Syntheses and Characteristics of $Ln_xCa_{2-x}MnO_4$ {Ln=Gd, Nd, Pr, Sm}

$Ln_xCa_{2-x}MnO_4$ 상의 합성과 특성에 관한 연구 {Ln=Gd, Nd, Pr, Sm}

  • Seo, Sang-Il (Dept. of Materials and Metallurgical Engineerng, Yeungnam Univ.) ;
  • Lee, Jai-Yeoul (Dept. of Materials and Metallurgical Engineerng, Yeungnam Univ.)
  • 서상일 (영남대학교 재료금속공학부) ;
  • 이재열 (영남대학교 재료금속공학부)
  • Published : 2000.05.13

Abstract

Since the reports of CMR(colossal magnetoresistance) effects in some single crystal R-P phase $La_{1+x}Sr_{2-x}Mn_2O_7$, considerable researches have been carried out to find optimum composition and to understand the role of dimensionality in the CMR mechanism of this system. In this study, layered perovskite $Ln_xCa_{1-x}MnO_{4}$ (x=0.5, Ln=Pr, Nd, Sm, Gd) phases were synthesized by solid state reaction and their structures were refined by Rietveld method. Electrical and magnetic properties were measured between room temperature and liquid helium temperature and compared with those of two dimensional $La_{1.4}Sr_{1.6}Mn_2O_7$ phase.

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