Intense blue emission and a reversible hypsochromic shift of luminescence caused by grinding based on silver(i) complexes

Abstract

Highly blue-emissive silver(i) complexes bearing N-heterocyclic carbene and diphenylphosphinobenzene were newly synthesized. The reversible hypsochromic shift of the emission by the grinding process was observed.

Synthesis and Photophysical Properties of Emissive Silver(I) Halogenido Coordination Polymers Composed of {Ag2X2} Units Bridged by Pyrazine, Methylpyrazine, and Aminopyrazine

“…Compared to that of copper­(I) and gold­(I) complexes, the development of luminescent silver­(I) complexes has started only recently; however, several silver complexes exhibiting strong luminescence at room temperature, − thermally activated delayed fluorescence, − thermochromic luminescence, − and stimuli-responsive luminescence , have already been reported. Because the coordination properties and electronic structures of silver­(I) complexes are similar to those of copper­(I) complexes, the ligands affording luminescent copper­(I) complexes have also been exploited to synthesize luminescent silver­(I) complexes. ,− The obtained complexes typically display emission in the near-ultraviolet (UV) or blue region even though the corresponding copper­(I) complexes show colorful emission in the visible region. ,− Because the stability of the 4d orbitals of the silver­(I) center is higher than that of the 3d orbitals of the copper­(I) center, ,− the metal-to-ligand CT ES increases in energy, approaching those of the other ESs, which causes a mixing of the ESs and complicates their emissive ESs, hampering the rational design of a ligand set for luminescent silver­(I) complexes.…”

“…7−9 Copper(I) complexes are also known to be sensitive to metal−metal interactions in the case of cluster complexes, 10−12 whereas their emissive energies (i.e., their colors) can be controlled by the acceptor orbitals of the ligands because the emissive ESs of copper (I) complexes have charge-transfer (CT) characteristics in many cases. 13−18 Compared to that of copper (I) and gold(I) complexes, the development of luminescent silver(I) complexes has started only recently; however, several silver complexes exhibiting strong luminescence at room temperature, 19−24 thermally activated delayed fluorescence, 21−25 thermochromic luminescence, 26−31 and stimuli-responsive luminescence 32,33 have already been reported. Because the coordination properties and electronic structures of silver(I) complexes are similar to those of copper(I) complexes, the ligands affording luminescent copper(I) complexes have also been exploited to synthesize luminescent silver(I) complexes.…”

Osmaindenes: Synthesis and Reversible Mechanochromism Characteristics

“…Based on an extensive literature search, [28][29][30] we speculate that mechanical stimulation may lead to changes in the molecular morphology of these complexes, which may also be responsible for its reversible mechanochromism behavior. Therefore, in order to further study the mechanochromism behavior, three different solid states of these complexes were tested by X-ray diffraction (XRD) measurements.…”

Synthesis and Thermochromic Luminescence of Ag(I) Complexes Based on 4,6-Bis(diphenylphosphino)-Pyrimidine

“…As a result, (M + L')LCT excited states can be generated, thereby inducing thermally activated delayed fluorescence (TADF) in Ag(I) compounds [22][23][24][25][26][27][36][37][38][39][40][41][42]. In the context of OLED application, it is relevant to note that the (M + L')LCT emission of Ag(I) benefits over that of Cu(I) analogues since the former (i) is shorter in the lifetimes [36,41,42], and (ii) generally appears in the higher energy domain [36,37,39,[43][44][45]. On the whole, Ag(I) compounds that emit apparent luminescence at ambient temperature, especially, that of TADF nature, are still rare.…”