Aromatic, conjugated and polymeric species of Sn in the solid state.

Recent advances in tetrel chemistry (Tt = Si, Ge, Sn, Pb), stimulated the search for other Zintl phases with novel anionic structures. For that reason, we began thorough and systematic studies over the pseudobinary A–AE–Tt systems (A = alkali metal; AE = alkaline-earth). After exploring a great deal of compositions within the pseudo-binary systems with mixed A/AE metals, we have embarked on exploring analogous systems with the help of mixed of alkali and rare-earth metals (RE). The major part of the work presented in this dissertation deals with the synthesis and structural characterization of a variety of novel intermetallic compounds. A few noteworthy examples are: 1) Na8BaSn6 and Na8BaPb6 with aromatic pentagonal rings of Sn56- and Pb56-, respectively, that are isostructural and isoelectronic with the cyclpentadienyl anion, C5H5 -; 2) Li9-xEuSn6+x, Li5Ca7Sn11, L i6Eu5Sn9 with trimers, hexamers and infinite conjugated chains of Sn, in addition to aromatic pentagonal rings; 3) LiMgEu2Sn3 and LiMgSr2Sn3 with infinite conjugated chains of Sn and single atom anions; 4) Na4CaSn6 with channels built of cyclohexane-like units of Sn6 6-; 5)Li2Ln5Sn7 (Ln = Ce, Pr, Sm, Eu) with branched polymeric 1D chains. Another part of this dissertation concentrates on our attempts to synthesize heteroatomic rings isoelectronic with those of group 14 by a combination of elements from groups 13 (Tr) and 15 (Pn), respectively. However all probed reactions produced novel compounds with extended structures based on TrPn4-tetrahedra. All of the above-mentioned compounds nicely illustrate the delicate balance between packing efficiency and electronic requirements, which explains the stabilization of these novel tetrel clusters, which are inaccessible in pure binary systems.