How to Predict an Element from Its Photoemission Spectrum - Part 2

The energies of the electrons in a given shell/orbit can be measured with photoemission spectroscopy or photoelectron spectroscopy (PES) experimentally.


The position of each peak in the PES is related to the energy required to withdraw an electron from the corresponding subshell/orbital, and the relative height of each peak is typically proportional to the number of electrons in that orbital.

Question:

The PES for H & He are represented below. What accounts for the fact that the peak on the He spectrum is farther to the left and higher than the peak on the H spectrum?



Click/tap to enlarge the image

Solution:



Click/tap to enlarge the image

Pestering PES❓ Let Chemaficionado know in the comments below or at mychemistryhomework@gmail.com❗

Reference:

Photoemission spectroscopy. Wikipedia. https://en.wikipedia.org/wiki/Photoemission_spectroscopy.

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