Universität zu Köln

Chattopadhyay, Rajorshi ORCID: 0009-0008-3812-3731 and Jahn, Sandro ORCID: 0000-0002-2137-8833 (2025). Structural and thermodynamic properties of La3+ in chloride-bearing hydrothermal fluids – insights from a new ab initio-based polarizable force field. Journal of Molecular Liquids, 437. pp. 1-10. Elsevier. ISSN 0167-7322

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Abstract

[Artikel-Nr.: 128546] Rare earth elements (REEs) are an important group of elements both geologically and economically. The ability of hydrothermal fluids to mobilize REEs in natural, ore-forming environments depends on the chemical composition and the presence of suitable ligands such as chloride and fluoride. Here, we use molecular dynamics (MD) simulations to study the molecular structure and thermodynamic stability of La species in Cl-bearing hydrothermal fluids. We develop a new polarizable force field for this system optimized by reference to density functional theory (DFT) calculations. The structural and thermodynamic data obtained with the new potential using the well-tempered metadynamics (WMetaD) technique reproduce experimental and ab initio MD simulation data well. Polarization effects are shown to be essential for predicting realistic association and stability constants, which were not achieved with simpler non-polarizable interaction potentials. Simulations with different box sizes indicate that the effects of simulation box sizes on calculated thermodynamic quantities are almost negligible at high temperatures.

Item Type:	Article
Creators:	Creators Email ORCID ORCID Put Code Chattopadhyay, Rajorshi UNSPECIFIED https://orcid.org/0009-0008-3812-3731 UNSPECIFIED Jahn, Sandro UNSPECIFIED https://orcid.org/0000-0002-2137-8833 UNSPECIFIED
URN:	urn:nbn:de:hbz:38-810182
Identification Number:	10.1016/j.molliq.2025.128546
Journal or Publication Title:	Journal of Molecular Liquids
Volume:	437
Page Range:	pp. 1-10
Number of Pages:	10
Date:	November 2025
Publisher:	Elsevier
ISSN:	0167-7322
Language:	English
Faculty:	Faculty of Mathematics and Natural Sciences
Divisions:	Faculty of Mathematics and Natural Sciences > Department of Geosciences > Institute of Geology and Mineralog
Subjects:	Earth sciences Geography and travel
Uncontrolled Keywords:	Keywords Language Rare earth elements ; Hydrothermal fluids ; Speciation ; Reaction thermodynamics ; Molecular dynamics ; Enhanced sampling techniques ; Polarizable force field English
['eprint_fieldname_oa_funders' not defined]:	Publikationsfonds UzK
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/81018