Open AccessThe catena ‐arsenite chain anion, [AsO 2 ] n n − : (H 3 NCH 2 CH 2 NH 3 ) 0.5 [AsO 2 ] and NaAsO 2 (revisited)
Author(s) -
Lee Clare,
Harrison William T. A.
Publication year - 2004
Publication title -
acta crystallographica section c
Language(s) - English
Resource type - Journals
eISSN - 1600-5759
pISSN - 0108-2701
DOI - 10.1107/s0108270104007450
Subject(s) - chemistry , arsenite , crystallography , ion , trigonal crystal system , ammonium , hydrogen bond , atom (system on chip) , octahedron , crystal structure , inorganic chemistry , stereochemistry , molecule , arsenic , organic chemistry , computer science , embedded system
The title compounds contain the catena ‐arsenite [AsO 2 ] n n − unit, in which the As III atom is pyramidally coordinated to one terminal and two bridging O atoms, resulting in an infinite anionic chain. Ethylenediammonium catena ‐arsenite, (C 2 H 10 N 2 ) 0.5 [AsO 2 ], is the first example of this anion in the company of an organic cation. The ethylenediammonium species interact with the [AsO 2 ] − chains by way of N—H⋯O hydrogen bonds. The structure of sodium catena ‐arsenite, Na[AsO 2 ] [Menary (1958). Acta Cryst . 11 , 742–743], has been redetermined to yield more reliable geometrical parameters. The As—O distances are normal and the Na + cation is seven‐coordinate [Na—O = 2.285 (4)–3.063 (4) Å] in a distorted capped trigonal prismatic geometry.