Mn-based Heusler alloys ‘MnY₂Z (Z= (Al and Si)) have ‘L2₁’ crystal structure at the ambient condition of temperature and pressure. MnY₂Z have a high melting temperature, shows half-metallic character and shape memory effects where numerous of its applications takes place. In this report, theoretical investigations of the phonon properties of MnY₂Z in the cubic phase has been investigated by using density functional theory followed by density functional perturbation theory to comprehend the role of phonons in these alloys. In these calculations, zone center phonon frequency, phonon modes in symmetric directions and phonon density of states are investigated for these alloys. The phonon modes are found to be positive in all symmetric directions indicate the stability of the present alloys in the L2₁ crystal structure. Additionally, Raman and infrared phonon modes have also been identified for each alloy. The investigated results are interpreted with other existing similar type of Heusler alloys.

Mn基Heusler合金'MnY ₂ Z（Z =（Al和Si））在温度和压力的环境条件下具有'L2 ₁ '晶体结构。MnY ₂ Z具有很高的熔化温度，在许多应用场合中表现出半金属特性和形状记忆效应。在本报告中，对MnY ₂声子性质的理论研究通过使用密度泛函理论，然后使用密度泛函微扰理论来研究立方相中的Z，以了解声子在这些合金中的作用。在这些计算中，研究了这些合金的区域中心声子频率，对称方向的声子模和状态的声子密度。发现声子模在所有对称方向上为正，表明本合金在L _{2 1}晶体结构中的稳定性。此外，还为每种合金确定了拉曼和红外声子模式。研究结果用其他现有的相似类型的Heusler合金来解释。