Innovative Molecular Design Strategies in Materials Science Following the Aurophilicity Concept

Abstract

The past decade has seen a diverse range of breakthrough inventions that are derived from gold complexes, including the application of aurophilic interactions in the preparation of stimuli-responsive materials. Examples of these gold-based materials include aurophilicity-induced metallogelators, mechanochromic, thermochromic, vapochromic, and solvatochromic luminescent compounds, as well as sensory materials for the detection of metal ions. Sophisticated properties of gold complexes with Au•••Au contacts have been explored at the edge of several disciplines including chemistry, crystallography, molecular engineering and advanced materials. As science paves its way to innovation, cross-disciplinary research moves from being a luxury to becoming a necessity. Development of the concept of aurophilicity and its use in designing novel materials is a true example of innovation on a multidisciplinary platform. As miniaturization continues to influence the next generation of technological advancement, using the properties of molecules as chemical tools to enable such developments becomes extremely important. In this Review, recent examples of gold complexes which exhibit a response to external stimuli have been collected and some of their potential applications discussed for selected cases.

Re‐investigation of Barium‐Gold(I)‐Tetra‐Thiostannate(IV), Ba[Au2SnS4], with Short AuI···AuI Separation Showing Luminescence Properties

“…Whether a relationship between the energy of the luminescence and the Au ··· Au separation can be established for three dimensional Au I containing materials requires characterization of many more compounds. Finally, we would like to refer to two very recently published reviews, [ 78,79 ] which also seem interesting in connection with this article and the title compound. The first review deals with innovative molecular design strategies in materials science that follow the aurophillic concept.…”

Stimuli‐Responsive AIEgens

“…This work suggests that the intermolecular rearrangements in some special systems are easy to occur upon external mechanical stimuli owing to the existence of strong intermolecular interactions, such as π–π interactions or aurophilic interactions, which can be visualized by conspicuous changes in luminescence. [ 117–119 ]…”

Seeing luminescence appear as crystals crumble. Isolation and subsequent self-association of individual [(C6H11NC)2Au]+ions in crystals

“…17 A molecular box based on connecting six gold(I) centers with a non-emissive triphosphine ligand has produced a pressure sensitive salt whose structure and luminescence changes upon grinding. 18 Materials involving gold(I) complexes are frequently luminescent [19][20][21] and particularly prone to sensitivity to environmental factors including responses to mechanical pressure or organic vapors. 6,10,14,22 Linear, two-coordinate gold(I) complexes frequently self-associate in the solid state to form dimers, trimers, and extended, nearly linear chains.…”

“…obtain a benzene solvate of [(C 6 H 11 NC) 2 Au](PF 6 ) have not been successful.Crystals of the benzene solvates are isostructural and form in the tetragonal space group P4/mnc (128). Gold ions are separated by 6.9717(19)Å in [(C 6 H 11 NC) 2 Au](SbF 6 )$C 6 H 6 (7) and by 6.936(2)Å in [(C 6 H 11 NC) 2 Au](AsF 6 )$C 6 H 6…”