Investigation of Solvent Effects on Armchair Single-Walled Carbon Nanotubes: A QM/MD Study

Abstract

In this research, we studied solvent effects on the relative energies, dipole moment values, and structural properties of water, methanol, ethanol, and mixtures of them surrounding single-walled carbon nanotubes (SWCNT), by using molecular dynamics simulation. Calculations were carried out with the Hyper Chem program. We used different force fields to determine energy and other types of geometrical parameters on the particular SWCNT. Because of the differences among force fields, the energy of a molecule calculated using two different force fields will not be the same. In this study, differences in force fields was illustrated by comparing the energy calculated by using force fields MM+, Amber and OPLS. The quantum Mechanics (QM) calculations were carried out with the GAUSSIAN 98 program based on density functional theory (DFT) at the B1LYP/3-21G level. In this study, we have compared gas phase and solvent calculations that considered solvents such as water, methanol and ethanol and a mixture of them. Therefore, we investigate polar solvents effects on SWCNT within the Onsager self-consistent reaction field (SCRF) model using a Hartree-Fock method and the temperature effect on the stability of SWCNT in various solvents.

Keywords:

• Solvent effect
• Quantum mechanics
• molecular dynamics
• DFT
• force field