Synthesis, crystal structure, and luminescence properties of complexes (4-ViBnNMe3)2[{M6(µ3-I)8}I6] (M = Mo, W; (4-ViBnNMe3)+ is trimethyl(4-vinylbenzyl)ammonium)

Mo6 cluster-based compounds for energy conversion applications: comparative study of photoluminescence and cathodoluminescence

“…The analysis of the curves reveals two behaviors: (i) for 1 , 4 , 5 , and 6 , a plateau with the maximum QY value is observed followed by a loss of efficiency as the excitation wavelength increases; (ii) for 2 and 7 , a smooth increase of QY is observed from 300 nm to roughly 550 nm. These different behaviors evidence that the emission strongly depends on the environment of the metallic Mo 6 clusters: on one hand, the effect of X i inner and L a apical ligands forming the [] 2− unit, and, on the other hand, the effect of counter-cations [45]. It is worth noting that for 2 , 5 , and 6 that are based on the same [] 2− cluster unit, but differing in the nature of counter-cations, the two behaviors are found.…”

“…On the other hand, Kirakci et al reported, by a comparative method with cresyl violet as reference upon excitation at 440 nm, that the QYs of (TBA) 2 [], (TBA) 2 [], and (TBA) 2 [] in acetonitrile solution are 15%, 13%, and 12%, respectively [30]. More recently, the QY of (TBA) 2 [] measured on powder upon excitation at 400 nm was reported to be 10% [45]. It is worth noting that the QY of parent compound (4-ViBnNMe 3 ) 2 [] (4-ViBnNMe 3 = trimethyl(4-vinylbenzyl)ammonium) measured on powders by the same authors and in the same conditions as (TBA) 2 [] is only 1%.…”

Molybdenum Iodides – from Obscurity to Bright Luminescence

“…Another evidence for influence of outer sphere interactions on phosphorescence is given by the fact that the Φ em drops from 10 % for (Bu 4 N) 2 [Mo 6 I 14 ] (powder) to 0.01 % for the salt with 4‐vinylbenzyltrumethylammonium, (4‐VinBnNMe 3 ) 2 [Mo 6 I 14 ]. This was explained by energy dissipation through the aromatic system in the cation …”

Luminescent coordination polymers based on Ca2+ and octahedral cluster anions [{M6Cli8}Cla6]2− (M = Mo, W): synthesis and thermal stability studies

“…l em observed within the current study for (Bu 4 N) 2 The effect of the cationic part on the luminescence properties of octahedral anionic clusters have been discussed in several earlier works, where reasons such as energy transfer from the excited metal cluster to the cationic unit, in particular to the aromatic part of the cationic unit and self-absorption by the material, were discussed. [46][47][48][49][50] -core, the perturbation to the cluster core influences strongly the emission properties. 51 The careful evaluation of the distances between the centers of cluster anions shows that in the case of the Ca compounds the shortest distances between neighbouring cluster anions (12.466 Å for 1 and 13.051 Å for 3) are significantly longer than that for the Bu 4 N + compounds (8.645 Å).…”