The new series of dileadtrichalcogenide anions Pb2SnSe3-n2- and Pb2SnTe3-n2- (n = 0-3) and Pb2SSeTe2- have been obtained by extraction of the appropriate quaternary or quinternary alloys of the type KPb(x)S(y)Ch(z) (Ch = Se, Te, or Se/Te) in ethylenediamine ten) and characterized in en solution by Se-77, Te-125, and Pb-207 NMR spectroscopy. The NMR findings indicate that the solution structures of the anions are based on a trigonal bipyramid having axial lead atoms bonded to three chalcogen atoms in the equatorial plane. Direct and pairwise additivity trends among the Pb(2)S(n)Ch(3-n)(2-) (Ch = Se or Te) series show that (1)J((Pb-77Se)-Pb-207), delta(Pb-207), delta(Se-77), and delta(Te-125) decrease upon chalcogen atom substitution as follows : S --> Te > Se --> Te >> S --> Se, The isostructural Sn2Se32- and SnPbSe32- anions have also been prepared in en by reaction of K2Se with SnSe and SnSe/PbSe mixtures, respectively, and represent the first examples of Sn(II) chalcogenide anions. Both anions were characterized in en solution by Se-77, Sn-117, Sn-119, and Pb-207 NMR spectroscopy. The two-bond Sn(II)-Sn(II) and Sn(II)-Pb(II) coupling constants, (2)J(Sn-117-Sn-119) and (2)J(Sn-119-Pb-207), have been observed for the first time and represent unusually large values [i.e., (2)J(Sn-119-Sn-117) = 1514 Hz and (2)J(Sn-119-Pb-207) = 1145 Hz]. After removal of the nuclear dependence to give reduced coupling constants, K-1(M-Ch), and after allowances for relativistic effects, which are significant in the heavy-element spin-spin couplings being considered, the magnitudes of the relativistically corrected reduced couplings, (K-1(M-Ch))(RC), of the tin, lead, and tin/lead trigonal bipyramidal cage anions are shown to be consistent with predominantly p-bonded cages. The syntheses and crystal structures are reported for two salts in which the Sn2Te32- and Sn2Se32- anions have been stabilized as a result of complexation of the potassium cations by 4,7,13,16,21,24-hexaoxa-1,-10-diazabicyclo[8.8.8]hexacosane (2,2,2-crypt). The crystal structure of (2,2,2-crypt-K+)(2)Sn2Te32- was determined at -100 and 24 degrees C; it crystallizes in the trigonal system P (3) over bar c1, with two molecules in a unit cell of dimensions a = 11.703(4) [11.817(9)] Angstrom and c = 21.945(6) [22.01(2)] Angstrom at -100 degrees C [24 degrees C] with R = 0.0628 [0.102] for 757 [305] observed (I > 2[2]sigma(I)) reflections. : S --> Te > Se --> Te >> S --> Se, The isostructural Sn2Se32- and SnPbSe32- anions have also been prepared in en by reaction of K2Se with SnSe and SnSe/PbSe mixtures, respectively, and represent the first examples of Sn(II) chalcogenide anions. Both anions were characterized in en solution by Se-77, Sn-117, Sn-119, and Pb-207 NMR spectroscopy. The two-bond Sn(II)-Sn(II) and Sn(II)-Pb(II) coupling constants, (2)J(Sn-117-Sn-119) and (2)J(Sn-119-Pb-207), have been observed for the first time and represent unusually large values [i.e., (2)J(Sn-119-Sn-117) = 1514 Hz and (2)J(Sn-119-Pb-207) = 1145 Hz]. After removal of the nuclear dependence to give reduced coupling constants, K-1(M-Ch), and after allowances for relativistic effects, which are significant in the heavy-element spin-spin couplings being considered, the magnitudes of the relativistically corrected reduced couplings, (K-1(M-Ch))(RC), of the tin, lead, and tin/lead trigonal bipyramidal cage anions are shown to be consistent with predominantly p-bonded cages. The syntheses and crystal structures are reported for two salts in which the Sn2Te32- and Sn2Se32- anions have been stabilized as a result of complexation of the potassium cations by 4,7,13,16,21,24-hexaoxa-1,-10-diazabicyclo[8.8.8]hexacosane (2,2,2-crypt). The crystal structure of (2,2,2-crypt-K+)(2)Sn2Te32- was determined at -100 and 24 degrees C; it crystallizes in the trigonal system P (3) over bar c1, with two molecules in a unit cell of dimensions a = 11.703(4) [11.817(9)] Angstrom and c = 21.945(6) [22.01(2)] Angstrom at -100 degrees C [24 degrees C] with R = 0.0628 [0.102] for 757 [305] observed (I > 2[2]sigma(I)) reflections.