Abstract
Aryl gold isocyanide complexes are found to have interesting photoluminescence properties in the solid state, being referred to as luminescence mechanochromism and molecular domino. A gold complex containing two gold atoms, {[pentafluorophenylgold]2(μ-1,4-diisocyanobenzene)}, shows significant change in its luminescence property when mechanical stimulus such as grinding or pressing is applied on its solid sample. This “luminescence mechanochromism” is most probably attributed to a ground state structure change from the microcrystalline to the amorphous state accompanied to the optical properties alternations. Different feature observed in phenyl(phenyl isocyanide)gold(I) complex is “molecular domino”, where even a small mechanical stimulus can trigger the structure change of the entire crystal. This spontaneous structure change proceeded in a single-crystal-to-single-crystal fashion with the drastic emission color alternation. These features enable sub-molecular-level structure investigation with single X-ray crystallographic analysis and visual observation of the phase transition under UV light irradiation during the mechano-induced phase change.
