Fine-Tuning of Luminescence through Changes in Au–S Bond Lengths as a Function of Temperature or Solvent

Abstract

The luminescent properties of gold­(I)–sulfur compounds have received much attention for their potential applications in the sensing field. The molecular level regulation of luminescence remains a challenge. It is critical to unravel the relationship between the luminescence and the structure. Herein we report a binuclear complex [Au2(dppaptc)2]­Cl2 (1, dppaptc = N,N-bis­(diphenylphosphanylmethyl)-amino-4-phenyl-thiocarbamide), which exhibits variations at Au–S bond lengths as a function of temperature or solvent. X-ray analysis reveals a linear decrease from 2.900(3) to 2.745(15) Å upon cooling 1·2CHCl3 from 300 to 80 K combined with a linear correlation with its luminescence intensity at 475 nm, which was confirmed by TD-DFT calculations. Compound 1, if solvated with H2O and alcohol, possesses the shorter Au–S bonds and enhanced luminescence. The close relationship between luminescence intensity and Au–S length serves as a complement to existing luminescent gold­(I)–sulfur systems and provides some insight into understanding the thermochromism and solvatochromism of the gold­(I)–sulfur compounds.

Giant Emission Enhancement of Solid‐State Gold Nanoclusters by Surface Engineering

“…also found that a change of Au−S bond length can dramatically affect the luminescence of the complexes. A decrease of the Au−S bond length was associated with an increase of the luminescence intensity, similar to our observations. Apart from the change of Au−S bond length, the size of Au 13 core (Au i −Au c distances) also plays an important role in the emission enhancement observed here.…”

Highlights on Gold TADF Complexes

“…X-ray crystal structure resolution shows that two 6 + cations sandwich the n-alkane (hexane) molecule at both ends via CH/π interactions, and that the THF molecule has an intermolecular CH/π interaction with one bridged phenylene unit of the diphosphine ( Figure 5). The demonstration that this is a field increasing in interest and starting to be explored by other groups comes from a very recent publication in 2019, from the group of J.-P. Lang and collaborators [29], with the preparation and study of a P-S multifunctional dinuclear Au(I) complex 7. The ligand bridges two Au(I) centers, and each Au(I) is tetrahedrally coordinated by two P atoms and two bridging S atoms from two ligands that form the central, centrosymmetric [Au2S2P4] rhombus.…”

Reversible luminescence tuning behavior in a thermal-stimuli-responsive anthracene-based coordination polymer

“…To meet the high security requirements of the market, encrypted information recorded by stimulus-responsive materials that can only be disclosed under an external stimulus provides an enhanced security level. Stimulusresponsive functional materials are usually functional materials with structurally switchable behavior that demonstrate changes in response to pH levels, [10][11][12] thermal stimuli, [13][14][15][16] light, [17][18][19][20] or chemical gas. [21][22][23][24][25] Thermochromic luminescent materials, as an attractive class of stimulusresponsive materials, have been developed rapidly due to their fast response upon stimulation, environmental protection, easy operation, and high fatigue resistance.…”