A data-oriented CI program system

A program system has been developed for calculation of molecular electronic structure using the configuration interaction (CI) method. Emphasis is placed on the inherent genealogical data structure of the files which a program system produces. Based on this genealogy, a language is provided for users which allows easy and consistent manipulation of files in the new system. Users need only specify a file which contains the desired data, using this file manipulation language. If the desired file does not exist, the new system creates it automatically by calling appropriate modules. The new system may be regarded as a data base equipped with computational ability.