This reasoning, from the perspective of the reduction of exposed surface area can also help understand the unexpected stability of the linear, column bound motif in the full pore norspermine, while the binding energy of a single norspermine in the pore predicts diagonal binding. Because it relates the stability of adsorption system to the amount of surface area loss, and more loss of exposed surface will destabilize the adsorption system, from Figure , diagonally bound amines can fully cover the surface area of the DOBPDC linker, but the linear, column bound amines leave most of the linker surface area open.