Best Lewis Structure
The Lewis structure that is closest to your structure is determined.
The hybridization of the atoms in this idealized Lewis structure
is given in the table below.
Please note that your structure can't be well described by a single
Lewis structure, because of extensive delocalization.
Hybridization in the Best Lewis Structure
1. A bonding orbital for Si1-Si2 with 1.9376 electrons
__has 46.93% Si 1 character in a s0.32 p3 hybrid
__has 53.07% Si 2 character in a s0.22 p3 hybrid
2. A bonding orbital for Si1-Si4 with 1.7031 electrons
__has 55.30% Si 1 character in a s0.38 p3 hybrid
__has 44.70% Si 4 character in a s0.09 p3 hybrid
3. A bonding orbital for Si2-Si3 with 1.7499 electrons
__has 56.59% Si 2 character in a s0.31 p3 hybrid
__has 43.41% Si 3 character in a s0.21 p3 d0.05 hybrid
4. A bonding orbital for Si2-Si4 with 1.4799 electrons
__has 55.36% Si 2 character in a s0.33 p3 d0.05 hybrid
__has 44.64% Si 4 character in a s0.16 p3 d0.05 hybrid
25. A lone pair orbital for Si1 with 1.9680 electrons
__made from a sp0.26 hybrid
26. A lone pair orbital for Si1 with 0.4570 electrons
__made from a p3 d0.08 hybrid
27. A lone pair orbital for Si2 with 1.9436 electrons
__made from a sp0.33 hybrid
28. A lone pair orbital for Si3 with 1.9384 electrons
__made from a sp0.15 hybrid
29. A lone pair orbital for Si3 with 0.4921 electrons
__made from a s0.11 p3 d0.05 hybrid
30. A lone pair orbital for Si3 with 0.1510 electrons
__made from a s0.52 p3 d0.15 hybrid
31. A lone pair orbital for Si4 with 1.9103 electrons
__made from a sp0.13 hybrid
32. A lone pair orbital for Si4 with 0.1082 electrons
__made from a s0.17 p3 d0.05 hybrid
-With core pairs on:Si 1 Si 1 Si 1 Si 1 Si 1 Si 2 Si 2 Si 2 Si 2 Si 2 Si 3 Si 3 Si 3 Si 3 Si 3 Si 4 Si 4 Si 4 Si 4 Si 4 -
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Donor Acceptor Interactions in the Best Lewis Structure
The localized orbitals in your best Lewis structure
can interact strongly. A filled bonding or lone pair orbital can
act as a donor and an empty or filled bonding, antibonding, or
lone pair orbital can act as an acceptor. These
interactions can strengthen and weaken bonds. For example, a
lone pair donor->antibonding acceptor orbital interaction
will weaken the bond
associated with the antibonding orbital. Conversly, an interaction
with a bonding pair as the acceptor will strengthen the bond.
Strong electron delocalization in your best Lewis structure will
also show up as donor-acceptor interactions.
Interactions greater than 20 kJ/mol for bonding and lone pair
orbitals are listed below.
The interaction of bonding donor orbital, 1, for Si1-Si2 with
the bonding acceptor orbital, 4, for Si2-Si4 is 107. kJ/mol.
The interaction of bonding donor orbital, 1, for Si1-Si2 with
the second lone pair acceptor orbital, 29, for Si3 is 149. kJ/mol.
The interaction of bonding donor orbital, 1, for Si1-Si2 with
the third lone pair acceptor orbital, 30, for Si3 is 72.2 kJ/mol.
The interaction of bonding donor orbital, 1, for Si1-Si2 with
the second lone pair acceptor orbital, 32, for Si4 is 111. kJ/mol.
The interaction of bonding donor orbital, 1, for Si1-Si2 with
the antibonding acceptor orbital, 121, for Si1-Si2 is 177. kJ/mol.
The interaction of bonding donor orbital, 1, for Si1-Si2 with
the antibonding acceptor orbital, 122, for Si1-Si4 is 60.4 kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si4 with
the bonding acceptor orbital, 4, for Si2-Si4 is 141. kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si4 with
the second lone pair acceptor orbital, 29, for Si3 is 394. kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si4 with
the third lone pair acceptor orbital, 30, for Si3 is 104. kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si4 with
the second lone pair acceptor orbital, 32, for Si4 is 317. kJ/mol.
The interaction of bonding donor orbital, 2, for Si1-Si4 with
the antibonding acceptor orbital, 122, for Si1-Si4 is 221. kJ/mol.
The interaction of bonding donor orbital, 3, for Si2-Si3 with
the bonding acceptor orbital, 4, for Si2-Si4 is 1126 kJ/mol.
The interaction of bonding donor orbital, 3, for Si2-Si3 with
the third lone pair acceptor orbital, 30, for Si3 is 298. kJ/mol.
The interaction of bonding donor orbital, 3, for Si2-Si3 with
the antibonding acceptor orbital, 122, for Si1-Si4 is 32.7 kJ/mol.
The interaction of bonding donor orbital, 3, for Si2-Si3 with
the antibonding acceptor orbital, 123, for Si2-Si3 is 25.5 kJ/mol.
The interaction of bonding donor orbital, 3, for Si2-Si3 with
the antibonding acceptor orbital, 124, for Si2-Si4 is 24.9 kJ/mol.
The interaction of bonding donor orbital, 4, for Si2-Si4 with
the third lone pair acceptor orbital, 30, for Si3 is 99.2 kJ/mol.
The interaction of bonding donor orbital, 4, for Si2-Si4 with
the second lone pair acceptor orbital, 32, for Si4 is 134. kJ/mol.
The interaction of bonding donor orbital, 4, for Si2-Si4 with
the antibonding acceptor orbital, 122, for Si1-Si4 is 23.5 kJ/mol.
The interaction of bonding donor orbital, 4, for Si2-Si4 with
the antibonding acceptor orbital, 123, for Si2-Si3 is 25.6 kJ/mol.
The interaction of bonding donor orbital, 4, for Si2-Si4 with
the antibonding acceptor orbital, 124, for Si2-Si4 is 29.4 kJ/mol.
The interaction of lone pair donor orbital, 25, for Si1 with
the second lone pair acceptor orbital, 29, for Si3 is 90.4 kJ/mol.
The interaction of the second lone pair donor orbital, 26, for Si1 with
the bonding acceptor orbital, 4, for Si2-Si4 is 96.2 kJ/mol.
The interaction of the second lone pair donor orbital, 26, for Si1 with
the second lone pair acceptor orbital, 29, for Si3 is 345. kJ/mol.
The interaction of lone pair donor orbital, 27, for Si2 with
the second lone pair acceptor orbital, 32, for Si4 is 25.4 kJ/mol.
The interaction of lone pair donor orbital, 28, for Si3 with
the second lone pair acceptor orbital, 26, for Si1 is 191. kJ/mol.
The interaction of lone pair donor orbital, 28, for Si3 with
the second lone pair acceptor orbital, 29, for Si3 is 191. kJ/mol.
The interaction of lone pair donor orbital, 28, for Si3 with
the third lone pair acceptor orbital, 30, for Si3 is 35.8 kJ/mol.
The interaction of lone pair donor orbital, 28, for Si3 with
the second lone pair acceptor orbital, 32, for Si4 is 132. kJ/mol.
The interaction of the second lone pair donor orbital, 29, for Si3 with
the third lone pair acceptor orbital, 30, for Si3 is 116. kJ/mol.
The interaction of the second lone pair donor orbital, 29, for Si3 with
the second lone pair acceptor orbital, 32, for Si4 is 91.4 kJ/mol.
The interaction of the third lone pair donor orbital, 30, for Si3 with
the second lone pair acceptor orbital, 32, for Si4 is 793. kJ/mol.
The interaction of lone pair donor orbital, 31, for Si4 with
the bonding acceptor orbital, 4, for Si2-Si4 is 131. kJ/mol.
The interaction of lone pair donor orbital, 31, for Si4 with
the second lone pair acceptor orbital, 26, for Si1 is 43.8 kJ/mol.
The interaction of lone pair donor orbital, 31, for Si4 with
the third lone pair acceptor orbital, 30, for Si3 is 263. kJ/mol.
The interaction of lone pair donor orbital, 31, for Si4 with
the second lone pair acceptor orbital, 32, for Si4 is 125. kJ/mol.
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Molecular Orbital Energies
The orbital energies are given in eV, where 1 eV=96.49 kJ/mol.
Orbitals with very low energy are core 1s orbitals.
More antibonding orbitals than you might expect are sometimes
listed, because d orbitals are always included for heavy
atoms and p orbitals are included for H atoms.
Up spins are shown with a ^ and down spins are shown as v.
32 ----- -1.320 31 ----- -1.322
30 ----- -5.248 29 ----- -5.250
28 -^-v- -5.682 27 -^-v- -5.682 26 -^-v- -5.685
25 -^-v- -6.405
24 -^-v- -10.59 23 -^-v- -10.60 22 -^-v- -10.60
21 -^-v- -15.61
20 -^-v- -95.10 19 -^-v- -95.10 18 -^-v- -95.10
17 -^-v- -95.11
16 -^-v- -95.19 15 -^-v- -95.20 14 -^-v- -95.20 13 -^-v- -95.20 12 -^-v- -95.20 11 -^-v- -95.20 10 -^-v- -95.21 9 -^-v- -95.21
8 -^-v- -137.5 7 -^-v- -137.5 6 -^-v- -137.5 5 -^-v- -137.5
4 -^-v- -1773. 3 -^-v- -1773. 2 -^-v- -1773. 1 -^-v- -1773.
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Total Electronic Energy
The total electronic energy is a very large number, so by convention
the units are given in atomic units, that is Hartrees (H). One
Hartree is 2625.5 kJ/mol. The energy reference is for totally
dissociated atoms. In other words, the reference state is a gas
consisting of nuclei and electrons all at infinite distance from
each other. The electronic energy includes all electric
interactions and the kinetic energy of the electrons. This energy
does not include translation, rotation, or vibration of the
the molecule.
Total electronic energy = -1157.9149459467 Hartrees
* Also check the planar conformer
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