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Cs[Tf₂N]: a second polymorph with a layered structure.

ABSTRACT: The structural determination of the ionic liquid, caesium bis-[(tri-fluoro-meth-yl)sulfon-yl]imide or poly[[μ₄-bis-[(tri-fluoro-meth-yl)sulfon-yl]imido]caesium(I)], Cs[N(SO₂CF₃)₂] or Cs[Tf₂N], reveals a second polymorph that also crystallizes in a layer structure possessing monoclinic P2₁/c symmetry at 120 K instead of C2/c for the known polymorph [Xue et al. (2002 ▸). Solid State Sci.4, 1535-1545]. The caesium ions in the cationic layers are coordinated by the sulfonyl groups of the bis-triflimide mol-ecules from anion layers while the tri-fluoro-methyl groups are oriented in the opposite direction, forming a non-polar surface separating the layers. The layer direction is (100).

SUBMITTER: Stritzinger JT

PROVIDER: S-EPMC5946987 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Cs[Tf2N]: a second polymorph with a layered structure.

Stritzinger Jared T JT Droessler Janelle E JE Scott Brian L BL Goff George S GS

Acta crystallographica. Section E, Crystallographic communications 20180323 Pt 4

The structural determination of the ionic liquid, caesium bis-[(tri-fluoro-meth-yl)sulfon-yl]imide or poly[[μ4-bis-[(tri-fluoro-meth-yl)sulfon-yl]imido]caesium(I)], Cs[N(SO2CF3)2] or Cs[Tf2N], reveals a second polymorph that also crystallizes in a layer structure possessing monoclinic P21/c symmetry at 120 K instead of C2/c for the known polymorph [Xue et al. (2002 ▸). Solid State Sci.4 ...[more]

PMID: 29765765

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