Formation of a bimolecular first layer intert-butanol on graphite

Abstract

We report here the pressure-volume isotherm and x-ray-diffraction measurements for tert-butanol on graphite over the temperature range 220–250 K, with comparison to the other branched isomers of butanol. Unlike the other butanols, the first adsorbed layer of tert-butanol forms a bimolecular-layer-thick film and undergoes two first-order phase transitions with increasing vapor pressure. Analysis of the x-ray-diffraction pattern shows that the bimolecular adsorbed layer shares the same helical structure of hydrogen bonds as found in the bulk.