| Summary: | Although the electronic structures of several tellurides have been recognized by applying the <i>Zintl</i>-<i>Klemm</i> concept, there are also tellurides whose electronic structures cannot be understood by applications of the aforementioned idea. To probe the appropriateness of the valence-electron transfers as implied by <i>Zintl</i>-<i>Klemm</i> treatments of ALn<sub>2</sub>Ag<sub>3</sub>Te<sub>5</sub>-type tellurides (A = alkaline-metal; Ln = lanthanide), the electronic structure and, furthermore, the bonding situation was prototypically explored for RbPr<sub>2</sub>Ag<sub>3</sub>Te<sub>5</sub>. The crystal structure of that type of telluride is discussed for the examples of RbLn<sub>2</sub>Ag<sub>3</sub>Te<sub>5</sub> (Ln = Pr, Nd), and it is composed of tunnels which are assembled by the tellurium atoms and enclose the rubidium, lanthanide, and silver atoms, respectively. Even though a <i>Zintl</i>-<i>Klemm</i> treatment of RbPr<sub>2</sub>Ag<sub>3</sub>Te<sub>5</sub> results in an (electron-precise) valence-electron distribution of (Rb<sup>+</sup>)(Pr<sup>3+</sup>)<sub>2</sub>(Ag<sup>+</sup>)<sub>3</sub>(Te<sup>2−</sup>)<sub>5</sub>, the bonding analysis based on quantum-chemical means indicates that a full electron transfer as suggested by the <i>Zintl</i>-<i>Klemm</i> approach should be considered with concern.
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