Crystal structure and magnetic properties of glaserite-type Ba₃MnSi₂O₈ were investigated using variable temperature neutron powder diffraction and magnetometry. At room temperature the composition is hexagonal and the crystal structure is best described by the P-3m1 space group (a~ 5.7 Å, c~ 7.3 Å) with the apical oxygen atom modelled on a split site. On cooling below ~ 250 K the structure undergoes a phase transition into a monoclinic C2/c form (√3a_hex, a_hex, 2c_hex, β~ 90°). Analysing diffraction data in terms of symmetry-adapted distortion modes suggests that the transition is primarily driven by increasing in-plane displacements of O1, which in turn results in the coupled tilting of [SiO₄] and [MnO₆] octahedra and in-plane displacements of Ba1 atoms. Magnetic susceptibility measurements and neutron powder diffraction data show no evidence for long-range magnetic ordering down to 1.6 K, although the development of magnetic diffuse scattering suggests that a magnetic transition may take place at lower temperature.

利用变温中子粉末衍射和磁强计研究了方晶型Ba ₃ MnSi ₂ O _8的晶体结构和磁性。在室温下，其组成为六边形，晶体结构最好用P -3 m 1空间群（a〜5.7Å，c〜7.3Å）描述，其顶部氧原子模拟在分裂位点上。下面冷却〜250 k中结构经历相转变到单斜晶ç 2 / ç形式（√3a_十六进制，一个_十六进制，2C_六角，β〜90°）。根据对称变形模式分析衍射数据表明，转变主要是由O1的面内位移增加引起的，这反过来导致[SiO ₄ ]和[MnO ₆ ]八面体与面内耦合倾斜Ba1原子的位移。磁化率测量和中子粉末衍射数据没有显示低至1.6 K的远距离磁有序证据，尽管磁扩散散射的发展表明在较低温度下可能发生磁跃迁。