【摘要】 以柔性大分子18－冠醚－6为研究对象，将MNDO法所得的三种构象的静电势电荷用于分子力学计算，得到了三种构象的能量，同时计算了电负性电荷，亦将其用于分子力学计算，将两种计算结果进行比较发现，有可能将电负性作为分子力学、分子动力学计算的力场参数．更多还原

【Abstract】 The scaled a6 initio 6-31G* ESP charges for three kinds of conformations (Ci, D3d, C1) of 18-crown-6 were calculated by MNDO. The conformation energies and structures were calculated by molecular mechanics. The results showed that the changes of charge-distribution in different conformations influenced the conformation energies significantly. Using the electronegative charges, the energies and structures were also obtained from molecular mechanics. The results were in good agreement with those using the MNDO scaling 6-31G* ESP charges. It suggested that the electronegativities could be used as the force field paratmeters in calculating various conformation energies in molecular mechanics and molecular dynamics.更多还原