DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Variations in proton transfer pathways and energetics on pristine and defect-rich quartz surfaces in water: Insights into the bimodal acidities of quartz

Journal Article · · Journal of Colloid and Interface Science

Hypothesis: Understanding the mechanisms of proton transfer on quartz surfaces in water is critical for a range of processes in geochemical, environmental, and materials sciences. The wide range of surface acidities ( >9 p K a units) found on the ubiquitous mineral quartz is caused by the structural variations of surface silanol groups. Molecular scale simulations provide essential tools for elucidating the origin of site-specific surface acidities. Simulations: We used density -functional tight -binding -based molecular dynamics combined with rare -event metadynamics simulations to probe the mechanisms of deprotonation reactions from ten representative surface silanol groups found on both pristine and defect -rich quartz (1 01) surfaces with Si vacancies. Findings: The results show that deprotonation is a highly dynamic process where both the surface hydroxyls and bridging oxygen atoms serve as the proton acceptors, in addition to water. Deprotonation of embedded silanols through intrasurface proton transfer exhibited lower p K a values with less H -bond participation and higher energy barriers, suggesting a new mechanism to explain the bimodal acidity observed on quartz surface. Defect sites, recently shown to comprise a significant portion of the quartz (101) surface, diversify the coordination and local H -bonding environments of the surface silanols, changing both the deprotonation pathways and energetics, leading to a wider range of p K a values (2.4 to 11.5) than that observed on pristine quartz surface (10.4 and 12.1).

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Argonne National Laboratory (ANL), Argonne, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB)
Grant/Contract Number:
AC05-00OR22725; AC02-05CH11231; AC02-06CH11357
OSTI ID:
2345310
Alternate ID(s):
OSTI ID: 2500780
Journal Information:
Journal of Colloid and Interface Science, Vol. 666; ISSN 0021-9797
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

References (56)

p K a at Quartz/Electrolyte Interfaces journal August 2016
Structures of quartz (100)- and (101)-water interfaces determined by x-ray reflectivity and atomic force microscopy of natural growth surfaces journal September 2002
Density-functional tight-binding for beginners journal November 2009
The Mineral-Water Interface: Where Minerals React with the Environment journal June 2013
Density functional tight binding-based free energy simulations in the DFTB+ program: Density Functional Tight Binding-Based Free Energy Simulations in the DFTB+ Program journal September 2018
A Recipe for the Computation of the Free Energy Barrier and the Lowest Free Energy Path of Concerted Reactions journal April 2005
Rigorous p K a Estimation of Amine Species Using Density-Functional Tight-Binding-Based Metadynamics Simulations journal December 2017
Periodic Density Functional Theory Study of Water Adsorption on the α-Quartz (101) Surface journal March 2011
Molecular Dynamics Study of Proton Binding to Silica Surfaces journal February 1998
Computation of the pK of liquid water using coordination constraints journal August 2000
Elucidating the Bimodal Acid−Base Behavior of the Water−Silica Interface from First Principles journal December 2009
Rb + Adsorption at the Quartz(101)–Aqueous Interface: Comparison of Resonant Anomalous X-ray Reflectivity with ab Initio Calculations journal February 2015
Kinetics from Metadynamics: Principles, Applications, and Outlook journal August 2023
Data Reweighting in Metadynamics Simulations journal March 2020
Acidity constants of lumiflavin from first principles molecular dynamics simulations journal January 2014
Stability and properties of new-generation metal and metal-oxide clusters down to subnanometer scale
  • de Lara-Castells, María Pilar; Puzzarini, Cristina; Bonačić-Koutecký, Vlasta
  • Physical Chemistry Chemical Physics, Vol. 25, Issue 22 https://doi.org/10.1039/D3CP90063K
journal January 2023
A Self-Consistent Charge Density-Functional Based Tight-Binding Scheme for Large Biomolecules journal January 2000
Parametrization and Benchmark of DFTB3 for Organic Molecules journal November 2012
Estimating p K a Values for Pentaoxyphosphoranes journal June 2002
Mineral-Aqueous Solution Interfaces and Their Impact on the Environment journal October 2012
Thermal decomposition of acetate: III. Catalysis by mineral surfaces journal October 1994
pH dependent reactivity of boehmite surfaces from first principles molecular dynamics journal January 2022
Investigations of water/oxide interfaces by molecular dynamics simulations journal June 2021
Vibrational spectra of water molecules at quartz/water interfaces journal January 1994
Density Functional Tight-Binding Simulations Reveal the Presence of Surface Defects on the Quartz (101)–Water Interface journal July 2021
PLUMED: A portable plugin for free-energy calculations with molecular dynamics journal October 2009
Surface acidity of quartz: understanding the crystallographic control journal January 2014
Acid–Base Properties of Cis-Vacant Montmorillonite Edge Surfaces: A Combined First-Principles Molecular Dynamics and Surface Complexation Modeling Approach journal January 2023
In situ time-resolved X-ray diffraction of tobermorite formation in autoclaved aerated concrete: Influence of silica source reactivity and Al addition journal May 2011
Computational Insights into Mg2+ Dehydration in the Presence of Carbonate journal February 2022
Acidity Constant (p K a ) Calculation of Large Solvated Dye Molecules: Evaluation of Two Advanced Molecular Dynamics Methods journal September 2016
Density functional tight binding: values of semi-empirical methods in an ab initio era journal January 2014
Acidity constants from vertical energy gaps: density functional theory based molecular dynamics implementation journal January 2008
Experimental Correlation Between Interfacial Water Structure and Mineral Reactivity journal May 2013
The elusive silica/water interface: isolated silanols under water as revealed by vibrational sum frequency spectroscopy journal January 2017
Direct Absolute p K a Predictions and Proton Transfer Mechanisms of Small Molecules in Aqueous Solution by QM/MM-MD journal May 2013
Proton and Ligand Adsorption at Silica- and Alumina-Water Interfaces Studied by Optical Second Harmonic Generation (SHG) journal January 1998
Polarization of water molecules at a charged interface: second harmonic studies of the silica/water interface journal April 1992
The Silica–Water Interface: How the Silanols Determine the Surface Acidity and Modulate the Water Properties journal February 2012
Assessing the Accuracy of Metadynamics journal April 2005
Phase-referenced nonlinear spectroscopy of the α-quartz/water interface journal December 2016
Vibrational Dynamics at Aqueous–Mineral Interfaces journal January 2022
Efficient Reconstruction of Complex Free Energy Landscapes by Multiple Walkers Metadynamics journal March 2006
Molecular Simulation of Water and Hydration Effects in Different Environments: Challenges and Developments for DFTB Based Models journal September 2014
Zero-point-of-charge prediction from crystal chemistry and solvation theory journal July 1994
DFTB+, a software package for efficient approximate density functional theory based atomistic simulations journal March 2020
A Time-Independent Free Energy Estimator for Metadynamics journal July 2014
DFTB3: Extension of the Self-Consistent-Charge Density-Functional Tight-Binding Method (SCC-DFTB) journal March 2011
Experimental aspects of use of the quartz crystal microbalance in solution journal October 1985
First-principles modelling of the new generation of subnanometric metal clusters: Recent case studies journal April 2022
Importance of Nuclear Quantum Effects on Aqueous Electrolyte Transport under Confinement in Ti3C2 MXenes journal October 2022
Concerted Metal Cation Desorption and Proton Transfer on Deprotonated Silica Surfaces journal August 2018
The dissolution kinetics of quartz in aqueous mixed cation solutions journal November 1999
Coordination effects on the binding of late 3d single metal species to cyanographene journal January 2023
Elucidating the Nature of theStreptomyces plicatusβ-Hexosaminidase-Bound Intermediate Using ab initio Molecular Dynamics Simulations journal December 2008
Determination of pKa Values via ab initio Molecular Dynamics and its Application to Transition Metal-Based Water Oxidation Catalysts journal June 2019