Materials Data on Na2Sb4O7 by Materials Project

Na2Sb4O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.55 Å. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Sb–O bond distances ranging from 2.01–2.21 Å. In the second Sb3+ site, Sb3+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Sb–O bond distances ranging from 1.99–2.38 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Na1+ and two equivalent Sb3+ atoms to form a mixture of distorted corner and edge-sharing ONa2Sb2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Na1+ and two Sb3+ atoms to form a mixture of distorted corner and edge-sharing ONa2Sb2 tetrahedra. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three Sb3+ atoms. In the fourth O2- site, O2- is bonded to two equivalent Na1+ and two equivalent Sb3+ atoms to form a mixture of distorted corner and edge-sharing ONa2Sb2 tetrahedra.

四氧四锑化二钠（Na₂Sb₄O₇）属于单斜晶系，空间群为C2/c。其晶体结构为三维骨架结构。一价钠离子（Na⁺）以五配位几何构型与五个二价氧离子（O²⁻）成键，Na-O键的键长分布范围为2.32~2.55埃。体系中存在两个不等价的三价锑离子（Sb³⁺）格位：在第一个Sb³⁺格位中，三价锑离子以类矩形跷跷板几何构型与四个O²⁻原子成键，该格位下的Sb-O键键长分布范围为2.01~2.21埃；在第二个Sb³⁺格位中，三价锑离子以畸变类矩形跷跷板几何构型与四个O²⁻原子成键，该格位下的Sb-O键键长分布范围为1.99~2.38埃。体系中存在四个不等价的O²⁻格位：在第一个O²⁻格位中，二价氧离子与两个等价的Na⁺和两个等价的Sb³⁺成键，形成畸变角共享与边共享共存的ONa₂Sb₂四面体结构基元；在第二个O²⁻格位中，二价氧离子与两个等价的Na⁺和两个Sb³⁺成键，形成畸变角共享与边共享共存的ONa₂Sb₂四面体结构基元；在第三个O²⁻格位中，二价氧离子以三配位几何构型与三个Sb³⁺成键；在第四个O²⁻格位中，二价氧离子与两个等价的Na⁺和两个等价的Sb³⁺成键，形成畸变角共享与边共享共存的ONa₂Sb₂四面体结构基元。