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The orthorhombic polymorph of pyrazine-2-carboxylic acid revisited

✍ Scribed by Małecki, Jan Grzegorz ;Kruszynski, Rafal ;Kusz, Joachim

Publisher: International Union of Crystallography
Year: 2007
Tongue: English
Weight: 782 KB
Volume: 63
Category: Article
ISSN: 1600-5368
DOI: 10.1107/s1600536807030036

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✦ Synopsis

The crystal structure of the orthorhombic polymorph of the title compound, C 5 H 4 N 2 O 2 , was previously reported in the space group Pna2 1 [Takusagawa, Higuchi, Shimada, Tamura & Sasada (1974). Bull. Chem. Soc. Jpn, 47, 1409Jpn, 47, -1413]]. Redetermination of this structure shows that the space group is centrosymmetric, Pnma, with the molecule located at a special position of m symmetry. The molecules are joined via O-HÁ Á ÁN hydrogen bonds into a chain and further via C-HÁ Á ÁO interactions into a sheet parallel to (010). No face-toface stacking interactions are observed in this polymorph.

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