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Bottom energy level

Figure Al.2.12. Energy level pattern of a polyad with resonant collective modes. The top and bottom energy levels conespond to overtone motion along the two modes shown in figure Al.2.11. which have a different frequency. The spacing between adjacent levels decreases until it reaches a minimum between the third and fourth levels from the top. This minimum is the hallmark of a separatrix [29, 45] in phase space. Figure Al.2.12. Energy level pattern of a polyad with resonant collective modes. The top and bottom energy levels conespond to overtone motion along the two modes shown in figure Al.2.11. which have a different frequency. The spacing between adjacent levels decreases until it reaches a minimum between the third and fourth levels from the top. This minimum is the hallmark of a separatrix [29, 45] in phase space.
Figure Bl.16.14. Top, the canonical axes for triplet naphthalene. The z-axis is directed out of the plane of the paper. Bottom, energy levels and relative populations during the CIDEP triplet mechanism process. See text... Figure Bl.16.14. Top, the canonical axes for triplet naphthalene. The z-axis is directed out of the plane of the paper. Bottom, energy levels and relative populations during the CIDEP triplet mechanism process. See text...
The electronic or energetic factors in catalysis, such as electronic theory that is mainly used for studying solid physics, including finding a link between catalysis and the bottom energy level, conductivity, work function and d-electron character etc, and considering the difhculty of formation of ionic state species from reactant molecules on the surface of a solid. [Pg.70]

Figure Bl.2.3. Comparison of the hannonic oscillator potential energy curve and energy levels (dashed lines) with those for an anliannonic oscillator. The hannonic oscillator is a fair representation of the tnie potential energy curve at the bottom of the well. Note that the energy levels become closer together with increasing vibrational energy for the anliannonic oscillator. The aidiannonicity has been greatly exaggerated. Figure Bl.2.3. Comparison of the hannonic oscillator potential energy curve and energy levels (dashed lines) with those for an anliannonic oscillator. The hannonic oscillator is a fair representation of the tnie potential energy curve at the bottom of the well. Note that the energy levels become closer together with increasing vibrational energy for the anliannonic oscillator. The aidiannonicity has been greatly exaggerated.
Figure Bl.15.8. (A) Left side energy levels for an electron spin coupled to one nuclear spin in a magnetic field, S= I =, gj >0, a<0, and a l 2h)<(a. Right side schematic representation of the four energy levels with )= Mg= , Mj= ). +-)=1, ++)=2, -)=3 and -+)=4. The possible relaxation paths are characterized by the respective relaxation rates W. The energy levels are separated horizontally to distinguish between the two electron spin transitions. Bottom ENDOR spectra shown when a /(21j)< ca (B) and when co < a /(2fj) (C). Figure Bl.15.8. (A) Left side energy levels for an electron spin coupled to one nuclear spin in a magnetic field, S= I =, gj >0, a<0, and a l 2h)<(a. Right side schematic representation of the four energy levels with )= Mg= , Mj= ). +-)=1, ++)=2, -)=3 and -+)=4. The possible relaxation paths are characterized by the respective relaxation rates W. The energy levels are separated horizontally to distinguish between the two electron spin transitions. Bottom ENDOR spectra shown when a /(21j)< ca (B) and when co < a /(2fj) (C).
Figure Bl.15.12. ESEEM spectroscopy. (A) Top energy level diagram and the corresponding stick spectrum for the two allowed (a) and two forbidden (f) transitions. Bottom time behaviour of the magnetization of an allowed (a) spin packet and a forbidden (f) spin packet during a two-pulse ESE sequence (see figure Bl.15.11 (A)). (B) The HYSCORE pulse sequence. Figure Bl.15.12. ESEEM spectroscopy. (A) Top energy level diagram and the corresponding stick spectrum for the two allowed (a) and two forbidden (f) transitions. Bottom time behaviour of the magnetization of an allowed (a) spin packet and a forbidden (f) spin packet during a two-pulse ESE sequence (see figure Bl.15.11 (A)). (B) The HYSCORE pulse sequence.
Figure Bl.15.13. Pulsed ENDOR spectroscopy. (A) Top energy level diagram of an. S-/=i spin system (see also figure Bl,15,8(A)). The size of the filled circles represents the relative population of the four levels at different times during the (3+1) Davies ENDOR sequence (bottom). (B) The Mims ENDOR sequence. Figure Bl.15.13. Pulsed ENDOR spectroscopy. (A) Top energy level diagram of an. S-/=i spin system (see also figure Bl,15,8(A)). The size of the filled circles represents the relative population of the four levels at different times during the (3+1) Davies ENDOR sequence (bottom). (B) The Mims ENDOR sequence.
These absorptions are ascribed to n-n transitions, that is, transitions of an electron from the highest occupied n molecular orbital (HOMO) to the lowest unoccupied n molecular orbital (LUMO). One can decide which orbitals are the HOMO and LUMO by filling electrons into the molecular energy level diagram from the bottom up, two electrons to each molecular orbital. The number of electrons is the number of sp carbon atoms contributing to the n system of a neuhal polyalkene, two for each double bond. In ethylene, there is only one occupied MO and one unoccupied MO. The occupied orbital in ethylene is p below the energy level represented by ot, and the unoccupied orbital is p above it. The separation between the only possibilities for the HOMO and LUMO is 2.00p. [Pg.197]

Figure 23. This caricature demonstrates the predicted phenomena of energy level crossing in domains whose energy bias is comparable or larger than the vibronic frequency of the domain wall distortions. The vertical axis is the energy measured from the bottom state the horizontal axis denotes temperature. The diagonal da ed line denotes roughly the thermal energies. A tunneling center that would become thermally active at some temperature Tq will not possess ripplons whose frequency is less than To. Figure 23. This caricature demonstrates the predicted phenomena of energy level crossing in domains whose energy bias is comparable or larger than the vibronic frequency of the domain wall distortions. The vertical axis is the energy measured from the bottom state the horizontal axis denotes temperature. The diagonal da ed line denotes roughly the thermal energies. A tunneling center that would become thermally active at some temperature Tq will not possess ripplons whose frequency is less than To.
The chemisorbed reaction product can be characterized by more shallow positioning of the energy level with respect to the bottom of conductivity band if contrasted to Z (A ) which results in emission of electron into the conductivity band in compliance with reaction... [Pg.144]

Fig. 5.2 Radial distribution curves, Pv Fig. 5.2 Radial distribution curves, Pv <v(r) 2/r for different vibrational states of carbon monosulfide, C = S, calcualted2 for Boltzmann distributions, with pv = exp(—EJkT), at T = 1000K (top) and T = 5000K (bottom) arbitrarily selected for the sake of illustration, where Ev is the energy level of state v. The figure conveys an impression of how state-average distance values, which can be derived from experimental spectroscopic data, differ from distribution-average values, derived from electron diffraction data for an ensemble of molecules at a given vibrational temperature. Both observables in turn differ from the unobservable stateless equilibrium distances which are temperature-independent in the Born-Oppenheimer approximation.
The procedure of Frost and Musulin can be adapted to chain systems with it bonding in the following way. For a chain having m atoms, draw a polygon as before, except it must have m + 2 sides. Disregard the top and bottom vertices and use only one side of the polygon where it makes contact with the circle to determine the energy levels. [Pg.171]


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See also in sourсe #XX -- [ Pg.70 ]




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