Wave Particle Duality* *Information for this presentation was taken from ASU PHY 540 and “Chemical Bonding Clarified Through Quantum Mechanics” by George C. Pimemtel and Richard D. Spratley

“Energy transfer is accompanied by a mass transfer and every mass, whether moving or not, represents a store of energy” E α m The proportionality constant between these units is c 2 E = mc 2 Einstein proposed this in 1905 as a model to explain how energy and mass are simply different materializations of the same thing.

E=mc 2 Energy has massMass is energy Since energy and mass are the same thing, the conservation laws of the two are now bonded Physics and chemistry got married!

E=mc 2 Energy has massMass is energy Light from a hot source is continuous and Blackbody radiation shows a continuous spectrum Radiation intensity from a given source changes with temperature

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Smaller and smaller pieces of a type of stuff look the same.

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate but While matter looks continuous, its properties are explained with a particulate model

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut Is light also particulate? so Now, we must confront the essential question…

Now for a little derivation =D E=mc 2 The general equation for the light-energy relationship

Now for a little derivation =D E=mc 2 E=hν For light, energy is proportional to Planck’s constant (h) times frequency (ν)

Now for a little derivation =D E=mc 2 E=hν hν=m ν c 2 Substitute hν for E

Now for a little derivation =D E=mc 2 E=hν hν=m ν c 2 m ν= hν/c 2 Rearrange for m ν So, now our thought progression looks like this:

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut and But what about momentum?

This calls for another derivation ^.^ Momentum = mass (velocity) c is the speed of light So let’s add that to the thought progression

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut and

Now, let’s play pool XP θ φ

…and parallel that to the scattering of light θ φ λ e e λ’λ’ Incident light ray has a certain wavelength and a certain frequency reflected light ray has a different wavelength and a different frequency A.H. Compton proved that when electrons scatter x-rays, there is a momentum change.

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut and

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut and so Does matter have wave properties?

Let’s make sure we define the matter- wave property relationship :-] Momentum is connected to wavelength for light Let’s assume the same for mass And rearrange for wavelength The wave behavior of light can be proven using diffraction grating or crystals

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut and

E=mc 2 Energy has massMass is energy Light from a hot source is continuous Matter appears to be continuous and Atomic theory requires matter to be particulate andbut and Enter Quantum Mechanics!!!