Molecular Dynamics Simulations of Lignin Dimers onto FeOOH Mineral Surfaces
EMSL Project ID
50136
Abstract
Molecular-level information is needed to improve our understanding of the mechanisms that control terrestrial carbon stabilization in the form of soil organic matter (OM). This Rapid Access General Proposal requests 50,000 node-hours on the EMSL Cascade computer for a proof of principle computational study to investigate how differences in the chemical structure of lignin dimers affects its adsorption affinity to goethite (FeOOH) mineral surfaces through the use of molecular dynamics (MD) simulations. In the past decade, ultrahigh resolution mass spectrometry studies of soil OM have consistently shown that lignin-type molecules make up the dominant fraction of terrestrial OM. In addition, there is growing acceptance that the stability of soil OM is controlled by its adsorption to soil minerals, rather than due to some inherent chemical recalcitrance of the OM itself. This new understanding that it is the adsorption of OM to mineral surfaces that is providing protection from microbial biodegradation actions makes it more critical to get a better, molecular-level mechanistic understanding of adsorption process. This Rapid Access General Proposal seeks to demonstrate that MD simulation methods can further advance our understanding of how OM is sequestered soils by probing the molecular-level details of the adsorption process. It is anticipated that the ability to elucidate the molecular-level processes involved in the adsorption of lignin to FeOOH using molecular dynamics simulation will lead to development of development of a full, Science Theme Proposal in 2018 to broaden the scope of the investigation to address systematically address how structural differences in a wider range of lignin, aliphatic, and aromatic OM molecules affects its affinity for metal (oxy)hydroxide minerals such as FeOOH, as well as aluminosilicate minerals such as smectite. This new knowledge could potentially lead to management systems that enhancement of soil carbon sequestration to help lessen the impacts of anthropogenic CO2 release on climate change.
Project Details
Project type
Limited Scope
Start Date
2018-02-26
End Date
2018-04-28
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members