Chemistry Reference
In-Depth Information
Table 11.1 Energies and coefficients of the atomic orbitals contributions to the molecular orbitals
of ethene and butadiene
Hydrocarbon
K
ε
c 1
c 2
c 3
c 4
1
2
1
2
C 2 H 4
1.0000
ε 1 = ε HOMO = α + β
-
-
1
2
1
2
1.0000
ε 2 = ε LUMO = α − β
-
-
C 4 H 6
1.6180
ε 1 = α +
1.6180
β
0.3717
0.6015
0.6015
0.3717
0.6180
ε 2 = ε HOMO = α +
0.6180
β
0.6015
0.3717
0.3717
0.6015
0.6180
ε
= ε
= α −
0.6180
β
0.6015
0.3717
0.3717
0.6015
3
LUMO
1.6180
ε 4 = α −
1.6180
β
0.3717
0.6015
0.6015
0.3717
Fig. 11.1 Energetic diagrams for ethene ( a ) and butadiene ( b )
Table 11.2 Absolute bonding energies in kcal/mol (
18 kcal/mol) for the Hückel orbital
HOMO- like levels for molecules of Table 11.1 , along the related bondonic radii of action, mass
ratio respecting the electronic unit, and the bondonic gravitational ratio respecting the universal
gravitational unit, according with Eqs. ( 11.37a , 11.37b , 11.37c ), respectively
Hydrocarbon
α =
0,
β =−
10 6
10 53
E bond ( kcal/mol )
X B (Å)
ς m ×
ς G ×
C 2 H 4
ε 1 = ε HOMO =− 18
201.174
120.607
246.591
C 4 H 6
ε 1 =−
29.124
124.335
195.142
94.1932
ε 2 = ε HOMO =−
11.124
325.525
74.5352
645.654
￿
The bondonic radii and gravitational actions are parallel increasing, while some-
how anti-parallel with the bondonic mass variation as the bonding energy
decreases from more to less bonding nature, i.e. from inner molecular orbital
to the frontier HOMO;
￿
For larger system the HOMO level is less bound so having less bondonic mass
and higher radius of action that determine also a higher gravitational influence (in
order to keep the bond to a longer range of action).
 
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