Adam Wallace’s Research

web_picture4 Wallace C.V.

The nucleation and growth of carbonate minerals upon organic templates surfaces is widespread in natural and engineered environments. In the subsurface, carbonate mineralization may be promoted by biopolymer arrays on bacterial cell membranes. The stability of these phases determines the time scale over which they can act as natural sinks for carbon and heavy metals in the environment. My research uses rare-events simulation protocols and complimentary experiments to investigate the mechanisms of carbonate nucleation/growth and the influence of organic templates and living interfaces on these processes.

A snapshot from an atomistic simulation of the early stages of iron carbonate crystallization. Iron(II) and carbonate ions are shown in yellow and orange respectively. Extracellular biomolecules (glucuronic acid shown) and polymers associated with bacterial communities may promote carbonate mineral nucleation and assist in the formation of oriented crystals in subsurface environments under consideration for carbon sequestration. These simulations probe 1) the interplay between ion-dehydration processes and attachment / detachment kinetics which establish preferred ion-pairing motifs (polymorph selection) and 2) the influence of molecular substrates on the crystallization of disordered metal-carbonate ion-clusters (templated-mineralization).