Thiol Ligand-Induced Transformation of Au<sub>38</sub>(SC<sub>2</sub>H<sub>4</sub>Ph)<sub>24</sub> to Au<sub>36</sub>(SPh‑<i>t</i>‑Bu)<sub>24</sub> Chenjie Zeng Chunyan Liu Yong Pei Rongchao Jin 10.1021/nn401971g.s001 https://acs.figshare.com/articles/journal_contribution/Thiol_Ligand_Induced_Transformation_of_Au_sub_38_sub_SC_sub_2_sub_H_sub_4_sub_Ph_sub_24_sub_to_Au_sub_36_sub_SPh_i_t_i_Bu_sub_24_sub_/2393989 We report a disproportionation mechanism identified in the transformation of rod-like biicosahedral Au<sub>38</sub>(SCH<sub>2</sub>CH<sub>2</sub>Ph)<sub>24</sub> to tetrahedral Au<sub>36</sub>(TBBT)<sub>24</sub> nanoclusters. Time-dependent mass spectrometry and optical spectroscopy analyses unambiguously map out the detailed size-conversion pathway. The ligand exchange of Au<sub>38</sub>(SCH<sub>2</sub>CH<sub>2</sub>Ph)<sub>24</sub> with bulkier 4-<i>tert</i>-butylbenzenethiol (TBBT) until a certain extent starts to trigger structural distortion of the initial biicosahedral Au<sub>38</sub>(SCH<sub>2</sub>CH<sub>2</sub>Ph)<sub>24</sub> structure, leading to the release of two Au atoms and eventually the Au<sub>36</sub>(TBBT)<sub>24</sub> nanocluster with a tetrahedral structure, in which process the number of ligands is interestingly preserved. The other product of the disproportionation process, <i>i</i>.<i>e</i>., Au<sub>40</sub>(TBBT)<sub><i>m</i>+2</sub>(SCH<sub>2</sub>CH<sub>2</sub>Ph)<sub>24–<i>m</i></sub>, was concurrently observed as an intermediate, which was the result of addition of two Au atoms and two TBBT ligands to Au<sub>38</sub>(TBBT)<sub><i>m</i></sub>(SCH<sub>2</sub>CH<sub>2</sub>Ph)<sub>24–<i>m</i></sub>. The reaction kinetics on the Au<sub>38</sub>(SCH<sub>2</sub>CH<sub>2</sub>Ph)<sub>24</sub> to Au<sub>36</sub>(TBBT)<sub>24</sub> conversion process was also performed, and the activation energies of the structural distortion and disproportionation steps were estimated to be 76 and 94 kJ/mol, respectively. The optical absorption features of Au<sub>36</sub>(TBBT)<sub>24</sub> are interpreted on the basis of density functional theory simulations. 2013-07-23 00:00:00 theory simulations TBBT ligands nanocluster distortion activation energies spectroscopy analyses biicosahedral tetrahedral structure reaction kinetics absorption features disproportionation mechanism disproportionation steps ligand exchange disproportionation process