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Table of Contents
Chapter 10 Pauling “3-Electron Bonds” and “Increased-Valence”
Theory for N 2 O 4 .............................................................. 131
10-1 Pauling “3-Electron Bonds” and “Increased-Valence” Structures for
N 2 O 4 .................................................................................................... 131
10-2 “Increased-Valence” Structures and Molecular Orbital Theory
for N 2 O 4 ............................................................................................... 132
10-3 “Increased-Valence” Theory and Configuration Interaction for N 2 O 4 ..... 134
10-4 Conclusions ......................................................................................... 136
References ...................................................................................................... 137
Chapter 11 Pauling “3-Electron Bonds” and “Increased-Valence”
Structures ....................................................................... 139
11-1 Pauling “3-Electron Bonds” and 4- Electron 3-Centre Bonding ............. 139
11-2 “Increased-Valence” or Electronic Hypervalence via Pauling
“3-Electron Bonds ............................................................................... 141
11-3 Nitrosyl Halides ................................................................................... 143
11-4 CH 3 NO and HNO................................................................................. 147
11-5 Some Dioxygenyl Compounds ............................................................. 148
11-6 Some S-O and S-S Compounds ............................................................ 149
11-7 O 3 , SO 2 , S 2 O and NO 2
– ......................................................................... 151
11-8 Pauling “3-Electron Bonds” and 6-Electron 4-Centre Bonding: N 2 O 2 ,
Cl 2 O 2 , S 2 O 2 and
2+
2 4
S I .......................................................................... 152
11-9 NO 2 ,
-
2
NO , ClO 2 ,
-
2
SO and SO 3 ........................................................... 155
11-10 N 2 O 4 , N 2 O 3 and FNO 2 .......................................................................... 158
11-11 sym NO 3 and asym N 2 O 4 ....................................................................... 160
11-12 Conclusions ......................................................................................... 161
References ...................................................................................................... 161
Chapter 12
Structures Constructed from
Lewis Structures: Delocalization of a Lone-Pair
Electron into a Vacant Bonding Orbital ........................ 163
References ...................................................................................................... 166
Chapter 13 “Increased-Valence” Structures for N-Centre
Bonding Units ................................................................. 167
13-1 N 2 O and some Isoelectronic Molecules and Ions with 4-Electron
3-Centre Bonding Units ........................................................................ 167
13-2 N 2 O 4 ,
2
2 4
C O

and (RNO) 2 , with 6-Electron 4-Centre Bonding Units .... 169
13-3 Comments on 6-Electron 4-Centre Bonding Units ................................. 171
13-4 Cyclic 6-Electron 4-Centre Bonding Units ............................................ 173
13-5 Branching 6-Electron 4-Centre Bonding Units ...................................... 175
13-6 6-Electron 5-Centre Bonding Units: C 3 O 2 , Succinimide, and Pyrrole ..... 177
“Increased-Valence”