Abstract: A new expert system has been developed which can be used to aid' chemists in structural interpretation of infrared spectra. The system consists of five essential components: knowledge-base, inference engine, database, knowledge-acquisition module and explanatory interface. The system is implemented in Turbo PROLOG artificial intelligence language. This system has the following advantages compared with other spectral interpretation, systems: the system has a greatly friendly user interface, two kinds of methods for managing knowledge-base, several useful explanatory facilities, such as WHY explanation, HOWexplanation etc. ; it can run on the IBM PC/XT and its compatible microcomputers. The system's another important feature is that it can simulate the reasoning an experienced chemist employs in interpreting spectra as well as deducing complete molecular strucures. So the system can also be used as a helpful learning tool for training chemistry students in IRspectrum interpretation and organic structure elucidation.

Key words: Expert system, IR, Molecule structure