Question

Question 4 [31] For a diatomic molecule, the electronic wavefunction was descri bed by CA + €pB R (a)Express energy expectation value as a function of c, Ca and integral constants [3] (b) Derive and explain their chemical implications of Coulombic integral (a), Resonance Integral (B), and Overlap Integral (s). [3] (c)What are the key Hückel's approximations for a homonuclear molecule? [4] Question 4 [31]; Contin ued Propene Cyclopropene Cyclopropenyl Cation Using the Hückel molecular orbital theory, wavefunction of electrons in a propene can be described by a linear combinations of atomic orbitals (LCAO) with the 2p orbital(s), being perpendicular to the molecular plane. (d) Derive secular determi na nt for this system. [5 (e) Calculate molecular orbital energies of the electrons in the linear-shape propene and draw the energy level diagram. [5 () Do the same thing as (e) but for a cyclopropene. [5] (g) Is the Cyclopropene stable? How about a cycloprope nyl cation? Explain using molecular energy level diagram. [6]

Answer 1

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