Electronic states of diatomic molecules, Franck–Condon principle, Hund's coupling schemes, evaluation of molecular constants from vibrational spectral data - Question Bank
1. The intensity of a vibronic transition is proportional to the square of the transition dipole moment and the:
2. In the context of Hund's coupling schemes, the angular momentum quantum number Σ represents:
3. The evaluation of molecular constants like ωe and ωexe from vibrational spectral data allows for the construction of:
4. The study of electronic states, Franck-Condon principle, and Hund's coupling schemes is fundamental to understanding:
5. Which molecular constant determines the energy spacing between adjacent rotational levels within a given vibrational state?
6. If a diatomic molecule has a significantly different equilibrium bond length in the excited electronic state compared to the ground state, the vibrational structure of the electronic band will likely show:
7. The rotational fine structure superimposed on vibrational bands in electronic spectra provides information about:
8. What information can be directly obtained from the vibrational spacing in the IR or Raman spectrum of a diatomic molecule, assuming harmonic motion?
9. The dissociation energy (De) of a diatomic molecule is related to the equilibrium vibrational frequency (ωe) and the anharmonicity constant (ωexe) by:
10. Isotope substitution in a diatomic molecule primarily affects its:
11. The rotational constant (Be) of a diatomic molecule is inversely proportional to its:
12. In Hund's case (a), the quantum number Λ represents:
13. Which Hund's case is most appropriate for heavy diatomic molecules where spin-orbit coupling is very strong?
14. Hund's coupling schemes are important for understanding:
15. The '0-0 band' in an electronic spectrum corresponds to a transition from the vibrational level v'=0 in the ground electronic state to:
16. If the potential energy curves of the ground and excited electronic states of a diatomic molecule are nearly identical in shape and position, what is expected for the vibrational transition probabilities?
17. The selection rule for vibrational transitions in the harmonic oscillator approximation is:
18. A vibronic transition refers to a transition that involves changes in both:
19. Electronic transitions in diatomic molecules involve changes in:
20. What is the primary motivation for studying the electronic states of diatomic molecules?
21. The anharmonicity constant (ωexe) is usually a positive or negative value?
22. The equilibrium vibrational frequency (ωe) can be determined from the vibrational spectrum by extrapolating the vibrational spacings to:
23. In an anharmonic oscillator, the energy difference between adjacent vibrational levels:
24. The vibrational Raman spectrum typically shows transitions where the selection rule is approximately:
25. Which type of spectroscopy is most commonly used to obtain information about vibrational energy levels and molecular constants?
26. The rotational constant (Be) is related to the equilibrium moment of inertia (Ie) by:
27. The term 'molecular constants' evaluated from vibrational spectral data typically include:
28. The vibrational energy levels of a diatomic molecule, considering anharmonicity, are often expressed by the formula:
29. The anharmonicity constant (αe) in the vibrational energy level expression accounts for:
30. The fundamental vibrational frequency (v=0 to v=1 transition) of a diatomic molecule is often denoted as:
31. The vibrational frequency (ν) of a diatomic molecule is related to its force constant (k) and reduced mass (μ) by which equation?
32. The evaluation of molecular constants from vibrational spectral data typically involves analyzing:
33. Hund's case (d) is a limiting case that applies when:
34. In Hund's case (c), the quantum number Ω represents:
35. Hund's case (c) is characterized by strong spin-orbit coupling, where the electronic orbital and spin angular momenta couple first to form:
36. In Hund's case (b), the electronic orbital angular momentum (Λ) couples primarily to:
37. Hund's case (b) is typically observed in molecules with:
38. In Hund's case (a), the electronic orbital angular momentum vector (Λ) is strongly coupled to:
39. Which Hund's coupling scheme applies to molecules with small spin-orbit coupling, where the electronic orbital angular momentum (Λ) couples to the molecular axis before coupling to the electronic spin (Σ)?
40. What does Hund's coupling scheme describe in diatomic molecules?
41. In a potential energy diagram for electronic transitions, the Franck-Condon principle relates the intensity of a vibronic transition to the overlap between:
42. The intensity distribution among the vibrational peaks within an electronic band system is a direct consequence of:
43. If an electronic transition leads to a significant change in the equilibrium internuclear distance, which vibrational transitions are likely to have the highest probability?
44. Which type of vibrational transitions are most probable according to the Franck-Condon principle, assuming the equilibrium internuclear distance does not change significantly upon electronic excitation?
45. In the context of the Franck-Condon principle, what is assumed about the nuclear positions and momenta during an electronic transition?
46. According to the Franck-Condon principle, electronic transitions are considered:
47. What does the Franck-Condon principle primarily describe in molecular spectroscopy?