Doublet Separations #

Pt 4f = 3.35 eV

Pt 4d = 16.9 eV

Pt 4p = 89 eV

Common Overlaps for Pt 4f #

Ni 3p – Cd 4p – Ra 5d – Tc 4s – Br 3d – Ta 5s – Au 5p – Al 2p – Cr 3s – Cu 3p – Ru 4s – Tl 5p – W 5s – In 4p – Cs 4d – Ac 5d – Hg 5p – Rh 4s – Re 5s – Au 4f – Mn 3s

Auger Energies #

Note – these are listed in KINETIC ENERGY

Pt NOO ≈ 165 eV

Common Binding Energies – Pt 4f #

Theory and Background #

Platinum is widely used in the chemical industry due to its exceptional catalytic properties and durability. It is found commonly in the fields of catalysis, energy materials, and in fundamental surface science – and as such has been studied extensively by XPS.

Pt is typically analysed by the 4f orbitals, which obey spin-orbit splitting rules with no deviation.

Experimental Advice #

If recording Pt/Alumina catalysts, recording the Al 2s region as well as the Al 2p/Pt 4f overlap enables peak area locking between the Al peaks and ensures accurate resolution of the Al species within the overlapping region.

Data Analysis Guidance #

Due to the difficulties mentioned above, it is therefore common to use the modified auger parameter (α‘) to assign chemistry, values for which may be found in table 1. To find auger parameters of many more compounds, see reference 5 from Mark Biesinger.

The modified auger paramater may also provide insight into specific nanoparticle chemistry via estimation of the relaxation energy (r).⁽⁶⁾ This may be defined as half the change in the modified auger parameter compared to bulk Cu (equation 1).⁽⁷⁾

r = 0.5 * (|1851.2 – α‘) Equation 1

Copper nanoparticles may evidence increased relaxation energies when an decreased number of copper atoms are screening the core-hole (i.e. smaller nanoparticles)⁽¹⁾ or due to a decrease in the polarizability of the support.⁽⁸⁾

Copper metal does not exhibit a high degree of asymmetry, due to it’s largely filled d-band. A lineshape of LA(1.05, 110) can be used to give a good fit for Cu metal.

When fitting copper doublets – do not constrain the FWHM of the doublets to be equal – due to the aforementioned Coster-Kronig broadening.

Reference Datasets #

Coming soon

References #