文档介绍：· 724 · 硅 酸 盐 学 报 2009 年
res, and a large negative thermal expansion effect in the compounds was observed. Near magnetic
transition, abrupt lattice contraction such as Mn3ZnN, Mn3CuN, Mn3SnN does not always happen. The peculiar thermal expansion
behavior of the compounds and its relationship with the different valence electrons at the X site were discussed. The results show that
the abnormal thermal expansion behavior is related to the number of valence electrons at the X site and 3 valence electrons is benefi-
cial to obtain a compound with negative thermal expansion. The negative thermal expansion coefficient value and the temperature
range of the compound could be adjusted by doping at the X site in Mn3XN. For example, the negative thermal expansion temperature
–6
range of can reach 100 K, with a thermal expansion coefficient of – × 10 /K. For Mn3GaN and ,
their lattice constants almost remain constant with the increase of temperature at around room temperature, implying the occurrence of
near zero thermal expansion.
Key word: abnormal thermal expansion; magnetic transition; anti-perovski