title: Low-temperature phase transition in glycine-glutaric acid co-crystals studied by single-crystal X-ray diffraction, Raman spectroscopy and differential scanning calorimetry.
abstract: The occurrence of a first-order reversible phase transition in glycine-glutaric acid co-crystals at 220-230 K has been confirmed by three different techniques - single-crystal X-ray diffraction, polarized Raman spectroscopy and differential scanning calorimetry. The most interesting feature of this phase transition is that every second glutaric acid molecule changes its conformation, and this fact results in the space-group symmetry change from P2(1)/c to P1. The topology of the hydrogen-bonded motifs remains almost the same and hydrogen bonds do not switch to other atoms, although the hydrogen bond lengths do change and some of the bonds become inequivalent.
authors.affiliation: Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk, Russian Federation. b.zakharov@yahoo.com
authors.forename: Boris A
authors.initials: BA
authors.lastname: Zakharov
authors.forename: Evgeniy A
authors.initials: EA
authors.lastname: Losev
authors.forename: Boris A
authors.initials: BA
authors.lastname: Kolesov
authors.forename: Valeri A
authors.initials: VA
authors.lastname: Drebushchak
authors.forename: Elena V
authors.initials: EV
authors.lastname: Boldyreva
mesh_terms: D002152:Calorimetry, Differential Scanning; D003080:Cold Temperature; D003460:Crystallization; D018360:Crystallography, X-Ray; D005977:Glutarates / Q000737:chemistry*; D005998:Glycine / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D044367:Phase Transition; D013059:Spectrum Analysis, Raman
chemical_list: D005977:Glutarates; C035736:glutaric acid; D005998:Glycine