| Autor: |
Heimann JE; Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States., Tucker JD; Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States., Huff LS; Department of History, Geography, and Museum Studies, Morgan State University, Baltimore, Maryland 21251, United States., Kim YR; Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States., Ali J; Mechanical Engineering Department, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States., Stroot MK; Department of Chemistry, McDaniel College, Westminster, Maryland 21157, United States., Welch XJ; Biology Department, Morgan State University, Baltimore, Maryland 21251, United States., White HE; Department of Chemistry, McDaniel College, Westminster, Maryland 21157, United States., Wilson ML; Department of Chemistry, Towson University, Towson, Maryland 21252, United States., Wood CE; Department of Chemistry and Biochemistry, St. Mary's College of Maryland, St. Mary's City, Maryland 20686, United States., Gates GA; Walters Art Museum, Baltimore, Maryland 21201, United States., Rosenzweig Z; Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States., Bennett JW; Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, United States. |
| Abstrakt: |
Humans have incorporated minerals in objects of cultural heritage importance for millennia. The surfaces of these objects, which often long outlast the humans that create them, are undeniably exposed to a diverse mixture of chemicals throughout their lifetimes. As of yet, the art conservation community lacks a nondestructive, accurate, and inexpensive flexible computational screening method to evaluate the potential impact of chemicals with art, as a complement to experimental studies. In this work, we propose periodic density functional theory (DFT) studies as a way to address this challenge, specifically for the aragonite phase of calcium carbonate, a mineral that has been used in pigments, marble statues, and limestone architecture since ancient times. Computational models allow art conservation scientists to better understand the atomistic impact of small-molecule adsorbates on common mineral surfaces across a wide variety of environmental conditions. To gain insight into the surface adsorption reactivity of aragonite, we use DFT to investigate the atomistic interactions present in small-molecule-surface interfaces. Our adsorbate set includes common solvents, atmospheric pollutants, and emerging contaminants. Chemicals that significantly disrupt the surface structure such as carboxylic acids and sulfur-containing molecules are highlighted. We also focus on comparing adsorption energies and changes in surface bonds, which allows for the identification of key features in the electronic structure presented in a projected-density-of-state analysis. The trends outlined here will guide future experiments and allow art conservators to gain a better understanding of how a wide range of molecules interact with an aragonite surface under variable conditions and in different environments. |
