research papers
An iron(III) calix[4]pyrrolidine complex undergoes a slow phase transformation at ca 173 K from monoclinic space group P21/n to the maximal non-isomorphic subgroup, triclinic space group P, which is accompanied by nonmerohedral twinning. The NH H atoms are directed below the planes of the macrocycles and are hydrogen bonded to the coordinated Cl− ions. There are also intramolecular C—HCl hydrogen bonds present in both forms.
research papers
On heating a crystal of the one-dimensional coordination polymer catena-poly[[diaqua(sulfato)copper(II)]-2-glycine] to 435 K in an oven, its aspect changed from blue to a very pale blue. Crystal structure analysis indicated that it had undergone a single-crystal to single-crystal (SCSC) solid-state transformation, losing two water molecules and forming a two-dimensional coordination polymer, viz. poly[2-glycine-4-sulfato-copper(II)].