title: trans-4-Bromo-ONN-azoxybenzene at 100 K.
abstract: The crystal structure of the alpha isomer of trans-4-bromoazoxybenzene [systematic name: trans-1-(bromophenyl)-2-phenyldiazene 2-oxide], C(12)H(9)BrN(2)O, has been determined by X-ray diffraction. The geometries of the two molecules in the asymmetric unit are slightly different and are within approximately 0.02 A for bond lengths, approximately 2 degrees for angles and approximately 3 degrees for torsion angles. The azoxy bridges in both molecules have the typical geometry observed for trans-azoxybenzenes. The crystal network contains two types of planar molecules arranged in columns. The torsion angles along the Ar-N bonds are only 7 (2) degrees, on either side of the azoxy group.
authors.affiliation: Institute of Chemistry, University of Opole, Oleska 48, 45-052 Opole, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Ejsmont
authors.forename: Andrzej A
authors.initials: AA
authors.lastname: Domański
authors.forename: Janusz B
authors.initials: JB
authors.lastname: Kyzioł
authors.forename: Jacek
authors.initials: J
authors.lastname: Zaleski