A Semiempirical Quantum Approach to the Formation of Carbon Dioxide Adsorbates on Pt(100) and Pt(111) Cluster Surfaces

Abstract

The geometries and binding energies of CO2 adsorbates on Pt(100) and Pt(111) cluster surfaces were calculated by means of an improved version of the extended Hü ckel molecular orbital method. The polarization of the surface by an applied electric potential and coadsorption of H atoms were included in the model. For simulated applied potentials in the range -1.0 to 1.0 V, CO2 coordination geometries (side-on, formate) involving two adsorbate atoms bonded to the surface are favored, regardless the surface topology and the presence of coadsorbed H atoms. In agreement with experiment, larger binding energies are always calculated for the Pt(100) cluster surface.a VSIP ≡ valence state ionization potential. b oe1,2 ≡ orbital exponents of the base generating functions. c c1,2 ≡ linear coefficients of the double zeta Pt d-orbitals.

Benchmarking Semiempirical Methods To Compute Electrochemical Formal Potentials

“…Interestingly, the slope of the predicted E°value with computed orbital shift is −1.237, significantly different from the slope of −1 assumed in our previous work developing the OESA model 44 and in similar earlier models. 24,47,77 This slope is nearly identical to that seen for PM7 in the EDA model but significantly larger than the slopes of −0.8 to −0.9 seen in previous DFT models. 16,17 Since the current benchmarking is limited to molecules in ACN, this suggests the need for benchmarking to high-quality experimental data in other solvents to learn more about general trends and enable prediction of formal potentials in a broader range of environments.…”

CO2 methanation over heterogeneous catalysts: recent progress and future prospects

“…It has been proposed that the rate-limiting step is either the formation of the intermediate CH x O and its interaction with hydrogen or the formation of surface carbon in CO dissociation and its hydrogenation. 90 Numerous studies have been conducted on the adsorption and activation of CO 2 on metal surfaces such as Cu, 91 Pt, 92 Pd, 93 and Fe 91 where the Fe(110) surface has been identified to be most suitable for CO 2 activation. 94 This has been attributed to a remarkable charge transfer (0.83 e−) from the surface to the CO 2 molecule and to the elongation of one of the C-O bonds (to ca.…”

Influence of configuration of carboxylic acid capping ligands on the salt-induced aggregation of gold clusters

“…The exact configuration that a certain carboxylic acid group adopted is a result of its concentration on the surface of the colloid, independent of the colloid shape or crystal face [12]. The different configurations of Ox and CBTCA on gold colloid surface are not hard to understand.…”