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oai:figshare.com:article/34033222 2026-09-30T14:38:35Z category_1 category_915 category_16 category_873 portal_63 item_type_6 month_year_09_2026

Comparative Assessment of Exchange-Correlation Functionals for the Structural, Thermodynamic, and Transport Properties of Liquid Lithium Romakanta Bhattarai (10832656) Thomas F. Fuerst (3137847) Stephen T. Lam (12204944) Biophysics Physical Sciences not elsewhere classified Physiology Chemical Sciences not elsewhere classified making reliable first diffusion activation energy balanced overall agreement advanced energy applications 77 × 10 75 × 10 24 × 10 18 × 10 thermal expansion coefficient 62 ± 1 available experimental data 0 )] functionals results provide guidance accurate aimd modeling 3 </ sup d3 predicts 22 ten xc functionals 42 ± 2 thermal response ± 8 ± 7 revpbe predicts experimental value functionals considered xc functional wide range whereas pbe tritium breeder transport properties tested d3 significant impact revpbe provides results show relative accuracy predicted properties per atom operating conditions important material higher densities heat capacity gga ), facing material Liquid lithium (Li) is an important material for advanced energy applications, particularly fusion energy systems, where it can serve as a tritium breeder, coolant, and plasma-facing material. The development of these technologies requires accurate predictions of liquid-state properties over a wide range of temperatures and operating conditions, making reliable first-principles simulations increasingly important. However, the performance and relative accuracy of commonly used density functional theory (DFT) exchange-correlation (XC) functionals for liquid Li have not been systematically benchmarked against experiment. In this work, we use ab initio molecular dynamics (AIMD) simulations to evaluate structural, thermodynamic, and transport properties of liquid Li. Structural properties probe local atomic ordering, thermodynamic properties, including density, bulk modulus, thermal expansion coefficient, and heat capacity, probe the liquid equation of state and thermal response, and self-diffusion probes atomic dynamics. Ten XC functionals are benchmarked, including local-density approximation (LDA), generalized gradient approximation (GGA), and zero-damping D3-corrected [D3(0)] functionals, and the results are systematically compared with available experimental data. The results show that the choice of XC functional has a significant impact on the predicted properties. At 1000 K, revPBE predicts an equilibrium volume of 25.00 ų per atom, compared with the experimental value of 25.09 ų per atom, whereas PBE-D3 predicts 22.06 ų per atom. The tested D3-corrected functionals generally predict smaller equilibrium volumes, higher densities and bulk moduli, and lower thermal expansion coefficients than experiment, indicating excessive binding within the tested D3-corrected framework. Among the functionals considered, revPBE provides the most balanced overall agreement with experiment, including a thermal expansion coefficient of 2.75 × 10^–4 K^–1 ± 8.24 × 10^–6 K^–1, compared with the experimental value of 2.77 × 10^–4 ± 7.18 × 10^–6 K^–1, and a self-diffusion activation energy of 9.42 ± 2.03 kJmol^–1, compared with 9.62 ± 1.26 kJmol^–1. These results provide guidance for selecting experimentally anchored XC functionals for accurate AIMD modeling of liquid Li. 2026-09-30T00:00:00Z Text Journal contribution 10.1021/acsomega.6c08835.s001 https://figshare.com/articles/journal_contribution/Comparative_Assessment_of_Exchange-Correlation_Functionals_for_the_Structural_Thermodynamic_and_Transport_Properties_of_Liquid_Lithium/34033222 CC BY-NC 4.0