Towards 'chemical congruence' of the models in theoretical chemistry

A series of 'growth crises' in the methodological framework of chemistry has led to serious discrepancies between the operational approach used in experimental practice and the methods and models used in theory. The theory, based on the quantum version of microphysics, has met difficulties in giving to its concepts an operational status congruent with that of experimental chemistry. The process of redefinition is examined here, on the basis of an analysis of theoretical chemical models and on criteria to judge their congruence with this process of methodological harmonization.