Circularly Polarized Luminescence from Chiral Tetranuclear Copper(I) Iodide Clusters

Abstract

Circularly polarized luminescent (CPL) materials are promising in applications such as 3D displays and quantum communication. Hybrid organic–inorganic copper­(I) iodides have been rapidly developed due to their intense photoluminescence and structural diversity; nevertheless, the reported Cu–I clusters rarely show CPL activities. In this study, we introduced chiral organic molecules R/S-methylbenzylammonium (R/S-MBA) into Cu–I inorganic skeletons to achieve chiral tetranuclear (R/S-MBA)4Cu4I4 clusters with intense orange luminescence and CPL activity at room temperature. These enantiomeric (R/S-MBA)4Cu4I4 clusters show oppositely signed circular dichroism (CD) signals, which agree well with their simulated electronic CD spectra. The crystallization-induced helical arrangement of (R/S-MBA)4Cu4I4 clusters and their largely distorted polynuclear configuration demonstrate a new platform for the study of chiral-related properties.

Circularly polarized luminescence of agglomerate emitters

“…[51][52][53] Furthermore, the method that the ground agglomerate samples are sandwiched between two quartz slides is also reported. [54] Moreover, although the above-mentioned improvement of the instrument and the sample preparation methods can effectively reduce the effect of artifacts, CPL signals are also susceptible to the experimental deviations. The agglomerate samples could be divided into two types, that is, (a) highly ordered samples including single crystals and LCs, and (b) randomly oriented samples, such as dispersed in KBr pellet, Nujol, and isotropic film.…”

“…Several days later, enantiomeric tetranuclear copper(I) clusters, (R/S-MBA) 4 Cu 4 I 4 , with intense orange CPL (PLQY, ≈60%), were easily designed and obtained by Tang's group. [54] Enantiomeric (R/S-MBA) 4 Cu 4 I 4 showed mirror image CD signals and CPL signals (g lum , ±1 × 10 −2 ) in the crystalline state (Figure 11F). In addition, further extended work was presented by Zhu et al, they assembled the thiolated [Au 1 Ag 22 (S-Adm) 12 ] 3+ (SC, where S-Adm = 1adamantanethiol) superatom cluster into a framework material through inorganic SbF 6…”

“…(F) The structures, CPL, and g lum spectra of (R/S-MBA) 4 Cu 4 I 4 clusters. Adapted with permission, [54] Copyright 2020, American Chemical Society. (G) The crystal structure and CPL spectra of SCIF-1, SCIF-2-Left, SCIF-2-Right.…”

Enantiomeric MOF Crystals Using Helical Channels as Palettes with Bright White Circularly Polarized Luminescence

“…In process, the ground solid‐state samples (a small amount) were uniformly sandwiched by two quartz slides to test. [ 32 ] Certainly, the instrument was carefully calibrated to eliminate influence of other factors and the reproducibility of CPL spectrum for each sample was confirmed by measuring at least three times.…”

Enhanced Circularly Polarized Luminescence Activity in Chiral Platinum(II) Complexes With Bis- or Triphenylphosphine Ligands

“…Especially these phosphorescent transition metal complexes, which have remarkable metal-center chirality, tunable emission properties, and unusually high phosphorescence efficiency, are receiving increasing interests in recent years (Han et al, 2018). Such CPL-active materials as Pt (Shen et al, 2014), Ir (Han et al, 2017;Hellou et al, 2017;Yan et al, 2019a), Au (Yang et al, 2020;Zhu et al, 2020), Cu (Jin et al, 2019;Deng et al, 2020;Yao et al, 2020), Zn (Aoki et al, 2017;Chen Y. et al, 2019) Cd (Deng et al, 2019), and Cr (Jiménez et al, 2019) complexes can exhibit various emission colors from blue to red. The dissymmetry factor g lum (g lum = 2 I/I = 2(I L -I R )/(I L + I R ), where I L and I R indicate, respectively, the intensity of the left and right circularly polarized light), can reach up to 10 −2 order.…”