Quantum Theory and the Electronic Structure of Atoms
Wave Properties
A wave is defined as a
continuously repeating change or
oscillation in matter or in a
physical field by which energy is
transmitted.
It is characterised by
- its wavelength –
- its frequency
- its amplitude
u  
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 1
Quantum Theory and the Electronic Structure of Atoms
Components of a Light Wave
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 2
Quantum Theory and the Electronic Structure of Atoms
Electromagnetic Spectrum
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 3
Quantum Theory and the Electronic Structure of Atoms
Photoelectric Effect
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 4
Quantum Theory and the Electronic Structure of Atoms
Line Spectra of Some Elements
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 5
Quantum Theory and the Electronic Structure of Atoms
Bohr Orbits
According to the Bohr Theory, the
electron in a hydrogen atom can only be
found in one of these orbits.
Each orbit has a specific energy value.
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 6
Quantum Theory and the Electronic Structure of Atoms
Line Spectra of Hydrogen
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 7
Quantum Theory and the Electronic Structure of Atoms
Electron Density Distribution
Dot density represents electron
density. Regions of high electron
density represent a high probability
of finding the electron in that region
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 8
Quantum Theory and the Electronic Structure of Atoms
Electron Spin
If a charged particle spins it will create a tiny
magnetic field. This is what electrons do. This spin
creates a split in atomic spectra of atoms.
In 1924, it was proved that electrons do spin. It was
observed that there is a 50-50 distribution of spin,
i.e. 50% of electrons spin in a clockwise manner,
and the other 50% in an anticlockwise manner.
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 9
Quantum Theory and the Electronic Structure of Atoms
Boundary Surface Diagram of Orbitals
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 10
Quantum Theory and the Electronic Structure of Atoms
Orbital Energies
Single-electron atoms
General Chemistry I CHM 111
Many-electron atoms
Dr Erdal Onurhan
Slide 11
Quantum Theory and the Electronic Structure of Atoms
The Aufbau Principle
Using this diagram, we can
distribute electrons among
orbitals in an atom.
Remember that there might
be exceptions in rare
instances.
General Chemistry I CHM 111
Dr Erdal Onurhan
Slide 12