Electron shells, in the context of atomic structure, are not considered to be point particles. Rather, they represent regions of space around an atomic nucleus where electrons are most likely to be found.
According to the quantum mechanical model of the atom, electrons are described by wave functions that determine the probability distribution of finding an electron at a particular location. These wave functions are solutions to the Schrödinger equation, which describes the behavior of quantum particles.
The wave functions associated with electrons in atoms typically exhibit spatial distributions that are spread out rather than localized at a single point. The electron shells, also known as energy levels or orbitals, are defined by specific quantum numbers and describe the regions of higher probability density where electrons are likely to be located.
The shapes of the electron shells are characterized by various orbital types, such as s, p, d, and f orbitals, which have different spatial distributions and orientations. These orbitals are not points, but rather regions of space with specific geometries.
It is worth noting that the concept of a "point particle" is an idealized notion used in classical physics to simplify calculations. However, at the quantum level, particles are described by wave functions that account for their wave-like nature and the inherent uncertainty in their positions.
Therefore, electron shells are not considered to be point particles. They represent the spatial distribution of electron probability densities in atoms, as described by quantum mechanics.