title: A new method to determine dispersive surface energy site distributions by inverse gas chromatography.
abstract: A computational model to predict the relative energy site contributions of a heterogeneous material from data collected by finite dilution-inverse gas chromatography (FD-IGC) is presented in this work. The methodology employed a multisolvent system site filling model utilizing Boltzmann statistics, expanding on previous efforts to calculate "experienced energies" at varying coverage, yielding a retention volume distribution allowing calculation of a surface free energy distribution. Surface free energy distributions were experimentally measured for racemic ibuprofen and β-mannitol powders, the energies of each were found in the ranges 43-52 and 40-55 mJ/m(2), respectively, over a surface coverage range of 0-8%. The computed contributions to surface energy values were found to match closely with data collected on macroscopic crystals by alternative techniques (±<1.5 mJ/m(2)).
authors.affiliation: Surfaces and Particle Engineering Laboratory, Department of Chemical Engineering, Imperial College London , South Kensington Campus, London SW7 2AZ, U.K.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Smith
authors.forename: Daryl R
authors.initials: DR
authors.lastname: Williams
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Burnett
authors.forename: Jerry Y Y
authors.initials: JY
authors.lastname: Heng