Exploring the Macroscopic Properties of Humic Substances Using Modeling and Molecular Simulations

Soil organic matter (SOM) is composed of a complex and heterogeneous mixture compounds, which poses challenge in understanding it on an atomistic level. Based the progress molecular dynamics simulations our efforts to create systems that resemble SOM, this work, we expanded knowledge SOM through use humic substances (HSs). Specifically, studied standardized samples HS International Humic Substances Society (IHSS). This society provided elemental composition used as input parameters for Vienna Organic Matter Modeler 2 (VSOMM2). We modeled simulated different from various sources, including soil, peat, leonardite, blackwater river. In order compare between HS, reduced information two principal components, are associated principally with amount carboxyl aromatic groups denominated PCacid PCarom, respectively. performed plethora analyses characterize structure systems, total potential energy, density, diffusion, preferential solvation, hydrogen bonds, salt bridges. general terms, at water content value 0.2, observed most properties depend group protonation state. The Coulombic interactions ionic specie interaction cations determine overall behavior systems. Furthermore, type pH influence those properties. study exemplifies importance explain macroscopic molecules modeled, such network, i.e., bonds or bridges presented system their mobility.