A series of lanthanide selenidogermanates, (H(2)peha)[Ln(2)(mu-OH)(2)(tepa)(2)Cl-2]{[Ln(2)(mu-OH)(2)(tepa)(2)Cl](2)(mu-Ge2Se6)}[Ge2Se6] Cl-2 [Ln = Y (1a) and Er (1b); peha = pentaethylenexamine, tepa = tetraethylenepentamine], [Sm-2(mu-OH)(2)(tepa)(2)(mu-Ge2Se6)](n), (2), [Ho-2(mu-OH)(2)(tepa)(2)(mu-Ge2Se6)](n) (3), and [Ce-4(tepa)(4)(mu-GeSe4)(mu-GeSe5)(mu-Ge2Se6)](n) (4), were made under solvothermal conditions. Compounds 1a and 1b contain a protonated H(2)peha(2+) ion, the complex cation [Ln(2)(mu-OH)(2)(tepa)(2)Cl-2](2+), a [Ge2Se6](4-) anion, free Cl- ions, and a {[Ln(2)(mu-OH)(2)(tepa)(2)Cl](2)(mu-Ge2Se6)}(2+) cation constructed by two unsaturated [Ln(2)(mu-OH)(2)(tepa)(2)Cl](3+) groups connecting via the trans terminal Se atoms of the [Ge2Se6](4-) anion, which provides the first example of an organic decorated lanthanide selenidogermanate cation. Both compounds 2 and 3 contain one-dimensional chains [Ln(2)(mu-OH)(2)(tepa)(2)(mu-Ge2Se6)](n) constructed by a combination of unsaturated complex cations [Ln(2)(mu-OH)(2)(tepa)(2)](4+) and [Ge2Se6](4-) anions, but their stacking patterns of neutral chains are different. Compound 4 contains one-dimensional chain [Ce-4(tepa)(4)(mu-GeSe4)(mu-GeSe5)(mu-Ge2Se6)](n), where three different selenidogermanate units acting as bridging ligands connect unsaturated [Ce(tepa)](3+) ions. Compound 4 represents the first example of the coexistence of three different selenidogermanate anions in the same architecture. Their optical properties are studied, and the magnetic properties of compounds 1b and 2-4 are also investigated.