Crossover of cation partitioning in olivines: a combination of ab initio and Monte Carlo study

Chatterjee, Swastika; Bhattacharyya, Sirshendu; Sengupta, Surajit; Saha‐Dasgupta, Tanusri

doi:10.1007/s00269-010-0401-4

Cited by 11 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is rather surprising, as one would expect that the Mg-Al disorder should significantly increase with increasing temperature, as observed for other minerals such as spinel (e.g., Princivalle et al 1999): for instance, in [4] (Mg 1−x Al x ) [6] (Mg x Al 2−x )O 4 , the Mg-Al disorder, expressed as inversion degree x, increases from 0.18 to 0.29 with increasing temperature from 600 to 1100 °C, respectively (Andreozzi et al 2000). However, an increase in cation ordering with increasing temperature was recently also observed in olivine (Heinemann et al 2006;Chatterjee et al 2011). The reason that the cation distribution of dravite remains almost unchanged after thermal treatment may be ascribed to extensive local clustering of specific cations and anions that can occur in tourmaline (e.g., Taylor et al 1995;Skogby et al 2012) due to the effect of the local valencesum rule (e.g., Hawthorne 1996; Bosi 2011).…”

Section: Infrared Spectroscopymentioning

confidence: 95%

Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study

2016

View full text Add to dashboard Cite

Section: Infrared Spectroscopymentioning

confidence: 95%

Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study

2016

View full text Add to dashboard Cite

“…The Mg and Fe atoms are coordinated with six oxygen atoms and occupy two different sites in the structure, namely, M1 and M2. The M1 oxygen atom is held in a distorted octahedron with two O1, two O2, and two O3 atoms held at the apexes connected by two Si-tetrahedral edges, while M2 is in a less-distorted octahedron surrounded by one O1, one O2, and four O3 atoms connected to one tetrahedral edge and three tetrahedral apexes …”

Section: Olivine Crystal Structurementioning

confidence: 99%

“…The M1 oxygen atom is held in a distorted octahedron with two O1, two O2, and two O3 atoms held at the apexes connected by two Si-tetrahedral edges, while M2 is in a less-distorted octahedron surrounded by one O1, one O2, and four O3 atoms connected to one tetrahedral edge and three tetrahedral apexes. 24 In this work, we focus on the study of the interaction of H 2 O with the Mg end member of olivine, i.e., forsterite (Mg 2 SiO 4 ), containing Mg atoms in both M1 and M2 sites. The forsterite crystal structure is shown in Figure 1 with the M1 and M2 sites indicated as Mg1 and Mg2, respectively.…”

Section: ■ Olivine Crystal Structurementioning

confidence: 99%

Interaction between Olivine and Water Based on Density Functional Theory Calculations

2013

View full text Add to dashboard Cite

The understanding of the interaction of water with mineral surfaces is fundamental for the description of solid−liquid interface reactions such as adsorption and desorption of solutes in natural and industrial systems. First-principles calculations can aid in the understanding of these interactions at the molecular level, allowing to formulate mechanistic laws of reaction. In this work, the adsorption of water (H 2 O) on forsteritic olivine (Mg 2 SiO 4 ) is studied on the stoichiometric (100) surface using density functional theory (DFT) based electronic structure calculations to predict stability and reactivity of this surface under atmospheric and hydrothermal conditions. The structure and the energetics were analyzed for H 2 O interacting at different reactive surface sites comprising magnesium, silicon, and oxygen atoms showing that H 2 O can be adsorbed molecularly, dissociatively, or in some combination of the two. Ab initio thermodynamics was employed to extend the first-principles DFT calculations at 0 K in vacuum to atmospheric and hydrothermal conditions providing predictions of the changes in surface stability as a function of temperature and pressure. The type of interaction was analyzed through the surface energy, Bader charge analysis, and the projected density of state (PDOS) of the most stable hydroxylated surface over a wide range of temperatures. This analysis shows that the most stable configuration is the adsorption of two water molecules on two surface sites leading to the formation of a hydronium ion, H 3 O + , bridging two Mg1 atoms and elongating their bonds with the surrounding surface oxygen atoms and a H + binding to a Si atom. Bader charge and density of states analyses indicate that upon interaction significant charge is lost from the surface atoms toward the water molecule groups, suggesting that the hydronium ion is chemisorbed at the Mg surface atoms resulting in reduced stability compared to the Si atom. Finally, the coverage effect up to two layers of water molecules (20 H 2 O/nm 2 ) was investigated to validate our calculations. Below 6 H 2 O/nm 2 , our calculations agree with previous DFT studies available at low coverage predicting that water dissociates at the most reactive sites. At higher coverage, our energetics agree with the experimental data from calorimetric measurements and show that at the most stable hydrated surface water can both dissociate and be molecularly adsorbed, thereby creating a hydrogen-bonding network involving the first and the second water layer.

show abstract

“…These defects were anticipated given the high levels of Mg/Fe mixing in the thermodynamically stable form of MgFeSiO 4 . [38][39][40] This type of defect has been reported to cause blocking of the 1D migration pathways in olivine LiFePO 4 .…”

mentioning

confidence: 99%

“…Computer simulations have been used to investigate a range of materials for lithium and sodium batteries. 40,42,[56][57][58][59] Density functional theory (DFT) calculations were performed using a plane wave basis set implemented in the VASP code.…”

mentioning

confidence: 99%

MgFeSiO₄ as a potential cathode material for magnesium batteries: ion diffusion rates and voltage trends

2017

View full text Add to dashboard Cite

Developing rechargeable magnesium batteries has become an area of growing interest as an alternative to lithium-ion batteries largely due to their potential to offer increased energy density from the divalent charge of the Mg ion. Unlike the lithium silicates for Li-ion batteries, MgFeSiO 4 can adopt the olivine structure as observed for LiFePO 4 . Here we combine advanced modelling techniques based on energy minimization, molecular dynamics (MD) and density functional theory to explore the Mg-ion conduction, doping and

show abstract

Crossover of cation partitioning in olivines: a combination of ab initio and Monte Carlo study

Cited by 11 publications

References 22 publications

Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study

Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study

Interaction between Olivine and Water Based on Density Functional Theory Calculations

MgFeSiO₄ as a potential cathode material for magnesium batteries: ion diffusion rates and voltage trends

Contact Info

Product

Resources

About

Crossover of cation partitioning in olivines: a combination of ab initio and Monte Carlo study

Cited by 11 publications

References 22 publications

Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study

Thermal stability of extended clusters in dravite: a combined EMP, SREF and FTIR study

Interaction between Olivine and Water Based on Density Functional Theory Calculations

MgFeSiO4 as a potential cathode material for magnesium batteries: ion diffusion rates and voltage trends

Contact Info

Product

Resources

About

MgFeSiO₄ as a potential cathode material for magnesium batteries: ion diffusion rates and voltage trends