Abstract
Size and shape determination of ultrasmall gold superatoms passivated by protecting ligands, is a fundamental concern towards the obtention of efficient tunable building blocks. In this report, we pursue a further understanding of the energetic terms ruling the core-shape determination in the first two 2-cluster electron gold selenido clusters reported to date. Our results show that the ultrasmall [Au8Se2(L)4]2+ series featuring an Au4 tetrahedron with two separated exo Au2Se units (core type a), and a Au4 tetrahedron with two connected Au2Se units resulting in a distorted hexagonal Au6 ring (core type b), obtained for L = PPh2CH2PPh2 (dppm) and L = PPh2(CH2)2PPh2 (dppe), respectively. The more favorable adppm arrangement by 5.7 kcal·mol−1 over bdppm, by the less repulsive Pauli repulsion term by 13.9 kcal·mol−1, and the more stabilizing electrostatic character (29.4 kcal·mol−1), and London dispersion (12.4 kcal·mol−1), despite the more favorable contribution from orbital interactions and solvation (−46.4 kcal·mol−1, and, −3.6 kcal·mol−1, respectively) in the later. For bdppe arrangement, a more favorable situation is found by 11.5 kcal·mol−1 in comparison to adppe, determined by the leads to a more stabilizing contribution from electrostatic (31.5 kcal·mol−1), orbital (1.8 kcal·mol−1), London dispersion (11.9 kcal·mol−1) contributions, despite to offer a more steric hindered situation. Such structural preference is in line with experimental findings, allowing comparison of the relative stability of clusters bearing different ligand layers, enabling further shape-property relationship exploration in gold clusters. In addition, optical spectrum features are evaluated. Lastly, sulfido and tellurido hypothetical counterparts denote similar structural preferences.
Original language | English |
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Article number | 121149 |
Journal | Inorganica Chimica Acta |
Volume | 542 |
DOIs | |
State | Published - 2022 |
Bibliographical note
Funding Information:This work was supported by FONDECYT 1221676.
Publisher Copyright:
© 2022 Elsevier B.V.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry