Si2O, cyclic

SI3
| \
O1 - SI2
Tell me about the atomic charges, dipole moment, bond lengths, angles, bond orders,
molecular orbital energies, or total energy.
Tell me about the best Lewis structure.

Atomic Charges and Dipole Moment

O1 charge=-0.319
SI2 charge= 0.155
SI3 charge= 0.163
with a dipole moment of 1.26608 Debye

Bond Lengths:

between O1 and SI2: distance=1.738 ang___ between O1 and SI3: distance=1.738 ang___
between SI2 and SI3: distance=2.378 ang___

Bond Angles:

for SI3-O1-SI2: angle=86.33 deg___

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Bond Orders (Mulliken):

between O1 and SI2: order=0.570___ between O1 and SI3: order=0.569___
between SI2 and SI3: order=1.241___

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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 O1-Si2 with 1.9955 electrons
__has 88.56% O 1 character in a sp2.69 hybrid
__has 11.44% Si 2 character in a s0.30 p3 d0.09 hybrid

2. A bonding orbital for O1-Si3 with 1.9955 electrons
__has 88.56% O 1 character in a sp2.70 hybrid
__has 11.44% Si 3 character in a s0.30 p3 d0.09 hybrid

3. A bonding orbital for Si2-Si3 with 1.9931 electrons
__has 49.99% Si 2 character in a s0.19 p3 hybrid
__has 50.01% Si 3 character in a s0.19 p3 hybrid

15. A lone pair orbital for O1 with 1.9896 electrons
__made from a sp1.15 hybrid

16. A lone pair orbital for O1 with 1.7857 electrons
__made from a p-pi orbital ( 99.91% p 0.09% d)

17. A lone pair orbital for Si2 with 1.9881 electrons
__made from a sp0.16 hybrid

18. A lone pair orbital for Si2 with 0.1072 electrons
__made from a p-pi orbital ( 94.10% p 5.90% d)

19. A lone pair orbital for Si3 with 1.9881 electrons
__made from a sp0.16 hybrid

20. A lone pair orbital for Si3 with 0.1072 electrons
__made from a p-pi orbital ( 94.10% p 5.90% d)

-With core pairs on: O 1 Si 2 Si 2 Si 2 Si 2 Si 2 Si 3 Si 3 Si 3 Si 3 Si 3 -

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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 the second lone pair donor orbital, 16, for O1 with the second lone pair acceptor orbital, 18, for Si2 is 166. kJ/mol.

The interaction of the second lone pair donor orbital, 16, for O1 with the second lone pair acceptor orbital, 20, for Si3 is 166. kJ/mol.

The interaction of lone pair donor orbital, 17, for Si2 with the antibonding acceptor orbital, 85, for O1-Si3 is 23.1 kJ/mol.

The interaction of lone pair donor orbital, 19, for Si3 with the antibonding acceptor orbital, 84, for O1-Si2 is 23.1 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.

22 ----- -1.102

21 ----- -1.374


20 ----- -3.104

19 ----- -3.875

18 -^-v- -4.695


17 -^-v- -7.414

16 -^-v- -8.234


15 -^-v- -9.569


14 -^-v- -12.11
13 -^-v- -12.13


12 -^-v- -24.76


11 -^-v- -94.97
10 -^-v- -94.98

9 -^-v- -95.10 8 -^-v- -95.10

7 -^-v- -95.38 6 -^-v- -95.39


5 -^-v- -137.5 4 -^-v- -137.5


3 -^-v- -507.4


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 = -654.2647721268 Hartrees

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