文摘
The triplet excited state of a new crystalline form of a tetranuclear coordination d10鈥揹10-type complex, Ag2Cu2L4 (L = 2-diphenylphosphino-3-methylindole ligand), containing AgI and CuI metal centers has been explored using the Laue pump鈥損robe technique with 鈮?0 ps time resolution. The relatively short lifetime of 1 渭s is accompanied by significant photoinduced structural changes, as large as the Ag1路路路Cu2 distance shortening by 0.59(3) 脜. The results show a pronounced strengthening of the argentophilic interactions and formation of new Ag路路路Cu bonds on excitation. Theoretical calculations indicate that the structural changes are due to a ligand-to-metal charge transfer (LMCT) strengthening the Ag路路路Ag interaction, mainly occurring from the methylindole ligands to the silver metal centers. QM/MM optimizations of the ground and excited states of the complex support the experimental results. Comparison with isolated molecule optimizations demonstrates the restricting effect of the crystalline matrix on photoinduced distortions. The work represents the first time-resolved Laue diffraction study of a heteronuclear coordination complex and provides new information on the nature of photoresponse of coinage metal complexes, which have been the subject of extensive studies.