## 2-methylbutane radical cation, CH3CH(CH3)CH2CH3+• or (CH3)2CHCH2CH3+•

 H15 H16 H4 | / | H14 - C13 H6 - C3 - H5 \ / H12 C1 - C2 | / | | \ H10 - C9 H17 H7 H8 \ H11
The ion charge is 1. The multiplicity is 2.

## Atomic Charges and Dipole Moment

C1 charge= 0.263
C2 charge=-0.019
C3 charge=-0.430
H4 charge= 0.180
H5 charge= 0.230
H6 charge= 0.182
H7 charge= 0.161
H8 charge= 0.143
C9 charge=-0.722
H10 charge= 0.287
H11 charge= 0.233
H12 charge= 0.250
C13 charge=-0.560
H14 charge= 0.241
H15 charge= 0.224
H16 charge= 0.192
H17 charge= 0.142
with a dipole moment of 2.66009 Debye

## Bond Lengths:

between C1 and C2: distance=1.934 ang___ between C1 and C9: distance=1.492 ang___
between C1 and C13: distance=1.490 ang___ between C1 and H17: distance=1.108 ang___
between C2 and C3: distance=1.479 ang___ between C2 and H7: distance=1.102 ang___
between C2 and H8: distance=1.100 ang___ between C2 and C13: distance=2.762 ang___
between C3 and H4: distance=1.101 ang___ between C3 and H5: distance=1.123 ang___
between C3 and H6: distance=1.105 ang___ between C3 and C13: distance=3.196 ang___
between C9 and H10: distance=1.119 ang___ between C9 and H11: distance=1.103 ang___
between C9 and H12: distance=1.104 ang___ between C9 and C13: distance=2.571 ang___
between C13 and H14: distance=1.118 ang___ between C13 and H15: distance=1.106 ang___
between C13 and H16: distance=1.101 ang___

## Bond Angles:

for C3-C2-C1: angle=111.8 deg___ for H4-C3-C2: angle=114.7 deg___
for H5-C3-C2: angle=104.7 deg___ for H6-C3-C2: angle=114.4 deg___
for H7-C2-C1: angle=95.89 deg___ for H8-C2-C1: angle=97.01 deg___
for C9-C1-C2: angle=104.6 deg___ for H10-C9-C1: angle=106.2 deg___
for H11-C9-C1: angle=114.0 deg___ for H12-C9-C1: angle=113.7 deg___
for C13-C1-C2: angle=106.7 deg___ for H14-C13-C1: angle=106.3 deg___
for H15-C13-C1: angle=113.6 deg___ for H16-C13-C1: angle=113.9 deg___
for H17-C1-C2: angle=91.37 deg___

## Bond Orders (Mulliken):

between C1 and C2: order=0.248___ between C1 and C9: order=0.837___
between C1 and C13: order=0.983___ between C1 and H17: order=0.916___
between C2 and C3: order=0.790___ between C2 and H7: order=0.936___
between C2 and H8: order=0.949___ between C2 and C13: order=-0.115___
between C3 and H4: order=0.957___ between C3 and H5: order=0.955___
between C3 and H6: order=0.940___ between C3 and C13: order=0.077___
between C9 and H10: order=0.966___ between C9 and H11: order=0.967___
between C9 and H12: order=0.919___ between C9 and C13: order=-0.147___
between C13 and H14: order=0.925___ between C13 and H15: order=0.938___
between C13 and H16: order=0.960___

## 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. The Lewis structure is built for the up and down electrons, separately. Note that the up and down structures can be very different.

### Hybridization in the Best Lewis Structure

#### Down Electrons

1. A bonding orbital for C1-C2 with 0.9821 electrons
__has 47.14% C 1 character in a s0.41 p3 hybrid
__has 52.86% C 2 character in a s0.51 p3 hybrid

2. A bonding orbital for C1-C9 with 0.9957 electrons
__has 51.46% C 1 character in a sp2.10 hybrid
__has 48.54% C 9 character in a sp2.30 hybrid

3. A bonding orbital for C1-C13 with 0.9960 electrons
__has 51.33% C 1 character in a sp2.11 hybrid
__has 48.67% C13 character in a sp2.29 hybrid

4. A bonding orbital for C1-H17 with 0.9888 electrons
__has 61.00% C 1 character in a s0.94 p3 hybrid
__has 39.00% H17 character in a s orbital

5. A bonding orbital for C2-C3 with 0.9980 electrons
__has 51.27% C 2 character in a sp1.94 hybrid
__has 48.73% C 3 character in a sp2.33 hybrid

6. A bonding orbital for C2-H7 with 0.9943 electrons
__has 61.21% C 2 character in a sp2.90 hybrid
__has 38.79% H 7 character in a s orbital

7. A bonding orbital for C2-H8 with 0.9936 electrons
__has 61.25% C 2 character in a sp2.83 hybrid
__has 38.75% H 8 character in a s orbital

8. A bonding orbital for C3-H4 with 0.9949 electrons
__has 61.34% C 3 character in a sp2.97 hybrid
__has 38.66% H 4 character in a s orbital

9. A bonding orbital for C3-H5 with 0.9878 electrons
__has 60.82% C 3 character in a s0.77 p3 hybrid
__has 39.18% H 5 character in a s orbital

10. A bonding orbital for C3-H6 with 0.9945 electrons
__has 61.18% C 3 character in a s0.97 p3 hybrid
__has 38.82% H 6 character in a s orbital

11. A bonding orbital for C9-H10 with 0.9881 electrons
__has 60.80% C 9 character in a s0.79 p3 hybrid
__has 39.20% H10 character in a s orbital

12. A bonding orbital for C9-H11 with 0.9939 electrons
__has 61.20% C 9 character in a s0.96 p3 hybrid
__has 38.80% H11 character in a s orbital

13. A bonding orbital for C9-H12 with 0.9947 electrons
__has 61.26% C 9 character in a s0.97 p3 hybrid
__has 38.74% H12 character in a s orbital

14. A bonding orbital for C13-H14 with 0.9879 electrons
__has 60.77% C13 character in a s0.79 p3 hybrid
__has 39.23% H14 character in a s orbital

15. A bonding orbital for C13-H15 with 0.9944 electrons
__has 61.15% C13 character in a s0.96 p3 hybrid
__has 38.85% H15 character in a s orbital

16. A bonding orbital for C13-H16 with 0.9938 electrons
__has 61.33% C13 character in a s0.98 p3 hybrid
__has 38.67% H16 character in a s orbital

-With core pairs on: C 1 C 2 C 3 C 9 C13 -

#### Up Electrons

1. A bonding orbital for C1-C9 with 0.9926 electrons
__has 50.60% C 1 character in a sp1.85 hybrid
__has 49.40% C 9 character in a sp2.30 hybrid

2. A bonding orbital for C1-C13 with 0.9925 electrons
__has 50.50% C 1 character in a sp1.85 hybrid
__has 49.50% C13 character in a sp2.30 hybrid

3. A bonding orbital for C1-H17 with 0.9772 electrons
__has 61.24% C 1 character in a sp2.38 hybrid
__has 38.76% H17 character in a s orbital

4. A bonding orbital for C2-C3 with 0.9949 electrons
__has 49.99% C 2 character in a sp1.70 hybrid
__has 50.01% C 3 character in a sp2.33 hybrid

5. A bonding orbital for C2-H7 with 0.9840 electrons
__has 60.69% C 2 character in a sp2.19 hybrid
__has 39.31% H 7 character in a s orbital

6. A bonding orbital for C2-H8 with 0.9873 electrons
__has 60.27% C 2 character in a sp2.23 hybrid
__has 39.73% H 8 character in a s orbital

7. A bonding orbital for C3-H4 with 0.9937 electrons
__has 61.64% C 3 character in a s0.98 p3 hybrid
__has 38.36% H 4 character in a s orbital

8. A bonding orbital for C3-H5 with 0.9514 electrons
__has 63.92% C 3 character in a s0.81 p3 hybrid
__has 36.08% H 5 character in a s orbital

9. A bonding orbital for C3-H6 with 0.9900 electrons
__has 61.90% C 3 character in a s0.94 p3 hybrid
__has 38.10% H 6 character in a s orbital

10. A bonding orbital for C9-H10 with 0.9573 electrons
__has 63.65% C 9 character in a s0.84 p3 hybrid
__has 36.35% H10 character in a s orbital

11. A bonding orbital for C9-H11 with 0.9908 electrons
__has 61.61% C 9 character in a s0.94 p3 hybrid
__has 38.39% H11 character in a s orbital

12. A bonding orbital for C9-H12 with 0.9932 electrons
__has 61.60% C 9 character in a s0.95 p3 hybrid
__has 38.40% H12 character in a s orbital

13. A bonding orbital for C13-H14 with 0.9561 electrons
__has 63.82% C13 character in a s0.84 p3 hybrid
__has 36.18% H14 character in a s orbital

14. A bonding orbital for C13-H15 with 0.9912 electrons
__has 61.71% C13 character in a s0.93 p3 hybrid
__has 38.29% H15 character in a s orbital

15. A bonding orbital for C13-H16 with 0.9923 electrons
__has 61.62% C13 character in a s0.95 p3 hybrid
__has 38.38% H16 character in a s orbital

21. A lone pair orbital for C1 with 0.1152 electrons

-With core pairs on: C 1 C 2 C 3 C 9 C13 -

#### 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, 10, for C9-H10 with the lone pair acceptor orbital, 21, for C1 is 67.0 kJ/mol.

The interaction of bonding donor orbital, 13, for C13-H14 with the lone pair acceptor orbital, 21, for C1 is 69.1 kJ/mol.

The interaction of bonding donor orbital, 1, for C1-C9 with the lone pair acceptor orbital, 22, for C2 is 18.8 kJ/mol.

The interaction of bonding donor orbital, 2, for C1-C13 with the lone pair acceptor orbital, 22, for C2 is 20.8 kJ/mol.

The interaction of bonding donor orbital, 3, for C1-H17 with the lone pair acceptor orbital, 22, for C2 is 45.8 kJ/mol.

The interaction of lone pair donor orbital, 21, for C1 with the lone pair acceptor orbital, 22, for C2 is 865. kJ/mol.

The interaction of bonding donor orbital, 4, for C2-C3 with the lone pair acceptor orbital, 21, for C1 is 19.9 kJ/mol.

The interaction of bonding donor orbital, 5, for C2-H7 with the lone pair acceptor orbital, 21, for C1 is 42.6 kJ/mol.

The interaction of bonding donor orbital, 6, for C2-H8 with the lone pair acceptor orbital, 21, for C1 is 31.5 kJ/mol.

The interaction of bonding donor orbital, 8, for C3-H5 with the lone pair acceptor orbital, 22, for C2 is 77.0 kJ/mol.

## 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. Only the spin up electron orbital energies are given.

25 ----- -2.806

24 ----- -3.061

23 ----- -3.735

22 ----- -5.762

21 -^--- -12.10

20 -^-v- -13.79
19 -^-v- -13.83

18 -^-v- -14.00

17 -^-v- -14.36

16 -^-v- -14.70

15 -^-v- -15.07

14 -^-v- -15.74

13 -^-v- -16.19

12 -^-v- -16.48

11 -^-v- -17.11

10 -^-v- -19.30

9 -^-v- -20.61

8 -^-v- -22.30

7 -^-v- -24.09

6 -^-v- -25.62

5 -^-v- -271.3 4 -^-v- -271.3
3 -^-v- -271.4

2 -^-v- -273.2

1 -^-v- -273.4

## 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 = -197.4658767219 Hartrees