April 2011 issue
Cover illustration: In this compound, C7H10N+·ClO4-·C20H24O6, the protonated benzylamine cation forms a rotator-stator complex with the 18-crown-6 (1,4,7,10,13,16-hexaoxacyclooctadecane) molecule via three bifurcated hydrogen N-HO hydrogen bonds each to two adjacent oxygen atoms of the crown ring. The complex cations form chains parallel to  via weak C-H interactions parallel to , with the perchlorate anions located between the chains. See Wang, Li & Wang [Acta Cryst. (2011). E67, o772].