利用微观模型和格林函数理论,我们计算了离子掺杂的LiMPO4(LMPO)中的磁化强度和带隙能量,其中M=Fe,Ni,Co,Mn.离子掺杂,比如Nb,Ti,或Li位点的Al离子,在LiFePO4中诱导弱铁磁性。用半径较小的离子代替Li,比如Nb,Ti,或者Al,产生压缩应变,导致交换相互作用常数增加和带隙能量减少,例如,在掺杂材料中。值得注意的是,与在Li位点掺杂相比,在Fe位点掺杂Nb离子导致Eg更明显的降低,有可能增强导电性。在其他LMPO4化合物中观察到类似的Eg降低趋势。相反,取代离子半径比Fe大的离子,如Zn和Cd,导致例如增加。
Using a microscopic model and Green\'s function theory, we calculated the magnetization and band-gap energy in ion-doped LiMPO4 (LMPO), where M = Fe, Ni, Co, Mn. Ion doping, such as with Nb, Ti, or Al ions at the Li site, induces weak ferromagnetism in LiFePO4. Substituting Li with ions of a smaller radius, such as Nb, Ti, or Al, creates compressive strain, resulting in increased exchange interaction constants and a decreased band-gap energy, Eg, in the doped material. Notably, Nb ion doping at the Fe site leads to a more pronounced decrease in Eg compared to doping at the Li site, potentially enhancing conductivity. Similar trends in Eg reduction are observed across other LMPO4 compounds. Conversely, substituting ions with a larger ionic radius than Fe, such as Zn and Cd, causes an increase in Eg.