[qstong0601]

SbF6 is a covalent molecule in which element Sb and F share their valence electrons.  according to the difference of electronegativity, it said if the difference is greater than 1.7, the bond among the two elements will be ionic rather than covalent. in this case the electronegativity of F is 4.0, and the electronegativity of Sb is 1.9. that said the difference of electronegativity is 2.1, which implies that SbF6 is not supposed to be a covalent molecule, it should be a ionic molecule rather. in reality, SbF6 is a covalent molecule though. so what type of bond is between Sb and F?