# Crystalline membrane morphology beyond polyhedra

## TL;DR

This study explores how magnetic interactions can induce and control complex, switchable morphologies in crystalline membranes, enabling shape manipulation for potential targeted delivery applications.

## Contribution

It introduces a novel magnetoelastic membrane system where magnetic fields control membrane shape and symmetry, surpassing traditional polyhedral constraints.

## Key findings

- Magnetic interactions induce concave membrane morphologies.
- Symmetry decreases from 5-fold to 1-fold with increasing magnetic field.
- Membrane shapes can be reversibly switched between convex and concave.

## Abstract

Elastic crystalline membranes exhibit a buckling transition from sphere to polyhedron. However, their morphologies are restricted to convex polyhedra and are difficult to externally control. Here, we study morphological changes of closed crystalline membrane of super-paramagnetic particles. The competition of magnetic dipole-dipole interactions with the elasticity of this magnetoelastic membrane leads to concave morphologies. Interestingly, as the magnetic field strength increases, the symmetry of the buckled membrane decreases from 5-fold to 3-fold, to 2-fold and, finally, to 1-fold rotational symmetry. This gives the ability to switch the membrane morphology between convex and concave shapes with specific symmetry and provides promising applications for membrane shape control in the design of actuatable micro-containers for targeted delivery systems.