The response of a chaotic Chua's electronic circuit and that of an atom sho
w interesting common features. Starting from the comparison of the qualitat
ive behavior of bifurcation diagrams and electronic spectroscopic series of
atoms we associate order-chaos transition with those of an electron passin
g from a quantized to a continous energy spectrum. The resulting atomic mod
el suggests an analogy between the synchronization of two Chua's atoms and
chemical covalent bonding.