Introduction

Computational chemistry and molecular modeling are considered as prediction tools that give explanation to phenomena and chemical reactions, using approaches that are based on the laws of quantum mechanics and classical mechanics. In this particular case, we could infer whether a reaction may be given spontaneously by conducting experimentation. This minimizes the use of reagents and the generation of hazardous waste.

The methodology used is based on the electron density of atoms, that’s why only a representative part of the carbon nanotube (CNT) is used, this part contains a carboxyl group which interact directly with the carbodiimide EDC forming an unstable compound with a group which will react with the poliethylamide later, therefore, that’s why only one monomer is used.

Methodology

The theoretical study was carried out using the theory of density functional (DFT) implemented in the Gaussian 09 package, review A.02 and using the graphical display Gauss View 5.0. to make the calculations we use the B3LYP functional and the 6-31G basis set (d). Structures optimizations were conducted using water as the solvent with IEFPCM model. The energy of formation of the amidation reaction was obtained. The optimized structures with their respective energy are in Table 1

Results

The equation to determinate the energy of reaction is:

With thermal correction:

With thermal correction:

With thermal correction:

The results indicate that the reaction is going to be spontaneous.

Recomendations

It is feasible to establish an equation where the constant value of the reactants and products are set and they are not altered when ethyl-amide units increase or if is necessary to change the molecule that will bind to the CNT.

The equations is:

Conditions:

To give the reaction spontaneously, it requires that the constant value always presents a negative amount bigger than the sum of the variable values.