UV−Visible Absorption Spectra of Small Platinum Carbonyl Complexes and Particles: A Density Functional Theory Study

Abstract

We investigate the influence of a carbonyl coating on the UV-visible absorption of platinum complexes and particles with the TDDFT method. We first investigate the Chini clusters [Pt(3)(CO)(6)](n)(2-), n = 1-4, for which the absorption spectra are known. We show that PBE is realistic but displays convergence issues and that B3LYP overestimates intertriangle distances and absorption intensities. We discuss the structure of the spectra and the parallel vs perpendicular character of the transition dipole with respect to the stacking axis. We then investigate the spectra of model carbonylated platinum particles: [Pt(13)(CO)(12)](2-) (with only terminal carbonyls) and [Pt(13)(CO)(24)](2-) (with only bridging carbonyls). B3LYP proves much more realistic than in the case of Chini clusters. The influence of the morphology of the platinum particle and of the carbonyl coating on the absorption spectra is discussed. The results suggest an interpretation of a spectrum, recorded in a recent synthesis.

Electrocatalytic activity for oxygen reduction reaction of Pt nanoparticle catalysts with narrow size distribution prepared from (n=3–8) complexes

“…The peak wavelengths and colors of all the solutions agreed well with the previous data for ½Pt 3 ðCOÞ 3 ðl À COÞ 3 2À n complexes [16,17,20]. The n values determined from the literature [15][16][17]20] are summarized in Table 1. From the comparison between Ptan(12.5) and Pt-an(50) and between Pt-et(0) and Pt-et(50), as the water content was increased, the n value became smaller.…”

Shape-controlled continuous synthesis of metal nanostructures

“…High energy bands are also n dependent, but to a much lesser extent than the low energy bands. 43 Chini clusters with n = 4 (blue-green colour) and n = 5 (yellow-green) display a maximum in the visible band at 620 and 710 nm, respectively. 43 These values are in full agreement with the UV-Vis spectrum reported in Fig.…”

Alcohol to water catalyzed by Pt nanoparticles: an experimental and computational approach

“…These functional and basis sets have been checked to describe platinum particles with a good accuracy. 43 The solvent has been modeled with the help of the SMD method. 44 All the calculations have been done with the Gaussian 09 program.…”