Heterometallic chalcogenolate compounds containing both lanthanide (Ln) and group 14 metals (M; M = Sn, Pb) form a variety of structures that can be understood in the context of relative metal-chalcogen bond strengths. The compounds (THF)(2)Eu(mu(2)-SePh)(6)Pb-2 (1), [Yb(THF)(6)][Sn(SePh)(3)](2) (2), and [(py)(2)Eu(2-S-NC5H4)(2)Sn(2-S-NC5H4)(2)](n) (3) have been prepared, and their structures have been established by low-temperature single-crystal X-ray diffraction. Ln-S bonds are found to be relatively insensitive to the presence of a group 14 metal thiolate, whereas Ln-Se bonds are readily distorted upon coordination to Pb(SePh)(2), and cleaved by the addition of the stronger Lewis acid Sn(SePh)(2). The stereochemically active lone pair of electrons on the group 14 metal influences structure, as does the identity of the chalcogenolate. All three compounds show no interaction between the Ln ion and the group 14 metal lone pair. Crystal data (1-3 Mo K alpha; -80 to -100 degrees C): 1, triclinic space group P (1) over bar, a = 10.582(3) Angstrom, b = 12.114(2) Angstrom, c = 18.946(6) Angstrom, alpha = 89.57(2)degrees, beta = 86.11(4)degrees, gamma = 75.87(2)degrees V = 2350(1) Angstrom(3), Z = 2; 2, monoclinic space group P2(1)/c, a = 12.961(2) Angstrom, b = 22.768(4) Angstrom, c = 22.560(4) Angstrom, beta = 95.04(2)degrees, V = 6632(2) Angstrom(3), Z = 4; 3, monoclinic space group Cc, a = 20.737(6) Angstrom, b = 9.801(3) Angstrom, c = 18.849(5) Angstrom, beta = 125.34(2)degrees, V = 3125(2) Angstrom(3), Z = 4.