Studies on polyhalides. 41. On ethylmethyldiphenylammoniumpolyiodides (EtMePh2N)I-x with x = 3,5: Preparation and crystal structures of a triiodide (EtMePh2N)I-3 and a pentaiodide (EtMePh2N)I-5

So far unknown compounds (EtMePh2N)I-x with x=3 and 5 have been prepared an d structurally characterized. The triiodide (EtMePh2N)I-3 crystallizes monoclinically in C2/c with a = 34 06.1(3) pm, b = 893.1(1) pm, c = 1222.7(1) pm, beta= 99.24(1)degrees and Z = 8. The crystal structure contains cationic and two kinds of anionic layer s alternating along [1 0 0]. One anionic layer is composed of triiodide ion s forming the typical and widespread observed herring-bone pattern. The oth er one contains zigzag chains (1)(infinity)(I- . I-2) along [0 0 1] as a so far not observed structural motif. The pentaiodide (EtMePh2N)I-5 crystallizes triclinically in P (1) over bar with a=1020.7(1) pm, b=1023.1(1) pm, c=1269.5(1) pm, alpha= 81.88(1)degrees , beta= 72.66(1)degrees, gamma = 60.65(1)degrees and Z = 2. The crystal str ucture is divided into along [0 1 1] alternating puckered cationic and anio nic layers. The anions have the common shape of a V, but are here of the ra re isolated type. From a topological view two pentaiodide ions are connecte d to chairlike decagonal rings which are concatenated along [0 (1) over bar 1].