ORALS

SESSION: GeochemistryTueAM-R8	Navrotsky International Symposium (2nd Intl. Symp. on Geochemistry for Sustainable Development)
Tue. 28 Nov. 2023 / Room: Coral Reef
Session Chairs: Wenhao Sun; Manisha Rane-Fondacaro; Session Monitor: TBA

11:35: [GeochemistryTueAM01] OS Plenary
THE MATERIALS CYCLE, SUSTAINABILITY, AND THERMODYNAMICS
Alexandra Navrotsky¹ ; ¹Arizona State University, Phoenix, United States;
Paper Id: 58 [Abstract]

Though the abundances of elements in our galaxy arise from nuclear physics, the materials they form in planetary systems reflect their chemistry, with complex reactions involving gases, liquids, fluids, melts and solids. On Earth we have inherited, from billions of years of geologic processes, mostly at high temperature and pressure, a suite of rocks and minerals which are the source of all materials we make and use. After use, the elements are eventually returned to the Earth as “waste” or “contamination”. This cycle of mining, processing, use, and disposition can be referred to as “cradle to grave” technology. More sustainable technology, involving reuse of “waste” in technology, is sometimes called “cradle to cradle”. In either case, the feasibility of each step is determined by thermodynamics, and its rate by kinetics. Using rare earths and actinides as examples, this lecture addresses thermodynamic constraints on mining, extraction, separation, fabrication, corrosion and disposal. Current interest in space exploration and planetary missions, as well as the discovery of myriads of exotic and highly variable exoplanets, place these thermodynamic questions in a much broader context for materials of the universe.

SESSION: GeochemistryTueAM-R8	Navrotsky International Symposium (2nd Intl. Symp. on Geochemistry for Sustainable Development)
Tue. 28 Nov. 2023 / Room: Coral Reef
Session Chairs: Wenhao Sun; Manisha Rane-Fondacaro; Session Monitor: TBA

12:50: [GeochemistryTueAM04] OS
ENTHALPIES OF MIXING FOR ALLOYS LIQUID BELOW ROOM TEMPERATURE DETERMINED BY OXIDATIVE SOLUTION CALORIMETRY
Michael Bustamante¹ ; Alexandra Navrotsky² ; Kristina Lilova³ ; Jean-Philippe Harvey⁴ ; Oishi Kentaro⁵ ; ¹Arizona State U., Tempe, United States; ²Arizona State University, Phoenix, United States; ³ARIZONA STATE UNIVERSITY, Tempe, United States; ⁴Chemical Engineering Department, CRCT Polytechnique Montréal, Montréal, Canada; ⁵Chemical Engineering Department, Montréal, Canada;
Paper Id: 31 [Abstract]

Fusible alloys, and gallium-based liquid metal alloys (Ga-LMA) in particular, have applications in soft robotics, microelectronics, self-healing battery components, and 2D materials synthesis, making the study of their thermodynamic properties critical to improvement and development of hybrid materials. To determine the enthalpies of formation/mixing of the binary Ga-In, the ternary Ga-In-Sn, and the quaternary Ga-In-Sn-Zn eutectics, a novel experimental calorimetric technique based on oxidative solution calorimetry was developed. The experimental results for the binary alloy are consistent with previous data obtained by direct reaction and solution calorimetry, demonstrating the viability and precision of the experimental technique, which is applicable to a large variety system that are liquid at or below room temperature. The heats of mixing in the ternary and quaternary systems represent the first reported experimental values. Both the standard geometrical models and FactSage were used to define enthalpy analogs for these systems which agreed with the experimental data, providing a foundation to analyze the thermodynamics of other unknown Ga-based alloys.

SESSION: GeochemistryTuePM1-R8	Navrotsky International Symposium (2nd Intl. Symp. on Geochemistry for Sustainable Development)
Tue. 28 Nov. 2023 / Room: Coral Reef
Session Chairs: Megan Householder; Zi-Kui Liu; Session Monitor: TBA

14:05: [GeochemistryTuePM105] OS
MEASUREMENT OF NANOPARTICLE SURFACE ENERGIES WITH APPLICATION TO NUCLEATION AND CONDENSATION IN EXOPLANET ATMOSPHERES
Megan Householder¹ ; Alexandra Navrotsky¹ ; Kristina Lilova² ; ¹Arizona State University, Phoenix, United States; ²ARIZONA STATE UNIVERSITY, Tempe, United States;
Paper Id: 52 [Abstract]

Exoplanets orbit stars other than our own sun. Aerosols are a prominent feature of exoplanet atmospheres, sometimes obscuring the spectral determination of atmospheric gas composition [1]. Hot Jupiters are studied because they are the hottest of exoplanets, so emit the most radiation and therefore, give the most spectral information on exoplanets. Because it is not yet possible to definitively determine aerosol composition and formation through astronomical observations, it is important to model aerosol production accurately [2]. A key factor in the determination of nucleation and condensation rate is the surface energy of the nucleating material [3]. High surface energy materials, such as forsterite, will nucleate much more slowly compared to lower surface energy materials, such as sulfides. Despite their importance, few surface energies of rock-forming minerals have been measured [4]. In this work, surface energies were measured using oxide melt solution calorimetry of materials with different surface areas for likely exoplanet atmosphere condensates including zinc sulfide (ZnS) [5] and enstatite (MgSiO3), with other measured surface energies taken from experimental rather than estimated data. This work inputs the accurate measured surface energy data to calculate a model of nucleation rates for each of the proposed cloud species of a hot Jupiter exoplanet with atmospheric metallicity of 10x solar, a total atmospheric pressure of 10 bar and a saturation ratio of 10. These corrected surface energy values show drastically different nucleation rates for a variety of condensates in the atmospheres, which lead to different atmospheric compositions of these exoplanets than previous models.

References:
[1] D. Adams, P. Gao, I. de Pater, and C. V. Morley, “Aggregate Hazes in Exoplanet Atmospheres,” Astrophys. J., vol. 874, no. 1, p. 61, Mar. 2019, doi: 10.3847/1538-4357/ab074c.
[2] A. Navrotsky and M. Householder, “New worlds, new chemistry, new ceramics,” Int. J. Ceram. Eng. Sci., vol. 3, no. 6, pp. 252–266, Nov. 2021, doi: 10.1002/CES2.10104.
[3] P. Gao, M. S. Marley, and A. S. Ackerman, “Sedimentation Efficiency of Condensation Clouds in Substellar Atmospheres,” Astrophys. J., vol. 855, no. 2, p. 86, Mar. 2018, doi: 10.3847/1538-4357/aab0a1.
[4] S. Chen and A. Navrotsky, “Calorimetric study of the surface energy of forsterite,” Am. Mineral., vol. 95, no. 1, pp. 112–117, 2010, doi: 10.2138/am.2010.3339.
[5] T. Subramani, K. Lilova, M. Householder, S. Yang, J. Lyons, and A. Navrotsky, “Surface energetics of wurtzite and sphalerite polymorphs of zinc sulfide and implications for their formation in nature,” Geochim. Cosmochim. Acta, vol. 340, pp. 99–107, 2022, doi: 10.1016/j.gca.2022.11.003.

SESSION: GeochemistryTuePM1-R8	Navrotsky International Symposium (2nd Intl. Symp. on Geochemistry for Sustainable Development)
Tue. 28 Nov. 2023 / Room: Coral Reef
Session Chairs: Megan Householder; Zi-Kui Liu; Session Monitor: TBA

15:20: [GeochemistryTuePM108] OL
THERMODYNAMIC INSIGHT INTO COMPLEX OXIDES OF MARTIAN RELEVANCE
Christophe Drouet¹ ; Alexandra Navrotsky² ; ¹CIRIMAT Institute, Toulouse, France; ²Arizona State University, Phoenix, United States;
Paper Id: 458 [Abstract]

A series of complex oxides have, along the years, raised interest in the field of Martian mineralogy. This includes compounds of the Jarosite, Apatite and Jahnsite large groups of minerals. Whereas some of them, typically F- and Cl-apatites have been identified on the red planet, the presence of some other phases like Jarosites and more recently Jahnsites have been suspected to occur on Mars without actual proofs of their presence. Whether for confirming or invalidating the possible presence of such oxide phases on the surface of Mars, or for better assessing their eventual evolution in the Martian atmosphere and surface conditions, it is primordial to have access to thermodynamic data – as much reliable as possible – yet sometimes scarcely available. Thus, in this long run work along the years, we have launched synthesis procedures with the view to prepare relevant compositions of these three families of minerals ore relevance to Mars mineralogy, and explored their thermodynamics through oxide-melt solution calorimetry when possible, and via the ThermAP (Applied Predictive Thermodynamics) simplified predictive approach. In this presentation, the main milestones and findings of this research will be reminded, and the main thermodynamic trends will be highlighted with regards to Jarosites, Apatites and Jahnsites.

References:
[1] A. Navrotsky, F.L. Forray, C. Drouet, Jarosite stability on Mars, Icarus 176 (2005) 250-253.
[2] C. Drouet, A Comprehensive Guide to Experimental and Predicted Thermodynamic Properties of Phosphate Apatite Minerals in view of Applicative Purposes, The Journal of Chemical Thermodynamics, 81 (2015) 143-159 (= initiation of the ThermAP model).
[3] C. Drouet, Applied predictive thermodynamics (ThermAP). Part 2. Apatites containing Ni2+, Co2+, Mn2+, or Fe2+ ions, The Journal of Chemical Thermodynamics, 136 (2019) 182-189 (= extension of the ThermAP model).
[4] Fau et al., Time-resolved Raman and luminescence spectroscopy of synthetic REE-doped hydroxylapatites and natural apatites, The American Mineralogist, 107(7) (2022) 1341-1352.
[5] C. Drouet, M. Loche, S. Fabre, P.Y. Meslin, On the occurrence of Jahnsite/Whiteite phases on Mars: a thermodynamic study, The American Mineralogist, 107(9) (2022) 1807-1817.

SESSION: GeochemistryTuePM2-R8	Navrotsky International Symposium (2nd Intl. Symp. on Geochemistry for Sustainable Development)
Tue. 28 Nov. 2023 / Room: Coral Reef
Session Chairs: Qijun Hong; Fabienne Trolard; Session Monitor: TBA

17:15: [GeochemistryTuePM212] OS
HIGH TEMPERATURE THERMOCHEMISTRY FROM EXPERIMENT, AB INITIO, AND MACHINE LEARNING
Sergey Ushakov¹ ; Qijun Hong¹ ; Alexandra Navrotsky² ; ¹Arizona State University, Tempe, United States; ²Arizona State University, Phoenix, United States;
Paper Id: 14 [Abstract]

The measurements, computations, and predictions of high temperature thermodynamic properties are of interest to geoscience, material science, and engineering. The experimental techniques to provide structural and thermodynamic data above 1500 °C were developed in Navrotsky’s group for over 10 years. This resulted in the first demonstration of crystal structure refinements on laser-heated aerodynamically levitated samples using synchrotron X-ray and neutron diffraction and drop calorimetry measurements with splittable nozzle aerodynamic levitator [1]. High temperature diffraction provides experimental data on thermal expansion, atomic displacement parameters, and volume change in phase transformations. Drop calorimetry on levitated samples provides enthalpy of fusion. These data can also be obtained from ab initio molecular dynamic computations. The experimentally benchmarked computations can provide reliable data on high temperature heat capacities [2]. Melting or decomposition temperature is a widely used thermodynamic property. Experimental measurements and ab initio computations require time, resources, and expertise. The machine learning model has been developed and trained on ~10,000 experimental and ab initio values of melting points for congruently melting compounds. It has been applied to predict melting or decomposition temperatures of ~5,000 known mineral species which revealed new correlations with the time of Late Heavy Bombardment event and structural complexity index [3]. The model is publicly accessible via the web interface on Hong’s group website for the prediction of melting temperatures within seconds [4].

References:
[1] S. V. Ushakov, P. S. Maram, D. Kapush, A. J. Pavlik, III, M. Fyhrie, L. C. Gallington, C. J. Benmore, R. Weber, J. C. Neuefeind, J. W. McMurray, A. Navrotsky, Adv. Appl. Ceram. 117, s82-s89 (2018) https://doi.org/10.1080/17436753.2018.1516267. [2] Q.-J. Hong, A. van de Walle, S. V. Ushakov, A. Navrotsky, Calphad 79, 102500 (2022) https:/doi.org/10.1016/j.calphad.2022.102500. [3] Q.-J. Hong, S. V. Ushakov, A. van de Walle, A. Navrotsky, PNAS 119, e2209630119 (2022) https://doi.org/10.1073/pnas.2209630119. [4] https://faculty.engineering.asu.edu/hong/melting-temperature-predictor/