Engineering solid state structural transformations of metal complexes

Solid state reactivity and structural transformation involving metal complexes driven by non-photochemical conditions are presented in this review. The single crystals preserved at the end of most of the reactions are discussed. These single-crystal-to-single-crystal (SCSC) reactions involving bond-breaking and making process by the non-photochemical routes are usually triggered by exposure of solvent vapors and gases, removal or exchange of solvents and guest molecules, heat, or their combinations. The structural transformations of simple metal complexes, metallamacrocycles, organometallic compounds and cages, for example, involve phase transitions accompanied by change in metal-metal bonding distances, change in coordination sphere and geometry, molecular association from monomers and dimers to tetramers and polymers, molecular rearrangements and isomerization, unexpected reactivity that were unknown in solution, and change of chirality.