title: Isotopomeric polymorphism.
abstract: The complex formed between 4-methylpyridine and pentachlorophenol (4MPPCP) crystallizes in a triclinic space group. If the same complex is synthesized from deuterated pentachlorophenol (4MPPCP-d1), it crystallizes in an entirely different monoclinic polymorph. Solid-state NMR of samples synthesized with a full range of deuteration levels, crystallized from solution or the melt, and in the presence or absence of seeds confirms that the isotopomers indeed have different thermodynamically stable crystal structures. The phenomenon is apparently due to very different hydrogen bond strengths between the two polymorphs.
authors.affiliation: Department of Chemistry, University of Nebraska at Lincoln, Lincoln, Nebraska 68588, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Young-Sik
authors.initials: YS
authors.lastname: Kye
authors.forename: Gerard S
authors.initials: GS
authors.lastname: Harbison
mesh_terms: D003903:Deuterium; D006860:Hydrogen Bonding; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D010416:Pentachlorophenol / Q000031:analogs & derivatives* / Q000737:chemistry; D011725:Pyridines / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D011725:Pyridines; D003903:Deuterium; D010416:Pentachlorophenol