Electronic and resonance Raman spectra of [Au2(CS3)2]2-. Spectroscopic properties of a "short" Au(I)-Au(I) bond

Photoinduced single-crystal-to-single-crystal phase transition and photosalient effect of a gold(i) isocyanide complex with shortening of intermolecular aurophilic bonds

We report the first photoinduced single-crystal-to-single-crystal phase transition of a gold complex that involves shortening of intermolecular aurophilic bonds. The gold(i) isocyanide complex also shows a photosalient effect.

We report the first photoinduced single-crystal-to-single-crystal (SCSC) phase transition of a gold complex that involves the shortening of intermolecular aurophilic bonds. This is also the first solid state photochromism of a gold complex. Upon UV irradiation, the blue-emitting crystals of the gold(i) isocyanide complex 1 (1B) transform into the weakly yellow-emitting polymorph 1Y. X-ray diffraction analyses reveal that this phase transition proceeds in an SCSC manner. After phase transition from 1B to 1Y, the intermolecular Au···Au separation decreases from 3.5041(14) to 3.2955(6) Å, resulting in a red-shifted emission. The photoinduced shortening of the aurophilic bond in the excited state initiates the change in the crystal structure from 1B to 1Y. Moreover, the crystal 1B showed a photosalient effect: the 1B crystals jump upon irradiation with strong UV light owing to the phase transition into 1Y. The aurophilic bond formation in the crystal generates the mechanical movement of the crystal.

Forty-five years of chemical discovery including a golden quarter-century

Inorganic chemistry became a passion for me as a graduate student in the 1950s. It was exciting to be part of the renaissance of the discipline, and I am pleased to have contributed to its strength. Physical concepts applied to the understanding of the properties of transition metal compounds guided our work initially. In the 1970s, probably as a direct result of the world abandoning the gold standard, the chemistry of gold was awakened after a long sleep. Much of the chemistry covered in this review of our work relates to novel compounds of gold and the properties they display which have been uncovered during the last 25 years of the 20th century. Stable metal-metal bonded Au(II) and organometallic Au(III) compounds, bi- and trimetallic oxidative addition, phosphorescent species with microsecond lifetimes, gold chains resulting from aurophilic bonding stronger than H-bonding, and recently, gold binding to organic pi acids have intrigued my group and other gold chemists during this period.