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The stabilities of[M_(12)Ag_(32)(SR)_(30)]~(4-)(M = Ag,Au and SR = SPhF_2,SPhCF_3,SPhF) clusters having the same structure but different surface ligands or counter cations were systematically studied.It was clearly revealed that a subtle structural change in the surface ligands or counter cations could significantly alter the overall stability of[M_(12)Ag_(32)(SR)_(30)]~(4-) although they all had an electronic structure of 18-electron superatom shell closure.SPhF_2 was found as a better surface ligand than SPhCF_3 or SPhF to stabilize[M_(12)Ag_(32)(SR)_(30)]~(4-).And the use of more bulky[(PPh_3)_2N]~+ as the counter cations was revealed to be more deleterious to the overall stability of[M_(12)Ag_(32)(SR)_(30)]~(4-) clusters than PPh_4~+.[Au-(12)Ag_(32)(SR)_(30)]~(4-) was much more stable than[Ag_(44)(SR)_(30)]~(4-) with the same surface ligands and counter cations.An exceptional stability was observed on(PPh_4)_4[Au_(12)Ag-(32)(SPhF_2)_(30)]which was stable in DMF for more than 8 days in air at 80 C.More research efforts are still needed to deeply understand why a small structural change could result in a significant change in the stability of noble metal nanoclusters.
The stabilities of [M_ (12) Ag_ (32) (SR) _ (30)] ~ (4 -) (M = Ag, Au and SR = SPhF_2, SPhCF_3, SPhF) clusters have the same structure but different surface ligands or counter cations were systematically studied. It was clearly revealed that a subtle structural change in the surface ligands or counter cations could significantly alter the overall stability of [M_ (12) Ag_ (32) (SR) _ (30) ) although they all had an electronic structure of 18-electron superatom shell closure. SPhF_2 was found as a better surface ligand than SPhCF_3 or SPhF to stabilize [M_ (12) Ag_ (32) (SR) _ (30) -). And the use of more bulky [(PPh_3) _2N] ~ + as the counter cations was revealed to be more deleterious to the overall stability of [M_ (12) Ag_ (32) (SR) _ (30) (4-) clusters than PPh_4 ~ +. [Au- (12) Ag_ (32) (SR) _ (30)] ~ (4-) was much more stable than [Ag_ (44) (4) with the same surface ligands and counter cations. An exceptional stability was observed on (PPh_4) _4 [Au_ (12) Ag- (32) (SPhF_2) _ (30)] which was stable in DMF for more than 8 days in air at 80 C. More research efforts are still needed to deeply understand why a small structural change could result in a significant change in the stability of noble metal nanoclusters.