levels of detail. The models take advantage
of the Martini 3 force field, which enables 2:1 mappings to be employed
for the tail groups. It is shown that these models are able to reproduce
the self-assembly behavior of AOT in water at three concentrations:
below the critical vesicle concentration (CVC), above the CVC, and
in the lamellar phase. The results also demonstrate the formation
of vesicles from bicelles above the critical vesicle concentration,
which is an important milestone for the continued study of vesicle
behavior.