What Did Einstein Say About Light?

It is both a wave and a particle.

Louis de Broglie, (France, 1892-1987)Wave Properties of Matter (1923)

-Since light waves have a particle behavior (as shown by Einstein in the Photoelectric Effect), then particles could have a wave behavior.

-He suggested electrons could be considered waves confined to a space around an atomic nucleus

Light versus Electron Diffraction

Electrons: Waves and Particles?

Big problem …. If electrons are both particles and waves, then where are they in the atom?

Werner Heisenberg: Uncertainty Principle

We can not know both the position and momentum of a particle at a given time. (1927)

Erwin Schrodinger, 1925Quantum (wave) Mechanical

Model of the Atom

-Developed equation (wave equation)that treated electrons in atoms as waves.

-Only waves of specific energies providedsolutions to his equation.

-Along with Heisenberg principle, this waveequation laid the foundation for modernquantum theory

Be Curious … Although Curiousity Killed the Cat

Schrodinger’s Cat

Hugh Everett

What Schrodinger’s Equation Means to Chemists

-Electrons do not travel around the nucleus in neat orbits.

-We only have a probability of finding an electron at a givenplace around the nucleus.

-Electrons exist in orbitals that have three dimensional shapes.These orbital shapes are described by the solutions to Schrodinger’s wave equation for different energies.

-Property of orbitals can be described by 4 quantum numbers.

Four Quantum Numbers

-Principal Quantum Number (n)

-Orbital Quantum Number (l)

-Magnetic Quantum Number (m)

-Spin Quantum Number