Constructing H H H Molecular orbitals Pi molecular orbitals are the sideways overlap of p orbitals p orbitals have 2 lobes. Plus(+)and minus C indicate the opposite phases of the wave unction, not electrical charge When lobes overlap constructively, ( and +,or-and -)a bonding Mo is formed When and -lobes overlap, waves cancel out and a node forms; antibonding Mo.=> Chaper 15
Chaper 15 6 Constructing Molecular Orbitals • Pi molecular orbitals are the sideways overlap of p orbitals. • p orbitals have 2 lobes. Plus (+) and minus (-) indicate the opposite phases of the wave function, not electrical charge. • When lobes overlap constructively, (+ and +, or - and -) a bonding MO is formed. • When + and - lobes overlap, waves cancel out and a node forms; antibonding MO. =>
丌1 MO for1,3- Butadiene≈a H Lowest energy All bonding interactions Electrons are delocalized over four nuclei > Chaper 15
Chaper 15 7 1 MO for 1,3-Butadiene • Lowest energy. • All bonding interactions. • Electrons are delocalized over four nuclei. =>
H H T2 MO for 1, 3-Butadiene 2 bonding interactions 1 antibonding interaction 兀 a bonding mo > Chaper 15
Chaper 15 8 2 MO for 1,3-Butadiene • 2 bonding interactions • 1 antibonding interaction • A bonding MO =>
I* MO for 1, 3-Butadiene -_u H Antibonding mo Empty at ground兀* state Two nodes => Chaper 15
Chaper 15 9 3 * MO for 1,3-Butadiene • Antibonding MO • Empty at ground state • Two nodes =>
H H H MO for 1.3-Butadiene All antibonding interactions Highest energy Vacant at ground state > Chaper 15 10
Chaper 15 10 4 * MO for 1,3-Butadiene • All antibonding interactions. • Highest energy. • Vacant at ground state. =>