4. (a) Use the simple one-electron molecular orbital method, including overlap, tocalculate the energies of the molecular orbitals of the hydrogen molecule (H₂) interms of a, ß and S?(b) Calculate & given that a = -13.6 eV, that S = 0.6, and that the lowest UV absorptionenergy is 12 eV.(c) Determine the ionisation energy of the bonding molecular orbital in H₂ ? [6 marks]

Answered: Image /qna-images/answer/ba01fe21-ad3c-4d65-8d53-556f9af2e6c9.jpg

4. (a) Use the simple one-electron molecular orbital method, including overlap, to calculate the energies of the molecular orbitals of the hydrogen molecule (H₂) in. terms of a, ß and S? (b) Calculate ß given that a = -13.6 eV, that S = 0.6, and that the lowest UV absorption energy is 12 eV. (c) Determine the ionisation energy of the bonding molecular orbital in H₂ ? [6 marks]

4. (a) Use the simple one-electron molecular orbital method, including overlap, to calculate the energies of the molecular orbitals of the hydrogen molecule (H₂) in. terms of a, ß and S? (b) Calculate ß given that a = -13.6 eV, that S = 0.6, and that the lowest UV absorption energy is 12 eV. (c) Determine the ionisation energy of the bonding molecular orbital in H₂ ? [6 marks]

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 26P: Following the pattern of Figure 6.21, work out the correlation diagram for the BeN molecule, showing...

See similar textbooks

Similar questions

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.
(a) Draw a Lewis diagram for formaldehyde (H,CO), and decide the hybridization of the central carbon atom. (b) Formulate the molecular orbitals for the molecule. (c) A strong absorption is observed in the ultraviolet region of the spectrum and is attributed to a → T* transition. Another, weaker transition is observed at
(b) in a particular photoelectron spectrum using 21.21 ev photons, electrons were ejected with kinetic energies of 11.01 ev, 8.23 ev, and 5.22 ev. Sketch the molecular orbital energy level diagram for the species, showing the ionization energies of the three orbitals.
(a) Use the simple one-electron molecular orbital method, including overlap, to calculate the energies of the molecular orbitals of the hydrogen molecule (H2) in terms of α, β and S?
The ground-state electron configuration of the H; molec- ular ion is (og15)'. (a) A molecule of H absorbs a photon, promoting the electron to the os molecular orbital. Predict what happens to the molecule. (b) Another molecule of H absorbs even more energy promoting the electron to the o,2, molecular orbital. Predict what happens to this molecule.
8) Consider the heteronuclear diatomic molecule, HCl with bonding orbital given by, citation legg W, = 0.205,H +0.98º3p,cI %D ght ventric FULL PRIC where ø is the (normalized) hydrogen 1s orbital and o,, c is the (normalized) chlorine BOG 3pz orbital. Assume that the atomic overlap integral is zero, | WisH W3p.cadt = 0. %3D all space a) Show that the bonding molecular orbital is normalized. Shot 232 PM BOO and B, b) What is the energy of the bonding orbital? Write your answer in terms of a,, ,a,,. T COS which are defined by: АМ Shbt 25PM ght ventric | V1s,H Hw cdt = | 4 1s,H RENT & || all space all space Che pulmc vein | Wis.H HySHdt =a,, and cdt = d3p. 1s, 3 Pz,CI right atriursen Shot 2021-02 5.56 PM pulmonary valve all space all space W étv A APR 4 29 260 Book A DD F11 F10
The FEMO theory of conjugated molecules is crude and marginally better results are obtained with simple Huckel theory. (a) For a linear conjugated polyene with each of N carbon atoms contributing an electron in a 2porbital, the energies Ek of the resulting π molecular orbitals are given by: Ek = α + 2β cos kπ/N+1 k = 1,2,3, ... N Use this expression to estimate the resonance integral β for the series consisting of ethene, butadiene, hexatriene, and octatetraene given that ult raviolet absorptions from the HOMO, which is a bonding π orbital, to the LUMO, which is an antibonding π* orbital, occur at 61 500, 46 080, 39 750,and 32 900 cm- 1, respectively. (b) Calculate the π-electron delocalization energy, Edelcc = Eπ -n(α + β). of octatetraene, where Eπ, is the total π-electron binding energy and n is the total number of π-electrons.
For monocyclic conjugated polyenes (such as cyclobutadiene and benzene) with each of N carbon atoms contributing an electron in a 2p orbital, Huckel theory gives the fol lowing expression for the energies Ek of the resulting π molecular orbitals Calculate the energies of the 1t molecular orbitals of benzene and cyclooctatetraene. Comment on the presenceor absence of degenerate energy levels. (b) Ca lcu late and compare the delocalization energies of benzene and hexatriene using the expression from the preceding problem. What do you conclude from your results? (c) Calculate and compare the delocalization energies of cyclooctatetraeneand (linear) octatetraene. Are your conclusions for th is pair of molecules the same as for the pair of molecules investigated in part (b)?
3
(b) In the construction of the molecular orbital diagram of a polyatomic molecule (SF6), 12 valence electrons are used to occupy 10 MO; account for the origin of the 12 electrons and the 10 MOs
(a) Dihydrogen cation H2+ is commonly found in interstellar space. It can be generated by ionization of dihydrogen molecule H2. What electromagnetic radiation can be used to generate the H2+ cation? (b) Construct an energy level diagram for the molecular orbitals of the H2+ cation. What is the bond order of the HH bond in the H2+ cation? (c) Suggest a spectroscopic method for differentiation of H2 gas and the H2+ cation. Explain your answers.
(a) Sketch the molecular orbitals of the H2- ion and draw itsenergy-level diagram. (b) Write the electron configuration ofthe ion in terms of its MOs. (c) Calculate the bond order inH2-. (d) Suppose that the ion is excited by light, so that anelectron moves from a lower-energy to a higher-energy molecularorbital. Would you expect the excited-state H2- ion to bestable? (e) Which of the following statements about part (d) is correct: (i) The light excites an electron from a bonding orbitalto an antibonding orbital, (ii) The light excites an electronfrom an antibonding orbital to a bonding orbital, or (iii)In the excited state there are more bonding electrons thanantibonding electrons?