Li 二次電池正極材料斜方晶 LiMn1-xMxO2(M=Mn, Co, Ni, Zn) の MEM/Rietveld 解析及び第一原理計算による電子構造の検討

We synthesized the LiMn1-xMxO2 (M=Mn, Co, Ni) and investigated the electron density map by X-ray diffraction using the Maximum Entropy Method(MEM)/Rietveld Analysis and first principles calculation. The electron density map shows that the covalent bonding of (Mn, M)-O of o-LiMn1-xMxO2 is stronger than that of o-LiMnO2. Next, we calculated the electron density of o-LiMn1-xMxO2 (M=Mn, Co, Ni, Zn) using the first principles calculation by FLAPW method. The covalent bonding of Mn-O and M-O of each o-LiMn1-xMxO2 is stronger than that of o-LiMnO2 by substitution of Mn with M.