Single crystals of Nb₂Pd_xSe₅ have been grown covering a broad range of palladium stoichiometries from x = 0.68–0.95 (Pd2 occupancies of 0.36 and 0.90, respectively). Miscibility gaps in the Pd stoichiometry range are related to superstructures resulting from staged filling and ordering of the partially filled Pd atom site (Pd2, Wyckoff site 2a). For Pd2 near 1/2 occupancy, a superstructure based on an incommensurate occupation wave with modulation along the monoclinic b axis is identified. A superconducting dome is found for Pd2 occupancies above 0.58 with a maximum T_c for Pd2 occupancy of ∼2/3. DFT calculations for the fully and 1/2-occupied Pd2 site show that Nb₂Pd_xSe₅ can be considered an intercalation compound for Pd2 occupancy above the minimum required for structural stability.

中文翻译：

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Nb ₂ Pd _x Se _5中与Pd嵌入相关的超结构和超导电性

Nb ₂ Pd _x Se _5的单晶已经生长，覆盖了从x = 0.68-0.95（Pd2的占有率分别为0.36和0.90）的宽范围的钯化学计量。Pd化学计量范围内的可混溶间隙与部分填充的Pd原子位点（Pd2，Wyckoff位点2a）的分阶段填充和有序化所导致的超结构有关。对于接近1/2占用的Pd2，确定了基于沿单斜b轴调制的不等占有波的上层建筑。发现Pd2占有率超过0.58的超导圆顶，Pd2占有率的最大T _c为约2/3。完全和1/2占用的Pd2站点的DFT计算表明，Nb₂ Pd _x Se ₅可以认为是Pd2占有率高于结构稳定性所需最小值的插层化合物。