Optical Spectroscopy

What does sign nu (ν) represent?

Frequency

What does sign nu tilde (ṽ) represent?

Wavenumber

An ideal emitter

At all freq.s emits the same amount of or more radiation than any other body at the same temperature.

A diffuse emitter

Emits the same amount of radiation in all directions.

A blackbody emitter is

Ideal and diffuse

Standing wave requirements in a 1D cavity:

v(nu) = nc/2L

Standing wave requirements in a 3D cavity:

n(x)²+n(y)²+n(z)² = 4L²v(nu)²/c²

Total number of allowed modes per unit volume per frequency (number of antinodes in standing wave)

8πv(nu)²/c³

Rayleigh-Jeans Law

energy per unit volume per frequency = 8πv(nu)²/c³ * kT

What does kT represent in Rayleigh-Jeans Law

Energy per mode/energy level

Stopping voltage is

a property of the metal

Planck-Einstein Relation

E=hv(nu)

de Broglie wavelength equation

λ = h/mv(nu)

de Broglie wavelength represents

the length scale at which its wave-like properties are important

Microwave radiation causes

rotational spectroscopy

Infra-red radiation causes

vibrational spectroscopy

Spectroscopy definition

the study of the interaction of EM radiation with matter

Peak intensity is determined by

Population, transition probability, state degeneracy, path length of sample

Heisenberg uncertainty equation

ΔEΔt >=h/2π, t is time spent in excited state

Natural linewidth is

the limit to how narrow spectral lines can be.

In order for an atom or molecule to absorb/emit a photon at a specific frequency,

it must possess a dipole oscillating at that frequency.

Beer-Lambert Law

A = εLc

A =

log(I0/I), I=intensity

ln(I0/I) =

σLc = αL, σ=absorption cross-section, α=absorption coefficient

T (transmittance)=

I/I0