新乡学院学报（自然科学版）
新鄉學院學報（自然科學版）
신향학원학보（자연과학판）
JOURNAL OF XINXIANG UNIVERSITY(NATURAL SCIENCE EDITION)
2008年
3期
29-33
,共5页
密度泛函理论%键离解能%取代基效应%S-亚硝基硫醇
密度汎函理論%鍵離解能%取代基效應%S-亞硝基硫醇
밀도범함이론%건리해능%취대기효응%S-아초기류순
density functional theory%bond dissociation enthalpy%substituent effect%S-nitroso thiols
利用密度泛函理论(B3LYP,B3PW91,B3P86),使用6-31G**基组计算了乙氰溶液中S-亚硝基硫醇化合物中S-NO的键离解能.结果表明B3PW91/6-31G**方法计算得出的键离解能平均绝对偏差为7.36 kJ/mol,与实验符合比较好.因此,我们建议使用B3PW91/6-31G**方法来计算S-亚硝基硫醇化合物中S-NO的键离解能.进一步分析表明不同的取代基对S-NO的键离解能影响不同.当C6H5SNO中的一个H基团分别被2-CH3、4-CH3、4-Cl、4-NO2基组取代时,S-NO的键离解能降低2.09～12.54 kJ/mol.当C6H5SNO中的一个H基团分别被2-Cl、3-CH3、3-Cl、4-OH3基组取代时,S-NO的键离解能增加0.042～36.37 kJ/mol.
利用密度汎函理論(B3LYP,B3PW91,B3P86),使用6-31G**基組計算瞭乙氰溶液中S-亞硝基硫醇化閤物中S-NO的鍵離解能.結果錶明B3PW91/6-31G**方法計算得齣的鍵離解能平均絕對偏差為7.36 kJ/mol,與實驗符閤比較好.因此,我們建議使用B3PW91/6-31G**方法來計算S-亞硝基硫醇化閤物中S-NO的鍵離解能.進一步分析錶明不同的取代基對S-NO的鍵離解能影響不同.噹C6H5SNO中的一箇H基糰分彆被2-CH3、4-CH3、4-Cl、4-NO2基組取代時,S-NO的鍵離解能降低2.09～12.54 kJ/mol.噹C6H5SNO中的一箇H基糰分彆被2-Cl、3-CH3、3-Cl、4-OH3基組取代時,S-NO的鍵離解能增加0.042～36.37 kJ/mol.
이용밀도범함이론(B3LYP,B3PW91,B3P86),사용6-31G**기조계산료을청용액중S-아초기류순화합물중S-NO적건리해능.결과표명B3PW91/6-31G**방법계산득출적건리해능평균절대편차위7.36 kJ/mol,여실험부합비교호.인차,아문건의사용B3PW91/6-31G**방법래계산S-아초기류순화합물중S-NO적건리해능.진일보분석표명불동적취대기대S-NO적건리해능영향불동.당C6H5SNO중적일개H기단분별피2-CH3、4-CH3、4-Cl、4-NO2기조취대시,S-NO적건리해능강저2.09～12.54 kJ/mol.당C6H5SNO중적일개H기단분별피2-Cl、3-CH3、3-Cl、4-OH3기조취대시,S-NO적건리해능증가0.042～36.37 kJ/mol.
Quantum chemical calculations are used to estimate the bond dissociation energies (BDEs)for 11 S-nitrosothiols compounds.These compounds are studied by employing the hybrid density functional theory(B3LYP,B3PW91,B3P86)methods together with 6-31G**basis set.It is demonstrated that the B3PW91/6-31G**method can give good results of BDE.which has the mean absolute error of 7.36 kJ/mol.Considering the smaller mean absolute error at 631G**,we recommend the B3PW91 method combined with 6-31G**basis set,as a satisfactory method of computing the BDEs for removal of the NO group in RSNO compounds.Further analysis indicated that different substituent positions have different effect on BDE of the S-NO bond.The bond dissociation energy of the S-NO bond lowers 2.09～12.54 kJ/mol when a H group of C6H5SNO is substituted with 2-CH3,4-CH3,4-Cl,4-NO2 groups,respectively.While the bond dissociation energy of the S-NO bond increases 0.042～36.37 kJ/mol when a H group of C6 H5 SN0 is substituted with 2-Cl,3-CH3,3-Cl,4-OCH3 groups,respectively.
