The structure of monomeric and dimeric uranyl adsorption complexes on gibbsite: A combined DFT and EXAFS study

Hattori, Tatsuya; Saito, Takumi; Ishida, Keisuke; Scheinost, Andreas C.; Tsuneda, Takao; Nagasaki, Shinya; Tanaka, Satoru

doi:10.1016/j.gca.2009.07.004

Cited by 76 publications

(90 citation statements)

References 61 publications

(94 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Under oxidizing environmental conditions, the hexavalent form is the most prominent. The sorption of U(VI) on a multiplicity of naturally occurring and artificial substrates has been intensively studied in the last decades, using macroscopic batch and column experiments, spectroscopic and microscopic analysis, theoretical calculations and modeling (Waite et al, 1994;Bargar et al, 2000;Duff et al, 2002;Catalano et al, 2005;Arai et al, 2006;Perron et al, 2006;Ulrich et al, 2006;Chardon et al, 2008;Pasilis and Pemberton, 2008;Sherman et al, 2008;Hattori et al, 2009;Rossberg et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

“…Under near neutral conditions, where several uranyl hydroxo species dominate the speciation, deprotonation of hydroxyl groups of oxide surfaces potentially provides an increased number of adsorption sites. These processes may be accompanied by stronger inner-shell surface adsorption and by the formation of aqueous polynuclear complexes which can be sorbed onto the surfaces or might induce surface precipitation (Prikryl et al, 1994;Sylwester et al, 2000;Hattori et al, 2009;Rossberg et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sorption of U(VI) at the TiO2–water interface: An in situ vibrational spectroscopic study

Müller

Foerstendorf

Meusel

et al. 2012

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Sorption of U(VI) at the TiO2–water interface: An in situ vibrational spectroscopic study

Müller

Foerstendorf

Meusel

et al. 2012

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

“…Our principal objective is to examine whether Pb-DES is the only stable surface complex that can occur on the lateral edges of these nanoparticles. First-principles techniques such as DFT can be applied to reduce ambiguities and guide the interpretation of EXAFS spectra by providing complementary electronic structure and bonding information about metals adsorbed on mineral surfaces (Zhang et al, 2006;Sherman et al, 2008;Hattori et al, 2009;Mason et al, 2009;Kwon et al, 2009). In particular, spinpolarized DFT (i.e., electron densities are calculated separately for spin-up and spin-down electrons) accurately predicts crystal structures and electronic properties of Mn oxides (Singh, 1997;Mishra and Ceder, 1999;Pask et al, 2001), including birnessite (Kwon et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

Surface complexation of Pb(II) by hexagonal birnessite nanoparticles

Kwon

Refson

Sposito

2010

Geochimica et Cosmochimica Acta

View full text Add to dashboard Cite

Natural hexagonal birnessite is a poorly-crystalline layer type Mn(IV) oxide precipitated by bacteria and fungi which has a particularly high adsorption affinity for Pb(II). X-ray spectroscopic studies have shown that Pb(II) forms strong inner-sphere surface complexes mainly at two sites on hexagonal birnessite nanoparticles: triple corner-sharing (TCS) complexes on Mn(IV) vacancies in the interlayers and double edge-sharing (DES) complexes on lateral edge surfaces. Although the TCS surface complex has been well characterized by spectroscopy, some important questions remain about the structure and stability of the complexes occurring on the edge surfaces. First-principles simulation techniques such as density functional theory (DFT) offer a useful way to address these questions by providing complementary information that is difficult to obtain by spectroscopy. Following this computational approach, we used spinpolarized DFT to perform total-energy-minimization geometry optimizations of several possible Pb(II) surface complexes on model birnessite nanoparticles similar to those that have been studied experimentally. We first validated our DFT calculations by geometry optimizations of (1) the Pb-Mn oxyhydroxide mineral, quenselite (PbMnO 2 OH), and (2) the TCS surface complex, finding good agreement with experimental structural data while uncovering new information about bonding and stability. Our geometry optimizations of several protonated variants of the DES surface complex led us to conclude that the observed edge-surface species is very likely to be this complex if the singly-coordinated terminal O that binds to Pb(II) is protonated. Our geometry optimizations also revealed that an unhydrated double corner-sharing (DCS) species that has been proposed as an alternative to the DES complex is intrinsically unstable on nanoparticle edge surfaces, but could become stabilized if the local coordination environment is 3 well-hydrated. A significant similarity exists in the structural parameters for the TCS complex and those for a DCS edge-surface complex that is protonated in the same manner as the optimal DES complex, which could complicate detecting the DCS complex in X-ray absorption spectra.4

show abstract

“…The detection of U−C distances implies carbonate complexes of uranyl to be adsorbed, e.g., as observed for uranyl on montmorillonite at pH 7 under aerobic conditions [35]. Corresponding experiments of uranyl adsorption on gibbsite and kaolinite at even higher pH (Table 1) did not furnish any hints on carbonate complexes as adsorbates [12,30,34,36,39].…”

Section: Resultsmentioning

confidence: 86%

“…In the cluster approach [27,39], a finite part is cut from the surface region and computationally treated as a molecular species. Alternatively, periodic slab models are constructed by stacking of slabs of finite thickness and periodic in two dimensions.…”

Section: Computational Treatmentsmentioning

confidence: 99%

Quantum chemical modeling of uranyl adsorption on mineral surfaces

Kremleva

Krüger

Rösch³

2010

Ract

View full text Add to dashboard Cite

We overview quantum mechanical simulations that model the adsorption of actinide ions at solvated mineral surfaces. Pertinent examples illustrate the status of this emerging field of computational chemistry. In particular, we describe our own studies on uranyl adsorption on kaolinite. Already the few available results, from applications of density functional methods to cluster models or periodic slab models, show that such calculations are a useful complement to experimental investigations. Detailed information at the atomic level from accurate electronic structure calculations on well defined model systems helps to refine current interpretations of the chemical nature of uranyl adsorption species and to discover new features of these interface systems. Results from quantum mechanical simulations also provide a valuable reference for future experimental investigations.

show abstract

The structure of monomeric and dimeric uranyl adsorption complexes on gibbsite: A combined DFT and EXAFS study

Cited by 76 publications

References 61 publications

Sorption of U(VI) at the TiO2–water interface: An in situ vibrational spectroscopic study

Sorption of U(VI) at the TiO2–water interface: An in situ vibrational spectroscopic study

Surface complexation of Pb(II) by hexagonal birnessite nanoparticles

Quantum chemical modeling of uranyl adsorption on mineral surfaces

Contact Info

Product

Resources

About