Quantum Numbers and Photoelectron Spectroscopy

Magnetic Quantum Number (m)

Indicates orbital orientation in space.

Orbital Orientation

Determined by the value of l.

Value of l

Determines the shape of the orbital.

s-Orbital

Has 1 orientation.

p-Orbitals

Have 3 orientations.

d-Orbitals

Have 5 orientations.

f-Orbitals

Have 7 orientations.

Spin Quantum Number (ms)

Describes electron spin direction.

Spin States

Electrons can be spin up or spin down.

Pauli Exclusion Principle

No two electrons can have identical quantum numbers.

Hund's Rule

Electrons fill orbitals singly before pairing.

Aufbau Principle

Electrons fill lowest energy orbitals first.

Photoelectron Spectroscopy (PES)

Technique to measure electron binding energies.

Ionization Energy

Energy required to remove an electron.

Binding Energy Formula

E = hv - KE.

Core Electrons

Inner shell electrons, harder to remove.

Valence Electrons

Outer shell electrons, easier to remove.

PES Spectrum

Graph showing electron counts vs binding energy.

Kinetic Energy (KE)

Energy of ejected electrons in PES.

X-Ray Photon Energy (hv)

Energy of X-ray used in PES.

Subshells

Groups of orbitals with the same n and l.

Energy Level Diagram

Visual representation of electron orbitals.

Electron Orbitals

Regions where electrons are likely found.

Relative Number of Electrons

Indicates how many electrons occupy subshells.

Sublevel Symbols

s, p, d, f represent orbital shapes.

Electron Configuration

Notation describing electron distribution in orbitals.

PES Peaks

Correspond to electrons in different subshells.

Shielding Effect

Core electrons shield valence electrons from nucleus.

Magnetism

Unpaired electrons cause magnetic properties.

Energy Shells

Layers of orbitals around the nucleus.

Electron Count

Total number of electrons in an atom.

Quantum Numbers

Set of numbers describing electron states.