A precise hexagonal octadecanuclear Ag macrocycle with significant luminescent properties

Abstract

The first hexagonal octadecanuclear Ag macrocycle [Ag(18)(TTTMB)(12)](NO(3))(18)·30H(2)O has been hydrothermally synthesized. The outside and inner diameters of the unprecedented architecture are about 27.72(13) Å and 15.37(7) Å, respectively. This complex displays a huge increase in the intensity and lifetime of phosphorescence with decreasing temperature.

Argentophilic Interactions

“…In bi-or polynuclear silver complexes of these ligands with short Ag-Ag contacts the emissions are found strongly red-shifted, and the effect is plausibly assigned to LMCT processes "perturbed by Ag-Ag interactions" (LMMCT). [113][114][115][116][117] The strong temperature dependence of the emission maximum and intensity of a complex with multiple argentophilic contacts is shown in Figure 3. The .…”

“…The effect has been ascribed to the decrease in Ag-Ag contacts at low temperature. [116] Concentration-dependent emission was observed for a compound prepared from a chromophore (chr) 28 a and the trinuclear silver 3,5-bis(trifluoromethyl)pyrazolide [Ag 3 -(pyr) 3 ] (28 b). Crystals of this product show a dinuclear cation where the two (chr)Ag silver units are bridged by a pyr ligand, and the counterion is a pentanuclear cluster [Ag 5 (pyr) 6 ] À with a quasi-square pyramidal configuration.…”

Argentophile Wechselwirkungen

“…In zweioder mehrkernigen Silberkomplexen derartiger Liganden mit kurzen Ag···Ag-Kontakten sind die Emissionen stark rotverschoben, und dieser Effekt wird mit "durch Ag···Ag-Wechselwirkungen beeinflusste" LMCT-Prozessen plausibel gemacht (LMMCT). [113][114][115][116][117] Die starke Temperaturabhängigkeit von Emissionsmaximum und -intensität eines Komplexes mit vielen argentophilen Kontakten ist in Abbildung 3 gezeigt. Der Effekt wird stärkeren argentophilen Wechselwirkungen bei tieferen Temperaturen zugeschrieben.…”

A novel 3D homochiral helical coordination polymer based on a flexible tripodal ligand

“…1,3,5-tri(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethylbenzene (tttmb) is one of the flexible tripodal ligands with a benzene ring and N-donors, which is a good bridging ligand for the construction of diverse structures [19][20][21]. On the one hand, the 1,2,4-triazole groups of tttmb ligands present strong and typical coordination capacity and can provide more potential coordination sites.…”

“…Among them, the design and selection of organic ligands with suitable binding groups are especially important [13,14]. In fact, flexible tripodal ligands have been proven to be a kind of most potential organic building blocks in construction of coordination polymers for their outstanding features of flexible coordination fashions [15][16][17][18].1,3,5-tri(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethylbenzene (tttmb) is one of the flexible tripodal ligands with a benzene ring and N-donors, which is a good bridging ligand for the construction of diverse structures [19][20][21]. On the one hand, the 1,2,4-triazole groups of tttmb ligands present strong and typical coordination capacity and can provide more potential coordination sites.…”