@article { , title = {Polymorphism and solid−gas/solid−solid reactions of isonicotinic acid, isonicotinamide, and nicotinamide copper chloride compounds}, abstract = {The crystal structures of eight new copper chloride coordination complexes with substituted pyridines have been determined through a combination of single crystal X-ray diffraction and ab initio structure solution from X-ray powder diffraction data. The polymeric compounds [CuCl₂(INAc)₂]n (1), [CuCl₂(INAm)₂]n (2), and [CuCl₂(NAm)₂]n (3) (INAc = isonicotinic acid; INAm = isonicotinamide; NAm = nicotinamide) consist of chains of CuCl4 edge-sharing rhombi decorated by the pyridine-based ligands. All three compounds display similar hydrogen bonding interactions but differ in the arrangement of the polymeric chains. 1, 2, and 3 react reversibly with hydrochloric acid in solution/vapor form to produce the corresponding tetrachlorocuprate salts [CuCl₄](H-INAc)₂(H₂O) (4a), [CuCl₄](H-INAc)₂ (4b), [CuCl₄](H-INAm)₂ (form I/form II 5a/5b), and [CuCl₄](H-NAm)₂ (form I/form II 6a/6b). 4a exhibits discrete square planar [CuCl4]₂– ions, whereas the Cu in 4b, 5a, and 5b is in a 4 + 2 coordination. All four compounds display hydrogen bonding arrangements similar to those found in 1 and 2. 6a and 6b differ substantially from these compounds in both the hydrogen bonding contacts and the coordination geometry of the cuprate ion (flattened tetrahedral), though they differ from each other only in the orientation of the amide groups and packing arrangements. The formation of 6a/6b depends on the configuration of nicotinamide in the starting material.}, doi = {10.1021/acs.cgd.6b01295}, eissn = {1528-7505}, issn = {1528-7483}, issue = {1}, journal = {Crystal growth and design}, pages = {106-116}, publicationstatus = {Published}, publisher = {American Chemical Society}, url = {https://hull-repository.worktribe.com/output/445778}, volume = {17}, keyword = {Specialist Research - Other, Polymorphism, Solid-gas/solid-solid reactions, Copper chloride coordination complexes}, year = {2017}, author = {Fellows, Simon M. and Prior, Timothy J.} }