Moore Emily E, Kocevski Vancho, Juillerat Christian A, Morrison Gregory, Zhao Mingyang, Brinkman Kyle S, Loye Hans-Conrad Zur, Besmann Theodore M
Nuclear Engineering Program, Department of Mechanical Engineering, University of South Carolina, Columbia, SC, 29208, USA.
Department of Chemistry, University of South Carolina, Columbia, SC, 29208, USA.
Sci Rep. 2018 Oct 17;8(1):15294. doi: 10.1038/s41598-018-32903-3.
Formation enthalpies and Gibbs energies of actinide and rare-earth containing SIMs with silicate and germanate frameworks are reported. Volume-based thermodynamics (VBT) techniques complemented by density functional theory (DFT) were adapted and applied to these complex structures. VBT and DFT results were in closest agreement for the smaller framework silicate structure, whereas DFT in general predicts less negative enthalpies across all SIMs, regardless of framework type. Both methods predict the rare-earth silicates to be the most stable of the comparable structures calculated, with VBT results being in good agreement with the limited experimental values available from drop solution calorimetry.
报道了含锕系元素和稀土元素的具有硅酸盐和锗酸盐骨架的结构单元(SIMs)的生成焓和吉布斯自由能。采用基于体积的热力学(VBT)技术并辅以密度泛函理论(DFT),将其应用于这些复杂结构。对于较小的骨架硅酸盐结构,VBT和DFT结果最为吻合,而总体而言,DFT预测所有结构单元的焓值负性较小,与骨架类型无关。两种方法均预测稀土硅酸盐在所计算的可比结构中最为稳定,VBT结果与滴液量热法得到的有限实验值吻合良好。