(CH3)2CH=CH2, 2-methylpropene

H7H8
\ /
C6H3
/ \ /
H9C1 - C2
// | \
H12 - C10H5H4
\
H11
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

C1 charge= 0.492
C2 charge=-0.589
H3 charge= 0.157
H4 charge= 0.160
H5 charge= 0.157
C6 charge=-0.499
H7 charge= 0.136
H8 charge= 0.134
H9 charge= 0.136
C10 charge=-0.770
H11 charge= 0.238
H12 charge= 0.243
with a dipole moment of 0.64912 Debye

Bond Lengths:

between C1 and C2: distance=1.513 ang___ between C1 and H4: distance=2.181 ang___
between C1 and C6: distance=1.524 ang___ between C1 and H8: distance=2.188 ang___
between C1 and C10: distance=1.347 ang___ between C2 and H3: distance=1.107 ang___
between C2 and H4: distance=1.103 ang___ between C2 and H5: distance=1.107 ang___
between C2 and C10: distance=2.502 ang___ between C6 and H7: distance=1.105 ang___
between C6 and H8: distance=1.104 ang___ between C6 and H9: distance=1.105 ang___
between C10 and H11: distance=1.096 ang___ between C10 and H12: distance=1.097 ang___

Bond Angles:

for H3-C2-C1: angle=110.6 deg___ for H4-C2-C1: angle=112.0 deg___
for H5-C2-C1: angle=110.8 deg___ for C6-C1-C2: angle=116.1 deg___
for H7-C6-C1: angle=111.1 deg___ for H8-C6-C1: angle=111.7 deg___
for H9-C6-C1: angle=111.2 deg___ for C10-C1-C2: angle=121.9 deg___
for H11-C10-C1: angle=121.4 deg___ for H12-C10-C1: angle=121.6 deg___

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Bond Orders (Mulliken):

between C1 and C2: order=0.648___ between C1 and H4: order=-0.131___
between C1 and C6: order=0.656___ between C1 and H8: order=-0.077___
between C1 and C10: order=1.837___ between C2 and H3: order=0.971___
between C2 and H4: order=1.058___ between C2 and H5: order=0.971___
between C2 and C10: order=0.161___ between C6 and H7: order=0.989___
between C6 and H8: order=1.027___ between C6 and H9: order=0.989___
between C10 and H11: order=0.958___ between C10 and H12: order=0.977___

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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.

Hybridization in the Best Lewis Structure

1. A bonding orbital for C1-C2 with 1.9868 electrons
__has 49.76% C 1 character in a sp2.22 hybrid
__has 50.24% C 2 character in a sp2.29 hybrid

2. A bonding orbital for C1-C6 with 1.9862 electrons
__has 49.71% C 1 character in a sp2.28 hybrid
__has 50.29% C 6 character in a sp2.32 hybrid

3. A bonding orbital for C1-C10 with 1.9903 electrons
__has 51.48% C 1 character in a sp1.59 hybrid
__has 48.52% C10 character in a sp1.48 hybrid

4. A bonding orbital for C1-C10 with 1.9706 electrons
__has 46.33% C 1 character in a p-pi orbital ( 99.85% p 0.15% d)
__has 53.67% C10 character in a p-pi orbital ( 99.86% p 0.14% d)

5. A bonding orbital for C2-H3 with 1.9830 electrons
__has 59.42% C 2 character in a s0.89 p3 hybrid
__has 40.58% H 3 character in a s orbital

6. A bonding orbital for C2-H4 with 1.9909 electrons
__has 59.58% C 2 character in a s0.94 p3 hybrid
__has 40.42% H 4 character in a s orbital

7. A bonding orbital for C2-H5 with 1.9831 electrons
__has 59.42% C 2 character in a s0.89 p3 hybrid
__has 40.58% H 5 character in a s orbital

8. A bonding orbital for C6-H7 with 1.9855 electrons
__has 59.90% C 6 character in a s0.90 p3 hybrid
__has 40.10% H 7 character in a s orbital

9. A bonding orbital for C6-H8 with 1.9921 electrons
__has 59.33% C 6 character in a s0.92 p3 hybrid
__has 40.67% H 8 character in a s orbital

10. A bonding orbital for C6-H9 with 1.9856 electrons
__has 59.90% C 6 character in a s0.91 p3 hybrid
__has 40.10% H 9 character in a s orbital

11. A bonding orbital for C10-H11 with 1.9858 electrons
__has 59.07% C10 character in a sp2.33 hybrid
__has 40.93% H11 character in a s orbital

12. A bonding orbital for C10-H12 with 1.9857 electrons
__has 59.00% C10 character in a sp2.35 hybrid
__has 41.00% H12 character in a s orbital

-With core pairs on: C 1 C 2 C 6 C10 -

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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, 5, for C2-H3 with the second antibonding acceptor orbital, 136, for C1-C10 is 21.6 kJ/mol.

The interaction of bonding donor orbital, 6, for C2-H4 with the antibonding acceptor orbital, 134, for C1-C6 is 24.5 kJ/mol.

The interaction of bonding donor orbital, 7, for C2-H5 with the second antibonding acceptor orbital, 136, for C1-C10 is 21.5 kJ/mol.

The interaction of bonding donor orbital, 9, for C6-H8 with the antibonding acceptor orbital, 135, for C1-C10 is 22.1 kJ/mol.

The interaction of bonding donor orbital, 11, for C10-H11 with the antibonding acceptor orbital, 134, for C1-C6 is 37.5 kJ/mol.

The interaction of bonding donor orbital, 12, for C10-H12 with the antibonding acceptor orbital, 133, for C1-C2 is 37.1 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.

20 ----- 2.301

19 ----- 2.004

18 ----- 1.704


17 ----- -0.786


16 -^-v- -5.897


15 -^-v- -8.141

14 -^-v- -8.794
13 -^-v- -8.832

12 -^-v- -9.391


11 -^-v- -10.44

10 -^-v- -10.81

9 -^-v- -10.98


8 -^-v- -12.68


7 -^-v- -16.49

6 -^-v- -16.89


5 -^-v- -19.72


4 -^-v- -265.7

3 -^-v- -266.1 2 -^-v- -266.1

1 -^-v- -266.6

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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 = -157.2667402446 Hartrees

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