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Ionothermal Synthesis, Structure, and Bonding of the Catena ‐Heteropolycation 1 ∞ [Sb 2 Se 2 ] +
Author(s) -
Groh Matthias F.,
Breternitz Joachim,
Ahmed Ejaz,
Isaeva Anna,
Efimova Anastasia,
Schmidt Peer,
Ruck Michael
Publication year - 2015
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/zaac.201400543
Subject(s) - crystallography , triclinic crystal system , chemistry , antimony , crystal structure , selenium , covalent bond , inorganic chemistry , organic chemistry
The reaction of antimony and selenium in the Lewis‐acidic ionic liquid 1‐butyl‐3‐methyl‐imidazolium tetrachloridoaluminate, [BMIm]Cl · 4.7AlCl 3 , yielded dark‐red crystals of [Sb 2 Se 2 ]AlCl 4 . The formation starts above 160 °C; at about 190 °C, irreversible decomposition takes place. The compound crystallizes in the triclinic space group P $\bar{1}$ with a = 919.39(2) pm, b = 1137.92(3) pm, c = 1152.30(3) pm, α = 68.047(1)°, β = 78.115(1)°, γ = 72.530(1)°, and Z = 4. The structure is similar to that of [Sb 2 Te 2 ]AlCl 4 but has only half the number of crystallographically independent atoms. Polycationic chains 1 ∞ [Sb 2 Se 2 ] + form a pseudo‐hexagonal arrangement along [011 $\bar{}$ ], which is interlaced by tetrahedral AlCl 4 – groups. The catena ‐heteropolycation 1 ∞ [Sb 2 Se 2 ] + is a sequence of three different four‐membered [Sb 2 Se 2 ] rings. The chemical bonding scheme, established from the topological analysis of the real‐space bonding indicator ELI‐D, includes significantly polar covalent bonding in four‐member rings within the polycation. The rings are connected into an infinite chain by homonuclear non‐polar Sb–Sb bonds and highly polar Sb–Se bonds. Half of the selenium atoms are three‐bonded.