Energy level diagrams Tanabe-Sugano

Figure 2 A semiquantitative energy level diagram (Tanabe-Sugano diagram) for the d5 configuration2...

Figure 6.8 The Sugano-Tanabe diagram of a 3d electronic configuration (C/5 = 4.5). The two vertical lines correspond to the DqlB values in the crossover and for the ruby crystal (see the text). The inset shows the energy-level diagram for strong crystal fields.

Figure 9.5 Energy level diagrams [after Tanabe and Sugano, J. Phys. Soc. Jpn., 9, 753 (1954)] for the d2-d configurations, in octahedral symmetry. Note For dh this is the correct diagram—not the incorrect one often encountered [A. C. Hormann and C. F. Shaw. J. Chem. Educ64, 918 (1987)].

Figure 3.8 Tanabe-Sugano energy level diagram for a 3d6 ion in an octahedral crystal field. Note that some of the highest energy triplet and singlet crystal field states listed in table 3.3 are not shown in the diagram.

Comparable energy level diagrams to that shown for Fe2+ in fig. 3.8 may be constructed for each transition metal cation from spectroscopic terms of the field-free ion. The Tanabe-Sugano diagrams for other octahedrally coordinated transition metal ions are discussed later in chapter 5 ( 5.10)... 

Figure 5.23 Tanabe-Sugano energy level diagram for V3+, 3d2, in octahedral coordination calculated from spectral data for V3+-doped corundum. Transitions in V3+in A1203 are shown by the dashed line.

Yukito Tanabe and Satom Sugano Calculation of energy level diagrams for octahedral d-group complexes... 

Consider the comparison between the two ions, Mo + and Re +. Figure 18 presents the relevant portion of a Tanabe-Sugano energy-level diagram for octahedral d ions. Luminescence is observed from both the first ( Tj/ E, NIR) and second ( T2, red) excited-state multiplets in both ions [69,70]. In Mo +, excitation into the higher-energy, broader, and more intense T2 and interconfigu-rational d-d transitions leads to rapid relaxation followed by red A2 lumi-... 

Fig. 18. Tanabe-Sugano energy-level diagram (using parameters from Mo C/B = 3.7, B = 487 [81]. Up arrows indicate two-photon excitation processes observed in Mo + and Re. Down arrows indicate the upconversion luminescence used to monitor these processes. Adapted from [68]...

Fig. 4. Energy level diagram for the d configuration in octahedral symmetry. (Adapted from Tanabe and Sugano. )...

Another important detail on the Sugano-Tanabe diagram shown in Figure 6.8 is the vertical line at the value DqlB = 2.2, at which the states T2g and E are equal in energy. This value of DqlB is usually referred to as the crossover value. Materials (crystal - - ion) for which Dq/B is less than the crossover value are usually called low crystal field materials. Eor these materials, the lowest energy level is the " T2g and so they present a characteristic broad and intense emission band associated with the spin-allowed T2g A2g transition (which is usually a vibronic transition). On the other hand, the materials on the right-hand side of the crossover line are called high crystal field materials. These materials (such as the ruby crystal) present a narrow-line emission related to the spin-forbidden Eg A2g transition, usually called R-line emission. 

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