Photoelectron Spectroscopy (PES)

• A technique used to measure the binding energy of electrons in an atom or molecule.– As in the photoelectric effect, electrons are

emitted from an atoms or molecule by radiation from a photon of Enery (Ephoton = hν)

– The emitted electrons are captured and their kinetic energy is calculatied

– Binding energy = energy of photon –kinetic energy E electron = hν – KE

– The closer an electron is to the nucleus the higher its binding energy.

PES Instrument Basics

Photoelectron Spectra

• Each peak corresponds to removal of electrons from a different sublevel.

• The peaks are ordered: 1s, 2s, 2p, 3s, 3p, 3d, 4s etc.

Photoelectron

Spectra• Identify the

sublevel that corresponds to each peak

• Draw the corresponding Bohr model of each atom

Try these

• Zumdahl examples page 440