Materials Data on Li2FeF4 by Materials Project

Li2FeF4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a distorted see-saw-like geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.86–2.22 Å. In the second Li1+ site, Li1+ is bonded to five F1- atoms to form LiF5 square pyramids that share corners with three equivalent FeF6 octahedra, edges with two equivalent FeF6 octahedra, and an edgeedge with one LiF5 square pyramid. The corner-sharing octahedra tilt angles range from 29–66°. There are a spread of Li–F bond distances ranging from 1.92–2.11 Å. Fe2+ is bonded to six F1- atoms to form distorted FeF6 octahedra that share corners with two equivalent FeF6 octahedra, corners with three equivalent LiF5 square pyramids, an edgeedge with one FeF6 octahedra, and edges with two equivalent LiF5 square pyramids. The corner-sharing octahedral tilt angles are 51°. There are a spread of Fe–F bond distances ranging from 2.04–2.26 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted rectangular see-saw-like geometry to two Li1+ and two equivalent Fe2+ atoms. In the second F1- site, F1- is bonded in a T-shaped geometry to two Li1+ and one Fe2+ atom. In the third F1- site, F1- is bonded in a distorted see-saw-like geometry to three Li1+ and one Fe2+ atom. In the fourth F1- site, F1- is bonded to two Li1+ and two equivalent Fe2+ atoms to form distorted corner-sharing FLi2Fe2 trigonal pyramids.

Li₂FeF₄结晶于单斜晶系P2₁/c空间群，其结构为三维骨架。体系中存在两个不等价的Li⁺配位位点：在第一个Li⁺位点中，Li⁺以畸变跷跷板型配位几何与四个F⁻原子成键，Li-F键长分布范围为1.86~2.22 Å；在第二个Li⁺位点中，Li⁺与五个F⁻原子配位形成LiF₅四方锥单元，该四方锥与三个等价的FeF₆八面体共顶点、与两个等价的FeF₆八面体共边，同时与一个LiF₅四方锥共边。共顶点八面体的倾斜角范围为29°~66°，该位点的Li-F键长分布范围为1.92~2.11 Å。Fe²⁺与六个F⁻原子配位形成畸变FeF₆八面体，该八面体与两个等价的FeF₆八面体共顶点、与三个等价的LiF₅四方锥共顶点，同时与一个FeF₆八面体共边、与两个等价的LiF₅四方锥共边，其共顶点八面体的倾斜角为51°，Fe-F键长分布范围为2.04~2.26 Å。体系中存在四个不等价的F⁻配位位点：在第一个F⁻位点中，F⁻以畸变矩形跷跷板型配位几何与两个Li⁺和两个等价的Fe²⁺成键；在第二个F⁻位点中，F⁻以T型配位几何与两个Li⁺和一个Fe²⁺成键；在第三个F⁻位点中，F⁻以畸变跷跷板型配位几何与三个Li⁺和一个Fe²⁺成键；在第四个F⁻位点中，F⁻与两个Li⁺和两个等价的Fe²⁺成键，形成畸变的共顶点FLi₂Fe₂三角锥单元。

搜集汇总

背景与挑战

背景概述

该数据集提供了Li2FeF4材料的晶体结构数据，显示其结晶于单斜晶系P2_1/c空间群，具有三维结构。关键特点包括两个不等价的Li+位点分别形成扭曲几何构型，Fe2+形成扭曲八面体，以及四个不等价的F-位点通过多种键合方式连接Li和Fe原子，详细描述了原子间的键长和几何共享关系。