Modeling of type II high-resolution sorption isotherms: Evaluation of different approaches

General cluster sorption isotherm: surface area determination

“…In case of the sorption of water, n -pentane and neo-pentane the BET-based values are very near to those of the 2-dimensional GCSI because the full range isotherm of GCSI is similar to the full range BET. 13 However, the data representing nitrogen and argon sorption yield BET values being about 1.5 to 2 times greater than those obtained from GCSI.…”

“…Hence, the application of the GCSI inflection-point method can result in surface areas which are nearly identical with those of the BET method. There is no reason to oppose further against the theoretical validity of BET in principle, as done by the advocates of the ESW approach 9,10,13,19 and others. 2,8…”

“…A high β -value is necessary for the failure reduction near q → 1 (for q see eqn (1) below). The program for the usual version can be found in the ESI† of my previous paper, 13 the new version is part of the appended ESI† here.…”

“…Its meaning is discussed in ref. 13. It is also checked to which extent the curves simulated according the 1-dimensional GCSI resemble those simulated by the 2-dimensional version.…”

“…12 The equation can match the experimental data much better than BET, however, in some cases also the “chi plot” fails to reproduce the full isotherm. 13…”