title: Ionic disparity of identical molecules in polymorphs.
abstract: [structure: see text] Formation of ionic pairs of identical molecules, extremely common in Nature but exceptional for diffractometric observations in the crystalline state, has been found in one of two polymorphs of a nucleobase analogue, 4,6-pyrimidinedione (1). The occurrence of the neutral and ionic polymorphs of 1 in many respects resembles neutral-ionic transitions of electon-donor/acceptor complexes. The ionization affects the reactivity of 1 and illustrates general properties of H-tautomers with low-disproportionation energy.
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland. katran@amu.edu.pl
authors.forename: Andrzej
authors.initials: A
authors.lastname: Katrusiak
authors.forename: Anna
authors.initials: A
authors.lastname: Katrusiak