We report the successful growth of high-quality single crystals of Sr_0.94Mn_0.86Te_1.14O₆ (SMTO) using a self-flux method. The structural, electronic, and magnetic properties of SMTO are investigated by neutron powder diffraction (NPD), single-crystal X-ray diffraction (SCXRD), thermodynamic, and nuclear magnetic resonance techniques in conjunction with density functional theory calculations. NPD unambiguously determined octahedral (trigonal antiprismatic) coordination for all cations with the chiral space group P312 (no. 149), which is further confirmed by SCXRD data. The Mn and Te elements occupy distinct Wyckoff sites, and minor anti-site defects were observed in both sites. X-ray photoelectron spectroscopy reveals the existence of mixed valence states of Mn in SMTO. The magnetic susceptibility and specific heat data evidence a weak antiferromagnetic order at T_N = 6.6 K. The estimated Curie–Weiss temperature θ_CW = −21 K indicates antiferromagnetic interaction between Mn ions. Furthermore, both the magnetic entropy and the ¹²⁵Te nuclear spin–lattice relaxation rate showcase that short-range spin correlations persist well above the Néel temperature. Our work demonstrates that Sr_0.94(2)Mn_0.86(3)Te_1.14(3)O₆ single crystals realize a noncentrosymmetric triangular antiferromagnet.

中文翻译：

---

非中心对称 Sr0.94Mn0.86Te1.14O6 单晶的三角形磁体

我们报告了使用自熔法成功生长高质量 Sr _0.94 Mn _0.86 Te _1.14 O _{6 (SMTO) 单晶。}通过中子粉末衍射 (NPD)、单晶 X 射线衍射 (SCXRD)、热力学和核磁共振技术，结合密度泛函理论计算，研究了 SMTO 的结构、电子和磁性特性。NPD 明确确定了具有手性空间群P的所有阳离子的八面体（三角反棱柱）配位312（编号 149），SCXRD 数据进一步证实了这一点。Mn 和 Te 元素占据不同的 Wyckoff 位置，并且在两个位置都观察到轻微的反位置缺陷。X 射线光电子能谱揭示了 SMTO 中 Mn 的混合价态的存在。磁化率和比热数据证明在TN = 6.6 _K时存在弱反铁磁有序。估计的居里-魏斯温度 θ _CW = −21 K 表明 Mn 离子之间的反铁磁相互作用。此外，磁熵和¹²⁵ Te 核自旋-晶格弛豫率都表明短程自旋相关性持续远高于 Néel 温度。我们的工作表明 Sr _0.94(2) Mn _0.86(3) Te_1.14(3) O ₆单晶实现了非中心对称的三角形反铁磁体。