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1700485 
Journal Article 
Penta-, Hepta-, and Octaiodide Anions in Salts with Alkaline Earth Metal Crown Ether Cations 
Walbaum, C; Pantenburg, I; Meyer, G 
2010 
1 
Zeitschrift für Naturforschung B
ISSN: 0932-0776 
65 
9 
1077-1083 
WOS:000284300500004 
Salts of alkaline earth metal cations sequestered in dibenzo 18-crown-6 (Db18c6) and benzo-15-crown-5 (B15c5) respectively with I-5(-) I-7(-) and I-8(2-) as the anions have been synthesized and their crystal structures determined by single-crystal X-ray diffraction [Ca(Db18c6)(H2O)(3)](I-5)(2) (Db18c6)(H2O) (1) monoclinic P2(1) (no 4) a = 1322 1(2) b = 1849 1(2) c = 1344 0(2) pm beta = 114 70(1)degrees V = 2985 2(6) x 10(6) pm(3) Z = 2 [Sr(B15c5)(2)](I-7)(2) (2) triclinic P (1) over bar (no 2) a = 973 9(5) b = 1244 0(5) c = 1293 3(5) pm, alpha = 115 28(1), beta = 90 18(1) gamma = 104 57( 1)degrees V = 1360 2(10) x 10(6) pm(3) Z = 2 [Ba(Db18c6)(2)]I-8 (3) orthorhombic, Pbcn (no 60) a = 1452 0(2) b = 1924 6(2) c = 1912 1(2) pm, V = 5343 3(10) x 10(6) pm(3) Z = 4 Compound 1 contains two crystallographically independent V-shaped pentaiodide anions I-5(-) which are linked to dimers by weak interionic contacts The unusual heptaiodide anion I-7(-) in 2 can be described as a V shaped pentaiodide unit, which is connected to a slightly widened iodine molecule to give the rare Z form Secondary bonding distances lead to almost planar ten-membered iodine rings which are connected through common edges to form ribbons with staircase like folding 3 is built of sandwich-like cations and centrosymmetric octaiodide anions I-8(2-) An inspection for secondary contacts reveals that the iodine substructure of 3 consists of essentially isolated octaiodide units 
Pentaiodide; Heptaiodide; Octaiodide; Crown Ether; Crystal Structure