化学问题一道(AP)(010)Explain why two atoms cannot form three pi bonds.

When the three p Atomic Orbitals on one atom approach those on another atom, one of the p-orbitals (such as px) must make a head-on approach with the px on the other atom to form a sigma(sub-p) molecular orbital. Only the two other p-orbitals, the py and pz, can overlap side-by-side to give pi bonds, the pi(sub y) and pi(sub z).

When the three p AO's on one atom approach those on another atom,one of the p's,e.g.the px,must make a head-on approach with the px on the other atom to form a sigama p MO.Only the two other p's,the p...