用解析函数拟合NH3复合分子中质子转移势能的理论研究  

Theory Study on the Analytic Functions Fit to Proton Transfer Potentials in Ammonia Complex

作　　者：王荣顺[1] 潘秀梅[1] 苏忠民[1] SCHEINER Steve 

机构地区：[1]东北师范大学化学学院,功能材料化学研究所, [2]bDepartment of Chemistry Biochemistry, Utah State University, Logan UT 84322 - 0300, U.S.A.

出　　处：《化学学报》2001年第12期2056-2062,共7页Acta Chimica Sinica

摘　　要：采用量子化学ab initio(4-31G基组)方法,计算了NH3复合分子(H3N…H+…NH3)中的质子转移势能,氢键长度和取向的变化都没有影响它的双势阱特征,长度越长、分子主轴偏离氢键键轴越大,双势阱间能垒越高.采用最小二乘法拟合上述ab initio计算结果,找到了理想的解析函数,从而扩大其适用范围.针对体系的对称性和非对称性,我们改进了φ4函数和Morse函数,从而使拟合结果得到了明显提高,拟合相关系数最高达0.999.Proton transfer potentials in ammonia complex (H3NH+)-H-... (...) NH3 are calculated by using the quantum chemical ab initio method (4 - 31G basis set). It shows that the variations of H - bond length and its orientation make no impact on the characteristics of double potential wells. The longer H - bond length and the more heavily the molecular main axle deviated from H - bond axle, the higher the energy barrier between double potential wells. Suitable analytic functions can be found with least square fitting to the ab initio results so as to extend the analytic functions' usage range. Considering the system's symmetry and unsymmetry, we modify phi (4) functions and Morse functions. So the simulation results are noticeably improved, and the highest fitting correlation coefficient can reach 0.999.

关 键 词：质子迁移 解析函数 NH3复合分子 ab INITIO 氢键 拟合 氨分子 量子化学 势能 势能曲线 

分 类 号：O613.61[理学—无机化学] O641.121[理学—化学]