Collision-Induced Dissociation of Undecagold Clusters Protected by Mixed Ligands [Au₁₁(PPh₃)₈X₂]⁺ (X = Cl, C≡CPh)

Abstract

We herein investigated collision-induced dissociation (CID) processes of undecagold clusters protected by mixed ligands [Au 11 (PPh 3 ) 8 X 2 ] + (X = Cl, C≡CPh) using mass spectrometry and density functional theory calculations. The results showed that the CID produced fragment ions [Au x (PPh 3 ) y X z ] + with a formal electron count of eight via sequential loss of PPh 3 ligands and AuX(PPh 3 ) units in a competitive manner, indicating that the CID channels are governed by the electronic stability of the fragments. Interestingly, the branching fraction of the loss of the AuX(PPh 3 ) units was significantly smaller for X = C≡CPh than that for X = Cl. We ascribed the effect of X on the branching fractions of dissociations of PPh 3 and AuX(PPh 3 ) to the steric difference.

Isomeric Effect of Mercaptobenzoic Acids on the Synthesis, Stability, and Optical Properties of Au25(MBA)18 Nanoclusters

“…CID on gold NCs in mass spectrometers was reported in previous works for different charge states, in both positive and negative modes, and with different ligands. 25,37−40 Usually, whatever the ligand, CID experiments lead to dissociation of the protecting ligand staples and formation of ions with higher- m / z ratios. Of note, the nature (protonation, deprotonation, counterion adducts, etc) as well as the number of charges affect the fragmentation pattern; however, the obtained fragments are not sufficient for structural characterization.…”

Halogen effects on the electronic and optical properties of Au13nanoclusters

“…The PL intensities are stronger than those reported previously for gold clusters. 5,[17][18][19][20] We further employed PLE spectroscopy to obtain a higher signal-to-noise ratio for the band features of the [Au 13 -X 2 ] clusters, as shown in Fig. 4C.…”

“…11,12 With the availability of single crystal X-ray structures, 13,14 extensive attention has been paid to the role of ligands in the syntheses and photophysical properties of gold nanoclusters with different nuclearities. 15,16 To obtain novel gold clusters with different photophysical properties, organic ligands such as thiols, phosphines and alkynes have been widely exploited in the syntheses of gold nanoclusters (Au n ) such as Au 8 , 17,18 Au 9 , 19 Au 11 , 20,21 Au 13 , [22][23][24][25][26][27] Au 18 , 27,28 Au 20 , 29,30 Au 22 , 31,32 Au 23 , 33 Au 24 , 34 Au 25 , 35,36 Au 32 , 37 Au 37 , 38 Au 44 , 39 Au 52 , 40 Au 55 , 41 and Au 102 . 13 Among all of the gold nanoclusters that have been structurally characterized, icosahedral Au 13 nanoclusters have been more extensively studied due to their highly symmetrical structure and prominent photoluminescence properties.…”

Ligand engineering of immobilized nanoclusters on surfaces: ligand exchange reactions with supported Au11(PPh3)7Br3

“…3), the main fragments of Au 11 clusters were found, which can be assigned to [Au 11 (PPh 3 ) x Br 2 ] + , [Au 10 (PPh 3 ) x Br] + and [Au 9 (PPh 3 ) x ] + fragments, in agreement with the fragmentation pathway proposed for PPh 3 protected undecagold by Tsukuda and coworkers. 52 Additionally, the sample after exposure to GSH [Au 11 :GSH] also showed peaks indicating exchanged clusters containing SG − instead of Br − . The fragments [Au 11 (PPh 3 ) 6 (SG) 2 ] + (marked with *), as well as [Au 10 (PPh 3 ) 7 SG] + (marked with **) and [Au 10 (PPh 3 ) 6 SG] + , could be detected.…”