计算机与应用化学
計算機與應用化學
계산궤여응용화학
COMPUTERS AND APPLIED CHEMISTRY
2010年
12期
1711-1714
,共4页
无机含水量氧酸%pK1%极化统一模型%从头计算%电子密度%定量结构性质关系
無機含水量氧痠%pK1%極化統一模型%從頭計算%電子密度%定量結構性質關繫
무궤함수량양산%pK1%겁화통일모형%종두계산%전자밀도%정량결구성질관계
inorganic oxyaeid%pK1%PCM%ab initio%electronic density%QSPR
采用Tomasi的极化统一模型对20种无机含氧酸HnROm在水相条件下进行从头算，选取14个量化参数结合含氧酸非羟基氧原子数等2个重要结构参数对含氧酸pK1进行逐步回归,引入非羟基氧原子数No、非羟基氧原子将电荷数NCo、羟基氢原子将电荷数NCH(O)和氢氧间的重叠布居数POPR-O(H)4个参数建立QSPR方程,方程相关系数R为0.9946,且有F＞Fa,表明方程回归效果显著,对回归系数的双边t检验结果均有 P＜0.05,表明此4个参数对pK1影响显著.对引入参数的物理意义及其对含氧酸pK1的影响分析表明,此4个参数均与羟基氧原子电子密度相关;其中NCH(O)和NO是影响含氧酸强度的主要因素,且NCH(O)的影响更大;NCO和POPR-O(H)则是影响含氧酸强度的次要因素,可用于区分各含氧酸强度的细微差别.此外，将 NCH(O)、POPR-O(H)m用于对35种酸碱进行分类也获得了良好的效果,表明此2个参数可用于区分R-O-H的电离方式.
採用Tomasi的極化統一模型對20種無機含氧痠HnROm在水相條件下進行從頭算，選取14箇量化參數結閤含氧痠非羥基氧原子數等2箇重要結構參數對含氧痠pK1進行逐步迴歸,引入非羥基氧原子數No、非羥基氧原子將電荷數NCo、羥基氫原子將電荷數NCH(O)和氫氧間的重疊佈居數POPR-O(H)4箇參數建立QSPR方程,方程相關繫數R為0.9946,且有F＞Fa,錶明方程迴歸效果顯著,對迴歸繫數的雙邊t檢驗結果均有 P＜0.05,錶明此4箇參數對pK1影響顯著.對引入參數的物理意義及其對含氧痠pK1的影響分析錶明,此4箇參數均與羥基氧原子電子密度相關;其中NCH(O)和NO是影響含氧痠彊度的主要因素,且NCH(O)的影響更大;NCO和POPR-O(H)則是影響含氧痠彊度的次要因素,可用于區分各含氧痠彊度的細微差彆.此外，將 NCH(O)、POPR-O(H)m用于對35種痠堿進行分類也穫得瞭良好的效果,錶明此2箇參數可用于區分R-O-H的電離方式.
채용Tomasi적겁화통일모형대20충무궤함양산HnROm재수상조건하진행종두산，선취14개양화삼수결합함양산비간기양원자수등2개중요결구삼수대함양산pK1진행축보회귀,인입비간기양원자수No、비간기양원자장전하수NCo、간기경원자장전하수NCH(O)화경양간적중첩포거수POPR-O(H)4개삼수건립QSPR방정,방정상관계수R위0.9946,차유F＞Fa,표명방정회귀효과현저,대회귀계수적쌍변t검험결과균유 P＜0.05,표명차4개삼수대pK1영향현저.대인입삼수적물리의의급기대함양산pK1적영향분석표명,차4개삼수균여간기양원자전자밀도상관;기중NCH(O)화NO시영향함양산강도적주요인소,차NCH(O)적영향경대;NCO화POPR-O(H)칙시영향함양산강도적차요인소,가용우구분각함양산강도적세미차별.차외，장 NCH(O)、POPR-O(H)m용우대35충산감진행분류야획득료량호적효과,표명차2개삼수가용우구분R-O-H적전리방식.
A descriptive and interpretable model,based on a quantitatixe structure-property relationship (QSPR),is developed using stepwise regression approach and quantum chemical descriptors derived from ab initio methods for some inorganic oxyacids (HnROm). By molecular modeling and calculation of descriptors,the number of the oxygen atom in non-hydroxyl (No),net charge of the oxygen atom in non-hydroxyl (NCo),net charge of the hydrogen atom in hydroxyl (NCH(O)),and overlap population between center atom R and hydroxyl oxygen atom (POPR-O(H)),were picked out to constitute the equation of QSPR.The equation has the correlation coefficient R of 0.9947 and the standard derivation s of 0.5804. Furthermore,the two-sided t-test was used to validate the significance of the 4 descriptors. The statistically significant (P<0.05) correlation coefficients of descriptors show that the 4 descriptors have important impact on the pK1 values. The studies of the 4 descriptors with pK1 values of inorganic oxyacids indicate that the 4 descriptors are related to the electronic density of oxygen atom in hydroxyl; No and NCH(O) are the main factors which affect the acidity strength of inorganic oxyacids,NCo and POPR-O(H) have the less effect,but they can distinguish the nuance of acidity strength between the inorganic oxyacids. In addition,NCo and POPR-O(H) can efficiently classify the 35 acids and alkali,which indicate that they can distinguish the mode of ionization of R-O-H.
