N Shadmani - Young Researchers and Elite Club, Rasht Branch, Islamic Azad University, Rasht, Iran
S Ghorbaninezhad - Department of Chemistry, Arak Branch, Islamic Azad University, Arak, Iran
M Shadmani - Young Researchers and Elite Club, Rasht Branch, Islamic Azad University, Rasht, Iran

The DFT calculations have been performed using the Gauss view and Gaussian03 in B3LYP method and 6-31G (d) standard basis set at 298.15K and 1 atm. There are calculated length bond (Å), bond angel (°),energy hyperconjugation, moment dipole (Debye), E gap ,between calix[6]arene and 5- Fluorouracil at B3LYP/6-31G (d) method.These cases are show that 5-Fu-calix[6]arene at site A more stable than site B. The parameter of, and E°, G°, H°, and S°total, in compounds of 5-Fu-calix[6]arene at site A are negative than 5-Fu-calix[6]arene at site B; therefore, A is morestable.

NBO , DFT , nanocalix[6]arene , nano cavity , 5- Fluorouracil