Title: Quantum Chemical Approach for Calculating Stability Constants of Mercury Complexes

Journal Article · · ACS Earth and Space Chemistry
 [1];  [2];  [3];  [2];  [4]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). UT/ORNL Center for Molecular Biophysics. Biosciences Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Biochemistry and Cellular and Molecular Biology; University of Tennessee Knoxville
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). UT/ORNL Center for Molecular Biophysics. Biosciences Division
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). UT/ORNL Center for Molecular Biophysics. Biosciences Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Biochemistry and Cellular and Molecular Biology
+ Show Author Affiliations

Stability constants are central to the multi-scale modeling of the thermodynamic speciation, cycling, and transport of mercury (Hg) and other contaminants in aquatic environments. However, for Hg, experimental values for many relevant complexes are not available, and for others can span ranges in excess of 10 log units. The missing data and large uncertainties mean there are significant knowledge gaps in predictions of thermodynamic speciation. As an alternative to experimental measurements, thermodynamic quantities can be calculated with quantum chemical methods. Among these, density functional theory (DFT) with a polarizable continuum solvent combines accuracy with practicability. In this paper, we present an accurate and quick approach in which we use DFT with continuum solvation to calculate stability constants of Hg complexes with inorganic and low molecular-weight organic ligands in aqueous solution. Specifically, we use the M06/[SDD]6-31+G(d,p) level of theory in combination with a modified version of the SMD solvent model in which the solute radii are re-optimized with a scaled solvent-accessible surface (sSAS) approach. For the set of 37 Hg complexes used for optimization, which contain environmentally relevant functional groups and have reliable experimental stability constants, we obtain a mean unsigned error of 1.4 log units. Testing the method on an independent set of 12 Hg complexes reproduces the experimental stability constants to a mean unsigned error of 1.6 log units. Finally, this approach is a substantial step toward generally applicable rapid stability constant derivation for a wide range of Hg complexes, including those present in dissolved organic matter.

Research Organization:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Grant/Contract Number:
AC05-00OR22725; SC0016478
OSTI ID:
1475452
Journal Information:
ACS Earth and Space Chemistry, Journal Name: ACS Earth and Space Chemistry Journal Issue: 11 Vol. 2; ISSN 2472-3452
Publisher:
American Chemical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

References (86)

Formation of a Dinuclear Mercury(II) Complex with a Regular Bis-Strapped Porphyrin Following a Tunable Cooperative Process journal January 2011
Toward robust computational electrochemical predicting the environmental fate of organic pollutants journal May 2011
Optimization of solute cavities and van der Waals parameters inab initio MST-SCRF calculations of neutral molecules journal April 1994
DFT and TD-DFT investigation of IR and UV spectra of solvated molecules: Comparison of two SCRF continuum models journal January 2007
The sulphur-mercury(II) system in natural waters journal April 1991
Systematically convergent basis sets for transition metals. II. Pseudopotential-based correlation consistent basis sets for the group 11 (Cu, Ag, Au) and 12 (Zn, Cd, Hg) elements journal August 2005
The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals journal July 2007
Sequestering ability of some chelating agents towards methylmercury(II) journal September 2012
Reactive Transport Modeling of Subaqueous Sediment Caps and Implications for the Long-Term Fate of Arsenic, Mercury, and Methylmercury journal April 2012
A reactive transport model for mercury fate in soil—application to different anthropogenic pollution sources journal June 2014
A reactive transport model for mercury fate in contaminated soil—sensitivity analysis journal June 2015
Ab initio study of solvated molecules: a new implementation of the polarizable continuum model journal June 1996
Mercury(II) complexes with sulfhydryl containing chelating agents: Stability constant inconsistencies and their resolution journal January 1980
The interpretation of protein structures: Estimation of static accessibility journal February 1971
Metal chelate exchange in the organic phase—II Extraction and exchange constants of dithizonates and diethyldithiocarbamates journal June 1968
Optimization of the cavity size for ab initio MST-SCRF calculations of monovalent ions journal May 1994
Determination of extraction constants of metal diethyldithiocarbamates journal January 1968
Determination of the composition and the stability constants of complexes of mercury(II) with amino acids journal January 1974
Interactions between mercury and dissolved organic matter––a review journal April 2004
Geochemical cycling of mercury in a deep, confined aquifer: Insights from biogeochemical reactive transport modeling journal April 2013
Determination of extraction constants for metal diethyldithiocarbamates and chloride-mixed metal diethyldithiocarbamates by substoichiometric extraction journal March 1980
Cysteine Inhibits Mercury Methylation by Geobacter sulfurreducens PCA Mutant Δ omcBESTZ journal April 2015
Identification of Mercury and Dissolved Organic Matter Complexes Using Ultrahigh Resolution Mass Spectrometry journal December 2016
Predicting Stability Constants for Uranyl Complexes Using Density Functional Theory journal March 2015
Calculation of Ligand Dissociation Energies in Large Transition-Metal Complexes journal March 2018
Density Functional Theory Calculation of p K a ’s of Thiols in Aqueous Solution Using Explicit Water Molecules and the Polarizable Continuum Model journal June 2016
Modeling Flexible Molecules in Solution: A p K a Case Study journal June 2017
Quantum Chemical Calculation of p K a s of Environmentally Relevant Functional Groups: Carboxylic Acids, Amines, and Thiols in Aqueous Solution journal April 2018
Calculating Free Energy Changes in Continuum Solvation Models journal February 2016
Combining Explicit Quantum Solvent with a Polarizable Continuum Model journal October 2017
Marine Biogeochemical Cycling of Mercury journal February 2007
Quantum Mechanical Continuum Solvation Models journal August 2005
An Implicit Solvent Model for SCC-DFTB with Charge-Dependent Radii journal July 2010
Cluster-Continuum Calculations of Hydration Free Energies of Anions and Group 12 Divalent Cations journal December 2012
Theoretical Determination of One-Electron Oxidation Potentials for Nucleic Acid Bases journal September 2012
Self-Consistent Reaction Field Model for Aqueous and Nonaqueous Solutions Based on Accurate Polarized Partial Charges journal October 2007
p K a Calculation of Some Biologically Important Carbon Acids - An Assessment of Contemporary Theoretical Procedures journal January 2009
Strong Hg(II) Complexation in Municipal Wastewater Effluent and Surface Waters journal June 2003
Importance of Dissolved Neutral Mercury Sulfides for Methyl Mercury Production in Contaminated Sediments journal April 2007
Mechanisms Regulating Mercury Bioavailability for Methylating Microorganisms in the Aquatic Environment: A Critical Review journal February 2013
Refining Thermodynamic Constants for Mercury(II)-Sulfides in Equilibrium with Metacinnabar at Sub-Micromolar Aqueous Sulfide Concentrations journal April 2013
Zero-Valent Sulfur and Metal Speciation in Sediment Porewaters of Freshwater Lakes journal October 2009
Kinetic Controls on the Complexation between Mercury and Dissolved Organic Matter in a Contaminated Environment journal November 2009
Sulfide Controls on Mercury Speciation and Bioavailability to Methylating Bacteria in Sediment Pore Waters journal March 1999
Density Functional Theory-Based Prediction of the Formation Constants of Complexes of Ammonia in Aqueous Solution:  Indications of the Role of Relativistic Effects in the Solution Chemistry of Gold(I) journal October 2005
Predicting the Stability Constants of Metal-Ion Complexes from First Principles journal September 2013
Mercury Methylation by HgcA: Theory Supports Carbanion Transfer to Hg(II) journal December 2013
Mechanism of Hg−C Protonolysis in the Organomercurial Lyase MerB journal September 2009
Potentiometric, Calorimetric, and 1 H NMR Investigation on Hg 2+ -Mercaptocarboxylate Interaction in Aqueous Solution journal May 2011
Sequestration of Hg 2+ by Some Biologically Important Thiols journal December 2011
Interaction of Inorganic Mercury(II) with Polyamines, Polycarboxylates, and Amino Acids journal January 2009
New Universal Solvation Model and Comparison of the Accuracy of the SM5.42R, SM5.43R, C-PCM, D-PCM, and IEF-PCM Continuum Solvation Models for Aqueous and Organic Solvation Free Energies and for Vapor Pressures journal July 2004
Adding Explicit Solvent Molecules to Continuum Solvent Calculations for the Calculation of Aqueous Acid Dissociation Constants journal February 2006
Aqueous Solvation Free Energies of Ions and Ion−Water Clusters Based on an Accurate Value for the Absolute Aqueous Solvation Free Energy of the Proton journal August 2006
Interaction of Metal Ions with Biomolecular Ligands: How Accurate Are Calculated Free Energies Associated with Metal Ion Complexation? journal October 2011
Theoretical Study of the Formation of Mercury (Hg 2+ ) Complexes in Solution Using an Explicit Solvation Shell in Implicit Solvent Calculations journal September 2014
Calculation of Solvation Free Energies of Charged Solutes Using Mixed Cluster/Continuum Models journal August 2008
Hydration of Copper(II): New Insights from Density Functional Theory and the COSMO Solvation Model journal September 2008
Calculation of p K a Values of Nucleobases and the Guanine Oxidation Products Guanidinohydantoin and Spiroiminodihydantoin using Density Functional Theory and a Polarizable Continuum Model journal December 2008
Universal Solvation Model Based on Solute Electron Density and on a Continuum Model of the Solvent Defined by the Bulk Dielectric Constant and Atomic Surface Tensions
  • Marenich, Aleksandr V.; Cramer, Christopher J.; Truhlar, Donald G.
  • The Journal of Physical Chemistry B, Vol. 113, Issue 18, p. 6378-6396 https://doi.org/10.1021/jp810292n
journal May 2009
Solvent Effects. 5. Influence of Cavity Shape, Truncation of Electrostatics, and Electron Correlation on ab Initio Reaction Field Calculations journal January 1996
Thermodynamic Parameters for the Solvation of Monatomic Ions in Water journal December 1999
Prediction of Vapor Pressures from Self-Solvation Free Energies Calculated by the SM5 Series of Universal Solvation Models journal May 2000
Resolution of a Challenge for Solvation Modeling: Calculation of Dicarboxylic Acid Dissociation Constants Using Mixed Discrete–Continuum Solvation Models journal May 2012
Why Mercury Prefers Soft Ligands journal June 2013
Competition among thiols and inorganic sulfides and polysulfides for Hg and MeHg in wetland soils and sediments under suboxic conditions: Illumination of controversies and implications for MeHg net production: COMPETITION AMONG S LIGANDS FOR Hg journal June 2008
High methylation rates of mercury bound to cysteine by Geobacter sulfurreducens journal January 2009
Prediction of formation constants of metal–ammonia complexes in aqueous solution using density functional theory calculations journal January 2004
Are thermodynamic cycles necessary for continuum solvent calculation of pK a s and reduction potentials? journal January 2015
Density functional theory for transition metals and transition metal chemistry journal January 2009
Theoretical calculations of stability constants and pKa values of metal complexes in solution: application to pyridoxamine–copper(ii) complexes and their biological implications in AGE inhibition journal January 2013
Predicting aqueous solubilities from aqueous free energies of solvation and experimental or calculated vapor pressures of pure substances journal July 2003
The H2O2+OH→HO2+H2O reaction in aqueous solution from a charge-dependent continuum model of solvation journal July 2008
An efficient implementation for determining volume polarization in self-consistent reaction field theory journal November 2008
Gaussian basis sets for use in correlated molecular calculations. I. The atoms boron through neon and hydrogen journal January 1989
Gaussian basis sets for use in correlated molecular calculations. III. The atoms aluminum through argon journal January 1993
Predicting pKa in Implicit Solvents: Current Status and Future Directions journal January 2014
Thermodynamic stability of mercury(II) complexes formed with environmentally relevant low-molecular-mass thiols studied by competing ligand exchange and density functional theory journal January 2017
Ab initio quantum chemistry: Methodology and applications journal May 2005
Active transport, substrate specificity, and methylation of Hg(II) in anaerobic bacteria journal May 2011
Solvent polarity scales revisited: a ZINDO-PCM study of the solvatochromism of betaine-30 journal March 2006
The Genetic Basis for Bacterial Mercury Methylation journal February 2013
Solvent-accessible surfaces of proteins and nucleic acids journal August 1983
Nuclear magnetic resonance studies of the solution chemistry of metal complexes. XVII. Formation constants for the complexation of methylmercury by sulfhydryl-containing amino acids and related molecules journal May 1981
Critical evaluation of the stability constants of metal complexes of amino acids with polar side chains (Technical Report) journal January 1995
Chemical speciation of environmentally significant heavy metals with inorganic ligands. Part 1: The Hg2+– Cl–, OH–, CO32–, SO42–, and PO43– aqueous systems (IUPAC Technical Report) journal January 2005

Cited By (1)

The AQUA‐MER databases and aqueous speciation server: A web resource for multiscale modeling of mercury speciation journal October 2019

Similar Records

Quantum Chemical Calculation of pKas of Environmentally Relevant Functional Groups: Carboxylic Acids, Amines, and Thiols in Aqueous Solution
Journal Article · 2018 · Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory · OSTI ID:1459306
+1 more
Multi-Scale Modeling Framework for Mercury Biogeochemistry
Technical Report · 2020 · OSTI ID:1671770
Universal Solvation Model Based on Solute Electron Density and on a Continuum Model of the Solvent Defined by the Bulk Dielectric Constant and Atomic Surface Tensions
Journal Article · 2009 · Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry · OSTI ID:979505

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
DFT
continuum models
functional groups of dissolved organic matter
mercury
stability constants