Electromagnetic waves. Electronic transitions Vibrational fine structure.

Electromagnetic waves

Electronic transitions

Vibrational fine structure

Stretching and bending vibrational modes for a CH2 grouphttp://en.wikipedia.org/wiki/Infrared_spectroscopy

Normal vibrational modeshttp://upload.wikimedia.org/wikipedia/commons/9/9b/1D_normal_modes_%28280_kB%29.gif

H2O

CO2

Part of the rotational-vibrational spectrum of HCl Gas, showing the presence of P- and R- branches. Frequency is on the x-axis, and transmittance on the y-axis.

Kinetic techniques

Determination of Concentration by Spectroscopic Methods

• Beer’s Law

lcAI

I 010log

• Io = Intensity of incident light

• I = Intensity of transmitted light = molar extinction coefficient• l = path length of cell• c = concentration of sample

Quantitative aspect

When X = Y and [X] + [Y] is constant, Isosbestic points occur

Morse energy curve for a diatomic molecule

Morse curve

Anharmonic Oscillator Model for a Diatomic Molecule