The PI proposes to purchase a Omnisorp 100 CX sorptometer (an adsorption) porosimeter) from Coulter. The instrument measures the surfaces area, pore volume, and micropore (20 A) and mesopore (20-500 A) size distribution of a porous solid sample based on the physical adsorption of N2. A volumetric method is used to measure the adsorption and desorption isotherms over a large pressure range, and from these the pore characteristics of the material can be calculated. The PI, together with collaborators, will use this instrument in several related studies, including: (i) Experiments to obtain date in well-characterized porous materials, and comparisons of this data with theoretical results using modern statistical mechanical Monte-Carlo and molecular dynamic simulations and (ii) characterizations of the porosity of intercalated composite silicate materials, and high surface area aluminas, silicas and alumino-silicates. The molecular dynamics simulations of the PI are of the highest quality, and the purchase of this instrument will facilitate the comparison of the simulations with experiments. The instrument will further the research of collaborators working on new layered and catalyst porous materials.