PUCHIK: A Python package to analyze aspherical nanoparticles

Accurately describing a nanoparticle's interface is crucial for understanding its internal structure, interfacial properties, and ultimately, its functionality. While current computational methods provide reasonable descriptions for spherical and quasi-spherical nanoparticles, there remains a need for effective models for aspherical structures such as capsules and rod-like systems. This work introduces a new Python Utility for Characterizing Heterogeneous Interfaces and Kinetics (PUCHIK), a novel algorithm developed to describe both sphere-like and aspherical nanoparticles. With an accurate description of the location of the interface of the nanoparticle, this algorithm then allows for various other important quantities (e.g. densities of different atom/molecule types relative to the interface, volume of the nanoparticle, amount of solubilized molecules within the nanoparticle) to be calculated. Our software development focused on providing good performance to computationally demanding projects, while ensuring the methodological approach can be adapted as a protocol for other code implementations.