Chapter 5

Electromagnetic energy (light)

Characterized by wavelength, frequency, and amplitude

• Quantized

Wavelength (\lambda)

Distance between successive wave peaks

Frequency (\nu)

Number of wave peaks that pass a given point per unit time

Amplitude

Height of the wave maximum from the center

Speed of light (c)

3.00\cdot10^8\frac{m}{s}

Diffraction

Bending of waves around an object

Constructive and destructive interference

Wave properties

Photoelectric effect

Irradiation of a clean metal surface with light causes electrons to be ejected from the metal. The frequency of light used for irradiation must be above some threshold value with is different for every metal

Planck’s constant (h)

6.626\cdot10^{-34}Js

Energy (E)

E = h\nu

Line spectrum

Series of discrete lines on an otherwise dark background as a result of light emitted by an excited atom

m

Shell the transition is to (inner shell)

n

Shell the transition is from (outer shell)

Wave function

\psi

Probability density

\psi^2

Quantum numbers

n, l, ml

• Characterizes a wave function by three parameters

Principal quantum number (n)

• Describes size and energy level of orbital

• Aka shell

• Positive integer

Angular-momentum quantum number (l)

• Defines the 3D shape of the orbital

• Aka subshelll

• Integers ranging from 0 to (n - 1)

• Types of orbitals: s, p, d, f