Atomic connectivity group contribution (ACGC) method for the phase
transition properties part 1: critical properties
In this work, atomic connectivity group contribution (ACGC) method is
developed for predicting critical properties of organic compounds.
Herein, a new group defining method, namely atomic adjacent group (AAG)
method, is proposed to describe the relationship between core atom and
its adjacent atoms. For distinguishing isomers effectively, the shape
factor (SF) is used to describe the effect of molecular shape on group,
and atomic connectivity factors (ACF) are defined for describing the
position of each group in a molecule. The external and internal
verification methods were utilized during the modelling process.
Compared with AAG model, ARE decreased by 6.82-42.57 % when SF was
considered and, ARE decreased by 24.19-62.25 % when both SF and ACF
were applied as using the ACGC method. Accordingly, SF and ACF are
effective in improving the group contribution method and ACGC method is
accurate in calculating the properties of organic compounds.