### How to Draw Orbital Overlap Diagrams

```How to Draw Orbital Overlap
Diagrams
Science Learning Center
The Key
• Make sure that you follow
the exact same steps each
time.
• It’s too easy to miss
something if you do the
drawings with a different
order to the steps.
• You can change the order
from what we show you
here, but whatever order
you use, use the same
each tme.
Step 1
• Draw the atoms in the
same positions as the
Lewis Dot Structure.
• Example:
O
C
H
H
Step 2
• We’ll be focusing on all
the orbitals involved in
sigma bonds (the first
bond between atoms)
and lone pair electrons
first.
• Draw the s orbitals for H
and the hybrid orbitals for
all the other atoms.
• Remember that 2 groups
of electrons = sp, 3 grp =
sp2, 4 grp = sp3.
O
C
H
H
Step 3
• Label all the orbitals.
• Add electrons to all the
orbitals. Note that the
electrons should be
drawn as half arrows, not
as arrows like is shown
here. One should be
pointing up and one
should be pointing down.
• Add sigma symbol to all
the overlaps.
SP2
SP2
O
SP2
s
s
H
S
SP2
SP2
C
s
SP2
H
S
Step 4
•
•
•
•
•
Now we will deal with the pi bond. Pi
bonds are used to form any bond
beyond the first bond (so double and
triple). Recall the pi bonds are made
from p orbitals. Because the C and O
are sp2 hybridized, they each have a
p orbital that can be used to form the
pi bond.
Draw one p orbital for each atom
involved in the pi bond. Only label
one of the orbs, because there is only
one p on each atm.
Add electrons one pointing up to one
p orbital and one pointing down to
the other p orbital.
Show the connection by drawing a
line from lobe to lobe.
Add pi symbol to all the overlaps.
SP2
SP2
O
P
SP2
s
s
H
S
SP2
SP2
C
P
s
SP2
H
S
Step 5
• Draw the bond angle
between any three
consecutive atoms. The
angle is whatever
number goes with the
hybridization of the
central atom. In this
case, that is sp2 = 120
degrees.
SP2
SP2
O
P
SP2
s
s
H
S
SP2
SP2
C
P
s
SP2
H
S
```