When electrons drift towards an atom with a very high electronegativity, then that atom will experience an increase in negative characteristics. It will NOT become an anion, but will be somewhat negative. Likewise, if electrons drift away from a low electronegativity atom, then that atom will experience a loss of negative characteristics or develops a set of positive characteristics. It does NOT become a cation. Instead, it is somewhat positive.
Partial charges exist in polar covalent systems.
Ionic systems do not have partial charges. Polar Covalent Bond A Polar Covalent Bond occurs when two atoms bond that have differences in electronegativity values between 1.7 and 0.3. Under these conditions the atoms will share electrons, but the sharing is decidely uneven. One of the atoms will dominate in the sharing process and develop a partial negative charge. The other atom will develop a partial positive charge because of the shared electrons drifting away from it.