Question
Physical Chemistry Question on Molecular structure and Chemical bonding
Ψ1, Ψ2, Ψ3 and Ψ4 are four Hückel molecular orbitals of benzene with orbital energies E1, E2, E3, and E4, respectively.
Ψ1 = 21(ФB + ФC - ФE - ФF)
Ψ2 = 6−21(ФA - ФB + ФC - ФD + ФE - ФF)
Ψ3 = 6−21(ФA + ФB + ФC + ФD + ФE - ФF)
Ψ4 = 12−21(2ФA + ФB - ФC - 2ФD - ФE + ФF)
The correct order of the orbital energies is
(The six carbon atoms of benzene are denoted by A to F and ФJ, is the 2pz, orbital of Jth carbon of benzene.)
A
E1 < E2 = E3 < E4
B
E4 < E1 = E3 < E2
C
E3 < E1 = E4 < E2
D
E3 < E2 < E1 = E4
Answer
E3 < E1 = E4 < E2
Explanation
Solution
The correct option is (C) : E3 < E1 = E4 < E2.