Ethylene Pi MOs (antibonding) destructive energy (bonding)= Copyright2010 Pearson Prentice Hall,Inc The combination of two p orbitals must give two molecular orbitals. Constructive overlap is a bonding MO. Destructive overlap is an antibonding MO. Chapter 15 7Chapter 15 7 Ethylene Pi MOs ▪ The combination of two p orbitals must give two molecular orbitals. ▪ Constructive overlap is a bonding MO. ▪ Destructive overlap is an antibonding MO