Computational Studies of Nanoparticle Formation Leading to Mineralization and ab initio Thermodynamics Studies of Minerals
EMSL Project ID
50472
Abstract
There is a critical need to develop an understanding of nanoparticle and mineral formation in systems that contain H2O, metal ions and CO2 as carbonation and hydrolysis reactions are important for the formation of minerals and their dissolution. Such processes are highly relevant to carbon dioxide capture and sequestration. We propose computational electronic structure studies of a variety of processes relevant to the formation of nanoparticles and minerals of the metal dications Mg2+, Ca2+, and Fe2+ in the presence of H2O and CO2. We propose to use advanced computational chemistry approaches implemented on EMSL's massively parallel computers to develop a quantitative description of these particle formation processes to develop new understanding of the physical phenomena that occur at different spatial and temporal scales that underlie such behavior. We will apply computational chemistry at the density functional theory (molecular and plane-wave) and correlated molecular orbital theory levels to study a range of processes including the following: (1) Predict the formation of nanoparticles from the ground up starting with monomers beginning with CaCO3; (2) Predict reliable heats of formation of monomers to predict cohesive energies of bulk minerals including the presence of waters of hydration; (3) Predict reliable heats of formation of small nanoparticles to provide data for a fragment-based energy decomposition scheme to obtain the energetic properties of larger nanoparticles and the bulk including phase transitions in the growth process and surface energy density map with a resolution of a few angstroms; and (4) Predict energetic properties of bulk minerals using ab initio density functional theory approaches. Accomplishing these tasks will enable us to understand how such nanoparticles form, for example, the important amorphous calcium carbonate, using bottom-up and top-down approaches. It will also provide insights into the role of waters of hydration on such processes at the microscopic level. The calculated spectroscopic properties provide a direct connection to experimental measurements being conducted by other EMSL users as well as providing a means to validate the predictions. A team of researchers from a US university, a Chinese academic institute, and PNNL with direct and close ties to experimental efforts will address these problems using appropriate computational methods. The proposed computational work is being done in close collaboration with experimental teams, a number of which use EMSL resources or are located in the EMSL. The effort falls within the EMSL Environmental Sciences Area: "Understand mineral surface complexation/associations, redox reactions, nanoparticle and colloid formation, and their impact on the reactivity, fate, and transport of anthropogenic contaminants and complexes in terrestrial, aquatic and subsurface ecosystems, and the BER High Level Grand Challenges in Biogeochemistry and Data-model integration."
Project Details
Project type
Exploratory Research
Start Date
2018-10-21
End Date
2019-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members