Quantum Mechanics

Classical experiments Principle of quantum mechanics Molecular orbital theory Molecular spectroscopy

Thermal electromagnetic radiation within or surrounding a body in thermodynamic equilibrium with its environment, or emitted by a blackbody

Glowing radiation caused by the heating up a a material i.e. Tungsten filament

A perfect absorber that is a substance that absorbs all frequencies of light and emits none; it would be black

Discrete units of light energy; the energy of a quantum was directly proportional to a frequency of an oscillator; E = hv

e- are mutter from a metal when the metal is irradiated with visible/ UV radiation

Below a given cutoff frequency of incident radiation, no e- were ejected from the metal surface, no matter how intense the radiation

Above the cutoff frequency, the # of e- emitted was directly proportional to the intensity of the radiation

As the frequency of the incident radiation increased, the maximum velocity of the ejected e- increased

Light particles

ha = 1/2•mv^2 + w, w = working energy, 1/2•mv^2 = kinetic energy of emitted electron

Light can be both a particle and a wave; wavelength = h/p = h/mv, p = momentum, h = Planck’s constant

6.626x10^-34 J/s

It is impossible to simultaneously measure the momentum and position of a particle such as an e-, because performing one measurement would disturb the particle and prevent the accurate measurement of the 2nd quantity

dq•dp > h/4pi; the product of the uncertainty of the position (dq) and the uncertainty of the momentum (dp) is greater than h/4pi

Has 5 postulates

The physical state of a particle can be fully described by a wave function of type x,y,z,t

The x,y,z,t wave functions are obtained by solving the appropriate schrodinger equation.

h^2/8pim• 💎^2¥ + [E-V(r)]¥ =0, 💎= laplacian operator in units m^-2 V = potential energy ¥ = position-space wave function m^-3/2 E = energy in J h = Planck's constant M = mass in kg

Every dynamic variable that correlates with a physically observable property is expressed as a linear operator

Operators that represent physical properties are derived from the classical expressions for these properties

The eigenvalues obtained by solving the appropriate schrodinger equation represent all possible values of an individual measurement of the quantity in question

Represented with a circumflex accent over the symbol that represents the variable in interest

A complex wave function used to describe the quantum mechanical state of a particle