Formamidinium iodide: crystal structure and phase transitions.

ABSTRACT: At a temperature of 100 K, CH₅N₂⁺·I^- (I), crystallizes in the monoclinic space group P2₁/c. The formamidinium cation adopts a planar symmetrical structure [the r.m.s. deviation is 0.002 Å, and the C-N bond lengths are 1.301 (7) and 1.309 (8) Å]. The iodide anion does not lie within the cation plane, but deviates from it by 0.643 (10) Å. The cation and anion of I form a tight ionic pair by a strong N-H⋯I hydrogen bond. In the crystal of I, the tight ionic pairs form hydrogen-bonded zigzag-like chains propagating toward [20-1] via strong N-H⋯I hydrogen bonds. The hydrogen-bonded chains are further packed in stacks along [100]. The thermal behaviour of I was studied by different physicochem

SUBMITTER: Petrov AA 

PROVIDER: S-EPMC5382624 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature