Synthesis and thermal properties of the inorganic–organic transition metal halogenides CuCl–pyrazine and Cu 2Cl 2–pyrazine

Abstract

The coordination polymers CuCl–pyrazine and Cu 2Cl 2–pyrazine were synthesised by the reaction of CuCl with pyrazine in aqueous solution under hydrothermal conditions. Using an excess of pyrazine, phase pure CuCl–pyrazine can be prepared in high yield. On lowering the pyrazine excess only a small amount of Cu 2Cl 2–pyrazine can be obtained as a phase mixture with CuCl–pyrazine. Phase pure Cu 2Cl 2–pyrazine can only be synthesised via thermal decomposition of CuCl–pyrazine. This reaction was investigated using simultaneously difference thermal analysis and thermogravimetry measurements (DTA–TG), mass spectrometry, thermomicroscopy and temperature resolved X-ray powder diffraction.