It is Bohr and Mottelson's discovery that the atomic nuclei is not spherical. This is quite surprising.
A natural question is then, can the atom also be non-spherical?
It is Bohr and Mottelson's discovery that the atomic nuclei is not spherical. This is quite surprising.
A natural question is then, can the atom also be non-spherical?
The reasons for the existence of pear shaped nuclei are discussed in Why are pear-shaped nuclei possible? and Do pear-shaped nuclei really have anything to do with time travel? The tl;dr version is that the weak force is important in determining the nucleus shape and the weak force violates parity, so it's possible to have a ground state that is not parity symmetric.
However the weak force is too short range to have any effect on the shape of the electronic structure of an atom, so atoms are spherical to within experimental error. In principle there will be deviations from spherical symmetry, but in practice these will be too small to be measurable.