This molecule is planar, so we can approximate electrons as being confined inside a square. What are energy states/levels and corresponding degeneracies of a particle in a square of side a? Porphyrin molecules have 18 T electrons. Consider each state as a molecular orbital. Fill those electrons in the corresponding molecular orbitals. If the length of the molecule is 850 pm, what is the lowest energy absorption of the porphyrin molecules? (The experimental value 17000 cm-¹).

This molecule is planar, so we can approximate electrons as being confined inside a square. What are energy states/levels and corresponding degeneracies of a particle in a square of side a? Porphyrin molecules have 18 T electrons. Consider each state as a molecular orbital. Fill those electrons in the corresponding molecular orbitals. If the length of the molecule is 850 pm, what is the lowest energy absorption of the porphyrin molecules? (The experimental value 17000 cm-¹).

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter6: Quantum Mechanics And Molecular Structure

Section: Chapter Questions

Problem 64P: For each of the following molecules, construct the MOs from the 2pz atomic orbitals perpendicular...

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For each of the following molecules, construct the MOs from the 2pz atomic orbitals perpendicular to the plane of the carbon atoms. (a) Cyclobutadiene HC (b) Allyl radical Indicate which, if any, of these orbitals have identical energies from symmetry considerations. Show the number of electrons occupying each MO in the ground state, and indicate whether either or both of the molecules are paramagnetic. Assume that the C atoms in the allyl radical are all sp2 hybridized.
According to recent spectroscopic results, nitramide is a nonplanar molecule. It was previously thought to be planar. (a) Predict the bond order of the NN bond in the nonplanarstructure. (b) If the molecule really were planar after all, what would be the bond order of the NN bond?
Explain why 1g is the ground state for H2+ . By combining your answer with the answer to Problem 5, what conclusions can you draw about the molecular orbital description of the bond in H2+ ?
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Following the pattern of Figure 6.21, work out the correlation diagram for the BeN molecule, showing the relative energy levels of the atoms and the bonding and antibonding orbitals of the molecule. Indicate the occupation of the MOs with arrows. State the order of the bond and comment on the magnetic properties of BeN.
The MO of the ground state of a heteronuclear diatomicmoleculeAB is mol=CAA+CBB If a bonding electron spends 90% of its time in an orbital A on atom A and 10% of its time in B on atom B, what are the values of CA and CB ? (Neglect the overlap of the two orbitals.)
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The highest occupied molecular orbital of a molecule isabbreviated as the HOMO. The lowest unoccupied molecularorbital in a molecule is called the LUMO. Experimentally,one can measure the difference in energy betweenthe HOMO and LUMO by taking the electronic absorption(UV-visible) spectrum of the molecule. Peaks in theelectronic absorption spectrum can be labeled as p2p9p2p*,s2s9s2s*, and so on, corresponding to electrons being promotedfrom one orbital to another. The HOMO-LUMO transitioncorresponds to molecules going from their groundstate to their first excited state. (a) Write out the molecularorbital valence electron configurations for the ground stateand first excited state for N2. (b) Is N2 paramagnetic or diamagneticin its first excited state? (c) The electronic absorptionspectrum of the N2 molecule has the lowest energypeak at 170 nm. To what orbital transition does this correspond?(d) Calculate the energy of the HOMO-LUMO transitionin part (a) in terms of kJ/mol. (e) Is the…
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schematically show the pi electronic enery levels of hexatriene
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