Supplemental Materials 1. Structural parameters for selected nonmetal oxides.
Octet
rule
AO2
A = N or P
N2 O4
N2 O3
AO2
A = O or S
Formal
charge
Octet
rule
SO3
ClO
ClO2
Formal
charge
Supplemental Materials 2a. Structural parameters for selected nitrogen halides and oxohalides.
Octet
rule
ONF3
Formal
charge
Octet
rule
O2NX
Formal
charge
Supplemental Materials 2b. Structural parameters for selected halides and oxohalides with Period 3
central atoms.
Octet
rule
Formal
charge
Octet
rule
PX5
OAX3
A = N or P
SX4
O2SX2
SX6
O3ClX
ClX3
O2PCl
Formal
charge
Supplemental Materials 3. Structural parameters for selected nonmetal oxoacids and oxoanions.
Octet
rule
Formal
charge
Octet
rule
HNO3
SO42-
NO3HClO4
H2SO4
ClO4-
HSO4ClO3-
Formal
charge
Supplemental Materials 4. Structural parameters for Group 13 halides and tetrahalide anions.
Octet
rule
Formal
charge
Brown’s BVM conception of
AX3 and AX4- species.
AX3
A = B or Al
X = F or Cl
AX4–
A = B or Al
X = F or Cl
AX
3
AX4
-
Supplemental Materials 5 – Systematic drawing of Lewis structures.
Lewis structures can be drawn using a systematic, step-by-step approach, as is illustrated below
for SO2 (the adjustments required for binary molecules are well known, and so it will not be
discussed here). The difference between the octet rule and formal charge systems comes at the
end of the usual procedure, when multiple bonds are added.
Step 1: Sum the valence electrons.
(6 valence e– from S) + 2 x ((6 valence e– from O) = 18 valence electrons
Step 2: Determine the central atom. – sulfur (lower electronegativity)
Step 3: Draw skeletal structure, connecting central atom to each terminal atom with one bond.
Step 4: Place 6 electrons (3 lone pairs) around every terminal, non-hydrogen atom.
Step 5: Place any remaining electrons on central atom.
Step 6a: Octet rule system only – Convert terminal atom lone pairs to bond pairs until central
atom has 8 (or 7, for radicals) valence electrons.
Step 6b: Formal charge system only – convert additional terminal atom lone pairs to bond pairs
until formal charges are minimized (all zero for neutral molecules).
Supplemental Materials 6. Lewis
structures of the Group 13 halides (left)
and tetrahalide anions (right).
Octet
rule
Formal charge
BVM
conception
Supplemental Materials 7. Bonding in ONF3.
..
: F:
..
: F:
..
..
:O
N
F
..
.. :
..
:F
.. :
..
..
:
:O
N
F
..
.. :
:F
.. :
..
:F
.. :
..
:O
.. N
:F
.. :
..
F
.. :
..
: F:
..
:O
.. N
.
:
F
.
.
:F
.. :
ONF3 – 4 resonance structures, N-F bond order ~0.75, N-O bond
order ~1.75, total bonding at nitrogen < 4
..
O
..
..
: F:
P
:F
.:
.
..
F
.. :
OPF3 – 1 structure, P-F bond order ~ 1.0,
P-O bond order ~ 2.0, total bonding at
phosphorus ~ 5