Question

What does it mean to have directional character of bond?

Answer 1

The meaning of bonds being directional is that atoms bonded prefer specific orientations in space relative to one another.Covalent bond show directionality and the reason for this directionality is that bonds are formed by sharing electrons between atoms, or, in other words, as you said, by overlapping the atomic orbitals of participant atom. And usually only few patterns of overlap are possible, consequently, only few spatial arrangements of atom are possible,where as ionic bonds are non directional , because charge is uniform in all direction . An ion is surrounded by other ion from all the direction .Covalent and coordinate bond are formed by one side only hence are directional