Quantum chemical calculations of nicotine and caffeine molecule in gas phase and solvent using DFT methods
Ramesh Rijal1, Manoj Sah1, Hari Prasad Lamichhane2
1Physics Department, St. Xavier's College, Kathmandu, Nepal.
Abstract:
In this study, the molecular structures of nicotine and caffeine molecule have been generated using the 6-311++G(d,p) basis set in the DFT/B3LYP method. The molecules were optimized on the same basis set and their minimum stable energy was calculated. The HOMO-LUMO energies were calculated to establish the kinetic stability and chemical reactivity of the chosen compounds. The variation of energy and its gap were closely studied for both nicotine and caffeine in the presence of solvent water as well. Similarly, vibrational spectroscopy was studied at the most prominent region in both gas phase and solvent water with their respective TED assignments. The shifting of frequency clearly indicates the impact of solvent water and isotopic substitution of carbon atoms.
More Related Videos
Related Concept Videos
Chemical Shift: Internal References and Solvent Effects
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds
π Electron Effects on Chemical Shift: Overview
Real Gases: Effects of Intermolecular Forces and Molecular Volume Deriving Van der Waals Equation


