A coupled key phase diagram study and critical evaluation and optimization of all available experimental data of the Li₂O–MgO–SiO₂ system was performed to obtain a set of Gibbs energy functions to reproduce all the reliable phase equilibria and thermodynamic data. Differential scanning calorimetry measurements and equilibration/quenching experiments were performed in the Li₂SiO₃–MgO and Li₄SiO₄–Mg₂SiO₄ sections, respectively, using sealed Pt capsules to prevent the volatile loss of Li. According to the present experimental results, Li₂MgSiO₄ is the only compound present in the Li₄SiO₄–Mg₂SiO₄ isopleth, which shows a peritectic melting at 1465 ± 6°C (1738 ± 6 K). The Modified Quasichemical Model, which considers short-range ordering in the melt, was employed to describe the thermodynamic properties of the liquid phase. The Li₄SiO₄–Li₂MgSiO₄ and Mg₂SiO₄-rich solid solutions were modeled using the Compound Energy Formalism.

中文翻译：

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Li2O–MgO–SiO2系统的耦合实验相图研究和热力学优化

对Li ₂ O–MgO–SiO ₂系统的所有可用实验数据进行了关键相图研究以及关键评估和优化，以获取一组吉布斯能量函数，以再现所有可靠的相平衡和热力学数据。使用密封的Pt胶囊分别在Li ₂ SiO ₃ -MgO和Li ₄ SiO ₄ -Mg ₂ SiO ₄切片中进行差示扫描量热法测量和平衡/淬灭实验，以防止Li的挥发损失。根据目前的实验结果，Li ₂ MgSiO ₄是唯一存在于Li中的化合物₄ SiO ₄ -Mg ₂ SiO _4等静压，在1465±6°C（1738±6 K）下显示出包晶熔体。考虑到熔体中的短程有序化的改进的准化学模型被用来描述液相的热力学性质。使用复合能量形式主义对富含Li ₄ SiO ₄ -Li ₂ MgSiO ₄和Mg ₂ SiO _4的固溶体进行建模。