MOLECULAR DESIGN SYNTHESIS USING STOCHASTIC OPTIMIZATION AS A TOOL FOR SCOPING AND SCREENING

This paper presents optimisation technology for the computer-aided des ign of molecules. A new approach is presented that combines stochastic optimisation and group-contribution methods to select chemicals with optimised properties. Each molecule is represented as a set of functio nal groups. The search follows an iterative procedure, where new molec ules are generated, evaluated and subjected to acceptance. The evaluat ion stage calls upon calculation of molecular properties using-availab le group-contribution expressions and databases. The proposed methodol ogy is illustrated with literature examples involving the design of re frigerants and liquid-liquid extraction solvents. The efficiency of th e search and the thermodynamic models employed are validated through p rocess simulation studies. The work reports novel molecular structures and significant improvements over conventional techniques. (C) 1998 E lsevier Science Ltd. All rights reserved.