Generalized correlative index (GCI) is a novel user-oriented descriptor for molecular structural representation.By defining generalized correlative function (GCF), property correlative parameters (PCPs) and distance-r...Generalized correlative index (GCI) is a novel user-oriented descriptor for molecular structural representation.By defining generalized correlative function (GCF), property correlative parameters (PCPs) and distance-relational function (DRF), GCI is based on molecular topological pattern and mode of apex connection and is able to perform self-adaptation and regulation in actual problems, thus possessing more extensive applications and superior correlation with properties.Applying this index to normal boiling point (NBP) of three classes of organic compounds, the resultant QSPR models all have their correlative coefficients R_ cum above 0.99.It shows that GCI is superior in selecting molecular structures and correlating with molecular properties.展开更多
A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distr...A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distribution function.It could distinguish most of isomers that include cis-or trans-structure from organic compounds.Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen,nitrogen,chlorine,bromine and sulfur,are given.Compared with the predictions,results made use of the most common existing group contribution methods,the overall average absolute difference of boiling point predictions of 417 organic compounds is 4.2 K;and the average absolute percent derivation is 1.0%,which is compared with 12.3 K and 3.2% with the method of Joback,12.1 K and 3.1% with the method of Constantinou-Gani.This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability.展开更多
文摘Generalized correlative index (GCI) is a novel user-oriented descriptor for molecular structural representation.By defining generalized correlative function (GCF), property correlative parameters (PCPs) and distance-relational function (DRF), GCI is based on molecular topological pattern and mode of apex connection and is able to perform self-adaptation and regulation in actual problems, thus possessing more extensive applications and superior correlation with properties.Applying this index to normal boiling point (NBP) of three classes of organic compounds, the resultant QSPR models all have their correlative coefficients R_ cum above 0.99.It shows that GCI is superior in selecting molecular structures and correlating with molecular properties.
文摘A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distribution function.It could distinguish most of isomers that include cis-or trans-structure from organic compounds.Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen,nitrogen,chlorine,bromine and sulfur,are given.Compared with the predictions,results made use of the most common existing group contribution methods,the overall average absolute difference of boiling point predictions of 417 organic compounds is 4.2 K;and the average absolute percent derivation is 1.0%,which is compared with 12.3 K and 3.2% with the method of Joback,12.1 K and 3.1% with the method of Constantinou-Gani.This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability.
