晶体材料属性的计算和模拟通常基于具有最小自由度数量的周期性排列的单元格，即原胞。Wigner-Seitz单元格及其相应的第一布里渊区是使用最广泛的原胞。这些原胞通常用于晶格振动和传输属性的计算，因为它们的计算成本最低。然而，这类计算，尤其是在复杂晶体中，往往涉及到尴尬的几何形状，其中 Wigner-Seitz 单元格和第一布里渊区在笛卡尔空间中具有不规则、非直观的形状。此外，目前仍不清楚如何利用对称关系使晶格动力学计算在更大的单元格中更有效率。在本工作中，来自美国橡树岭国家实验室的Xun Li等人，提出了一种利用惯用晶胞内原始平移对称性（PTS）的高效动力学来研究晶格动力学和声子输运的方法。基于PTS，他们将原始到惯用单元格的动态方法应用于由非谐相互作用限制的热传输计算中。在惯用几何结构中，这种PTS动力学方法通过在典型传统动力学中隐藏的守恒规则，显著减少准粒子散射相空间，并减少散射矩阵元素计算中的求和次数，从而降低热导率计算的计算成本。作者通过计算三种不同空间群材料的声子输运性质，证明了这种PTS方法的便利性，这三种材料为空间群R3m的GeTe、空间群I2₁3的固体N₂和空间群R-3的铁磁CrCl₃ 。该工作提出的动力学方法能够准确描述传输现象，并且比传统动力学方法在计算上成本更低，这对于研究复杂材料系统中的准粒子相互作用具有重要价值。

Editorial Summary: Primitive to conventional geometry projection——efficient phonon transport calculations

Calculations and simulations of crystalline material properties are typically based on periodically arranged unit cells that contain the smallest number of degrees of freedom, i.e., the primitive unit cell. The most widely used primitive cells are called Wigner-Seitz cells (WSC) and their corresponding first Brillouin zones (FBZ). These are typically used for calculations of lattice vibrational and transport properties because they have the cheapest computational cost. However, such calculations, particularly in complex crystals, often have awkward geometries with WSC and FBZ having irregular, non-intuitive shapes in Cartesian space. In addition, it is not well known how to use symmetry relations to make lattice dynamical calculations more efficient in larger unit cells. In this work, Xun Li et al. from Oak Ridge National Laboratory, explored the lattice dynamics and phonon transport using an efficient dynamic method that utilizes primitive translational symmetry (PTS) within conventional cells. They applied this primitive to conventional cell dynamic method based on PTS to thermal transport calculations limited by anharmonic interactions. In conventional geometries, this PTS dynamic method significantly reduces the computational cost of thermal conductivity calculations by reducing the quasiparticle scattering phase space through a conservation rule that is hidden in typical conventional dynamics and reducing the number of summations in scattering matrix element calculations. They demonstrated the convenience of this PTS method by calculating phonon transport properties for three materials from different space groups: GeTe with space group R3m, solid N₂ with space group I2₁3, and ferromagnetic CrCl₃ with space group R-3. The proposed dynamics accurately describes transport phenomena and costs significantly less computationally compared to conventional dynamics, which is valuable for studying quasiparticle interactions in complex material systems.