On the Importance of CP-corrected Gradient Optimization in the Study of Hydrogen Bonded Systems  

作　　者：王伟周 蒲雪梅 郑文旭 黄宁表 田安民 

机构地区：[1]Department of Chemistry,Sichuan University [2]Department of Biology and Chemistry,City University of Hong Kong

出　　处：《Chinese Journal of Chemistry》2003年第12期1586-1590,共5页中国化学（英文版）

基　　金：ProjectsupportedbytheSpecialResearchFoundationofDoctoralEducationofChineseUniversity (No .2 0 0 2 0 610 0 2 4)andtheStrategicGrant (No .70 0 13 5 1)ofCityUniversityofHongKong

摘　　要：Geometries, harmonic vibrational frequencies and interaction energies of thewater-hydrogen sulfide dimer, hydrogen fluoride dimer and glycine zwitterion-water dimer weredetermined by the counterpoise-corrected (CP-corrected) gradient optimization that explicitlycorrects for the basis set superposition error (BSSE) and CP-uncorrected (normal) gradientoptimization respectively at the B3LYP and MP2 levels of theory, employing the popular Pople'sstandard 6-31G(d), 6-31G(d,p) and 6-311 + + G(d, p) basis sets in order to assess the importance ofCP-corrected gradient optimization in the study of hydrogen bonded systems. The normal optimizationof these three H-bonded systems obtained using these popular basis sets all yielded erratic results,whereas use of CP-corrected gradient optimization led to consistent results with those from largerbasis sets. So this CP receipt becomes useful and necessary to correctly describe large systems,where the use of small basis sets may be necessary.Geometries, harmonic vibrational frequencies and interaction energies of thewater-hydrogen sulfide dimer, hydrogen fluoride dimer and glycine zwitterion-water dimer weredetermined by the counterpoise-corrected (CP-corrected) gradient optimization that explicitlycorrects for the basis set superposition error (BSSE) and CP-uncorrected (normal) gradientoptimization respectively at the B3LYP and MP2 levels of theory, employing the popular Pople'sstandard 6-31G(d), 6-31G(d,p) and 6-311 + + G(d, p) basis sets in order to assess the importance ofCP-corrected gradient optimization in the study of hydrogen bonded systems. The normal optimizationof these three H-bonded systems obtained using these popular basis sets all yielded erratic results,whereas use of CP-corrected gradient optimization led to consistent results with those from largerbasis sets. So this CP receipt becomes useful and necessary to correctly describe large systems,where the use of small basis sets may be necessary.

关 键 词：ab initio calculation density functional theory BSSE CP-corrected gradientoptimization 

分 类 号：O631[理学—高分子化学]