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Three ordered mesoporous siliceous (OMS) materials known as MCM41s—unmodified MCM-41C16 (“C16”), and two MCM41s with different surface functionalities: MCM-41C16-SH (“C16-SH”) and MCM-41C16-NH2 (“C16-NH2”)—were synthesized and studied by inverse gas chromatography in order to determine their acceptor–donor properties. The specific retention volumes of nonpolar and polar probes that were chromatographed on these ordered mesoporous silica adsorbents were evaluated under infinite dilution conditions. Two methods were employed to calculate the standard free energy of adsorption, ΔGads, of each chromatographed probe on the basis its specific retention volume. These ΔGads values were then employed to estimate the van der Waals contribution and the specific contribution of the free surface energy for each MCM41. DN values (donor numbers, based on the Gutmann scale) and AN* values (acceptor numbers, based on the Riddle–Fowkes scale) were employed to determine the values of parameters that characterize the ability of the MCM41s to act as electron acceptors (parameter: KA) and donors (parameter: KD). Considering the different compositions of the probes, each of which has different acceptor–donor properties, a new chromatographic test to supplement the Grob test is suggested.

The values of the specific retention volumes of non-polar and polar adsorbates chromatographed on the ordered mesoporous silica adsorbents (MCMs) were determined under their infinite dilution conditions. Two methods were employed for the calculation of the standard free energy of adsorption, ∆G ads , of the chromatographed adsorbates on the basis of the specific retention volumes. The ∆G ads values were employed for the estimation of the van der Waals contribution and specific contribution of the free surface energy for the MCMs and the parameters characterising their ability to act as acceptors, K A , and donors, K D , of electrons.