Each data item within a data block is identified using a unique data name. The currently accepted AIF data names are listed and defined in Table . These data items form a first version of a core dictionary, which are primarily intended for reporting primary physisorption data. As a result, the dictionary contains information about crucial experimental parameters, basic sample characterization and adsorption and desorption measures, each distinguished by a data name prefix ( exptl , sample , adsorp and desorp ).