A Combination of X-ray Single-Crystal Diffraction and Monte Carlo Structure Solution from X-ray Powder Diffraction Data in a Structural Investigation of 5-Bromonicotinic Acid and Solvates Thereof

The crystal structures of 5-bromonicotinic acid ethylacetate 1, 5-bromonicotinic acid acetonitrile 2,
and 5-bromonicotinic acid methanol 3 (all of which were obtained from single-crystal data) and of 5-bromonicotinic
acid 4 (solved from powder diffraction data using a direct-space method based on the Monte Carlo technique) are
presented; in 1−3, heteromeric N-H···O/C-H···O hydrogen-bonds lead to infinite polar chains of 5-bromonicotinic
acid, whereas in 4, the principal noncovalent connector (head-to-head acid···acid hydrogen bonds) generates
centrosymmetric dimers.