calculation of dihedral angle using different basises

Calculation of Dihedral Angle Using different Basises

Dihedral angle

• The angle created by two intersecting planes

Importance of dihedral angle Conformation

Molecule of InterestC14H20N2

1. Change in dihedral angle

Minimal basis HF

139.95

6-21 G HF

120.60

6-31G* HF

116.34

6-31G** HF116.11

6-31+G* HF

118.50

Comparison

Basis set

Dihedral angle

139.95116.11

Minimal basis HF 6-31G**

Minimal basis 6-31G**

HOMO

LUMO

Minimal basis 6-31G**

Density distribution on HOMO and LUMO

HOMO

LUMO

2.HOMO LUMO ENERGY GAP

Dihedral Angle

Energy Gap (eV)

Conclusions

1. Dihedral angle became defined with better basis sets.

2. Change in dihedral angle effects the HOMO - LUMO gap of the molecule.

Reference1.http://www.structuralbioinformatics.com/chapter7.shtml

2.http://www.cartage.org.lb/en/themes/Sciences/Chemistry/Org anicchemistry/Common/Common.htm.

3. Organic Chemistry, William H. Brown, Christopher S., Foote 3. Organic Chemistry, William H. Brown, Christopher S., Foote Brent L. IversonBrent L. Iverson

4. A brief guide to Molecular Mechanics and Quantum Chemical 4. A brief guide to Molecular Mechanics and Quantum Chemical calculations , warren J. Hehre, Jianguo Yu, Philip E. calculations , warren J. Hehre, Jianguo Yu, Philip E.

Klunzinger, Liang Lou.Klunzinger, Liang Lou.