Module 5 Flashcards
Orbital Overlap
Bond formation.
σ Bond
When 2 atoms are covalently bonded. Orbitals overlap on-axis (ie. along the internuclear axis (INA)). Are much more effective than π overlap (are stronger). Often involves overlap of hybrid orbitals.
π Bond
Orbitals overlap off-axis (not on INA). Are associated with sideways overlap of orbitals. Arise only with double and triple bonds. Usually unhybridized p orbitals. Always accompany a σ bond.
Orbital Hybridization
Take “n” atomic orbitals and mix them to generate “n” hybrid orbitals.
sp
50% s and 50% p. 2 hybridized and 2 unhybridized orbitals.
sp2
33% s and 67% p. 3 hybridized and 1 unhybridized orbitals.
sp3
25% s and 75% p. 4 hybridized orbitals.
Interior Atom
An atom that is bonded to more than one other atom.
Molecular Orbital Theory (MO Theory)
Tells us how a single electron interacts with all of the nuclei.
Valence Bond Theory (VB Theory)
Describes the bonds between two atoms.
Core Electrons
Electrons that are not valence electrons.
LCAO
Linear combination of atomic orbitals.
LCAO-MO Method
The molecular orbitals (MOs) are obtained by taking appropriate combinations of the atomic orbitals (AOs). From AO to MO.
Antibonding MO
Are higher in energy than the original AO and have a node that cuts the internuclear axis.
Bonding MO
Are lower in energy than the original AO and do not have a node that cuts the internuclear axis.
