the catalytically active components are also applied to the support material in highly disperse form in close proximity to the storage components the process assumes a modern internal combustion engine the operation of which is regulated by so called engine electronics engine electronics of this type have electronic data memories in which data tables also called engine mappings are filed or stored relating to the operating states of the internal combustion engine the term u201c filed u201d is used here for the data electronically stored in the engine electronics to create a clear distinction from the chemical and physical storage processes occurring in the exhaust gas system the data needed to carry out the process on the storage behaviour of the fresh storage catalyst as a function of the temperature and on the exhaust gas composition depending on the corresponding operating state of the engine are determined in advance and also filed in the engine electronics in the form of data tables for the catalyst so called catalyst mapping for this purpose the adsorbtion capacity of the fresh nitrogen oxides storage catalyst over all temperature ranges occurring in the operation of the engine is precisely determined the amount of nitrogen oxides stored on the catalyst depending on torque engine speed exhaust gas mass flow exhaust gas temperature and nitrogen oxides concentration in the exhaust gas.