Elucidating Ionic Correlations Beyond Simple Charge Alternation in Molten MgCl2–KCl Mixtures
Abstract
The development of technologies for nuclear reactors based on molten salts has seen a big resurgence. The success of thermodynamic models for these hinges in part on our ability to predict at the atomistic level the behavior of pure salts and their mixtures under a range of conditions. In this letter, we present high-energy X-ray scattering experiments and molecular dynamics simulations that describe the molten structure of mixtures of MgCl2 and KCl. As one would expect, KCl is a prototypical salt in which structure is governed by simple charge alternation. In contrast, MgCl2 and its mixtures with KCl display more complex correlations including intermediate-range order and the formation of Cl–-decorated Mg2+ chains. A thorough computational analysis suggests that intermediate-range order beyond charge alternation may be traced to correlations between these chains. Here, an analysis of the coordination structure for Mg2+ ions paints a more complex picture than previously understood, with multiple accessible states of distinct geometries.
- Authors:
-
- Univ. of Iowa, Iowa City, IA (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
- Osaka Univ. (Japan)
- Publication Date:
- Research Org.:
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II); Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Energy Frontier Research Centers (EFRC) (United States). Molten Salts in Extreme Environments (MSEE); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Oak Ridge Leadership Computing Facility (OLCF)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Nuclear Physics (NP); Japan Society for the Promotion of Science (JSPS)
- OSTI Identifier:
- 1593246
- Alternate Identifier(s):
- OSTI ID: 1593254; OSTI ID: 1605682; OSTI ID: 1606773
- Report Number(s):
- BNL-213564-2020-JAAM; BNL-213557-2020-JAAM
Journal ID: ISSN 1948-7185
- Grant/Contract Number:
- SC0012704; AC05-00OR22725; AC02-06CH11357; JP17J01006
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Physical Chemistry Letters
- Additional Journal Information:
- Journal Volume: 10; Journal Issue: 24; Journal ID: ISSN 1948-7185
- Publisher:
- American Chemical Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; KCl; MgCl2; Simulations; X-ray Scattering; molten chloride salts; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS
Citation Formats
Wu, Fei, Roy, Santanu, Ivanov, Alexander S., Gill, Simerjeet K., Topsakal, Mehmet, Dooryhee, Eric, Abeykoon, Milinda, Kwon, Gihan, Gallington, Leighanne C., Halstenberg, Phillip, Layne, Bobby, Ishii, Yoshiki, Mahurin, Shannon M., Dai, Sheng, Bryantsev, Vyacheslav S., and Margulis, Claudio J. Elucidating Ionic Correlations Beyond Simple Charge Alternation in Molten MgCl2–KCl Mixtures. United States: N. p., 2019.
Web. doi:10.1021/acs.jpclett.9b02845.
Wu, Fei, Roy, Santanu, Ivanov, Alexander S., Gill, Simerjeet K., Topsakal, Mehmet, Dooryhee, Eric, Abeykoon, Milinda, Kwon, Gihan, Gallington, Leighanne C., Halstenberg, Phillip, Layne, Bobby, Ishii, Yoshiki, Mahurin, Shannon M., Dai, Sheng, Bryantsev, Vyacheslav S., & Margulis, Claudio J. Elucidating Ionic Correlations Beyond Simple Charge Alternation in Molten MgCl2–KCl Mixtures. United States. doi:10.1021/acs.jpclett.9b02845.
Wu, Fei, Roy, Santanu, Ivanov, Alexander S., Gill, Simerjeet K., Topsakal, Mehmet, Dooryhee, Eric, Abeykoon, Milinda, Kwon, Gihan, Gallington, Leighanne C., Halstenberg, Phillip, Layne, Bobby, Ishii, Yoshiki, Mahurin, Shannon M., Dai, Sheng, Bryantsev, Vyacheslav S., and Margulis, Claudio J. Mon .
"Elucidating Ionic Correlations Beyond Simple Charge Alternation in Molten MgCl2–KCl Mixtures". United States. doi:10.1021/acs.jpclett.9b02845. https://www.osti.gov/servlets/purl/1593246.
@article{osti_1593246,
title = {Elucidating Ionic Correlations Beyond Simple Charge Alternation in Molten MgCl2–KCl Mixtures},
author = {Wu, Fei and Roy, Santanu and Ivanov, Alexander S. and Gill, Simerjeet K. and Topsakal, Mehmet and Dooryhee, Eric and Abeykoon, Milinda and Kwon, Gihan and Gallington, Leighanne C. and Halstenberg, Phillip and Layne, Bobby and Ishii, Yoshiki and Mahurin, Shannon M. and Dai, Sheng and Bryantsev, Vyacheslav S. and Margulis, Claudio J.},
abstractNote = {The development of technologies for nuclear reactors based on molten salts has seen a big resurgence. The success of thermodynamic models for these hinges in part on our ability to predict at the atomistic level the behavior of pure salts and their mixtures under a range of conditions. In this letter, we present high-energy X-ray scattering experiments and molecular dynamics simulations that describe the molten structure of mixtures of MgCl2 and KCl. As one would expect, KCl is a prototypical salt in which structure is governed by simple charge alternation. In contrast, MgCl2 and its mixtures with KCl display more complex correlations including intermediate-range order and the formation of Cl–-decorated Mg2+ chains. A thorough computational analysis suggests that intermediate-range order beyond charge alternation may be traced to correlations between these chains. Here, an analysis of the coordination structure for Mg2+ ions paints a more complex picture than previously understood, with multiple accessible states of distinct geometries.},
doi = {10.1021/acs.jpclett.9b02845},
journal = {Journal of Physical Chemistry Letters},
number = 24,
volume = 10,
place = {United States},
year = {2019},
month = {11}
}
Web of Science