Atomically Precise Platinum Carbonyl Nanoclusters: Synthesis, Total Structure, and Electrochemical Investigation of [Pt₂₇(CO)₃₁]^4- Displaying a Defective Structure.

ABSTRACT: The molecular Pt nanocluster [Pt₂₇(CO)₃₁]^4- (1^4-) was obtained by thermal decomposition of [Pt₁₅(CO)₃₀]^2- in tetrahydrofuran under a H₂ atmosphere. The reaction of 1^4- with increasing amounts of HBF₄·Et₂O afforded the previously reported [Pt₂₆(CO)₃₂]^2- (3^2-) and [Pt₂₆(CO)₃₂]^- (3^-). The new nanocluster 1^4- was characterized by IR and UV-visible spectroscopy, single-crystal X-ray diffraction, direct-current superconducting quantum interference device magnetometry, cyclic voltammetry, IR spectroelectrochemistry (IR SEC), and electrochemical impedance spectroscopy. The cluster displays a cubic-close-packed Pt₂₇ framework generated by the overlapping of four ABCA layers, composed of 3, 7, 11, and 6 atoms, respectively, that encapsulates a fully interstitial Pt₄ tetrahedron. One Pt atom is missing within layer 3, and this defect (vacancy) generates local deformations within layers 2 and 3. These local deformations tend to repair the defect (missing atom) and increase the number of Pt-Pt bonding contacts, minimizing the total energy. The cluster 1^4- is perfectly diamagnetic and displays a rich electrochemical behavior. Indeed, six different oxidation states have been characterized by IR SEC, unraveling the series of 1^n- (n = 3-8) isostructural nanoclusters. Computational studies have been carried out to further support the interpretation of the experimental data.

SUBMITTER: Cesari C 

PROVIDER: S-EPMC9387524 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature