Materials Data on KFeO2 by Materials Project

KFeO2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.61–3.13 Å. Fe3+ is bonded to four O2- atoms to form a mixture of edge and corner-sharing FeO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.91–1.95 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent K1+ and two equivalent Fe3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent K1+ and two equivalent Fe3+ atoms.

KFeO₂晶体属于单斜晶系C2/m空间群，其结构为三维框架结构。K⁺（K1+）以六配位构型与六个O²⁻（O2-）离子成键，K-O键的键长分布范围为2.61~3.13 Å。Fe³⁺（Fe3+）与四个O²⁻离子成键，形成兼具共棱与共顶点连接特征的FeO₄四面体；Fe-O键的键长分布范围为1.91~1.95 Å。该晶体存在两个不等价的O²⁻离子位点：在第一类O²⁻位点中，O²⁻以矩形跷跷板型构型分别与两个等价的K⁺和两个等价的Fe³⁺成键；在第二类O²⁻位点中，O²⁻以二配位构型分别与四个等价的K⁺和两个等价的Fe³⁺成键。