学科分类
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1 个结果
  • 简介:AnewlayeredCu-basedoxychalcogenideBa3Fe2O5Cu2S2hasbeensynthesizedanditsmagneticandelectronicpropertieswererevealed.Ba3Fe2O5Cu2S2isbuiltupbyalternativelystacking[Cu2S2]2-layersandironperovskiteoxide[(FeO2)(BaO)(FeO2)]2-layersalongthecaxisthatareseparatedbybariumionswithFe3+fivefoldcoordinatedbyasquare-pyramidalarrangementofoxygen.Fromthebondvalencearguments,weinferredthatinlayeredCuCh-based(Ch=S,Se,Te)compoundsthe+3cationinperovskiteoxidesheetprefersasquarepyramidalsite,whilethelowervalencecationprefersthesquareplanarsites.Thestudiesonsusceptibility,transport,andopticalreflectivityindicatethatBa3Fe2O5Cu2S2isanantiferromagneticsemiconductorwithaNe′eltemperatureof121Kandanopticalbandgapof1.03eV.Themeasurementofheatcapacityfrom10Ktoroomtemperatureshowsnoanomalyat121K.TheDebyetemperatureisdeterminedtobe113K.TheoreticalcalculationsindicatethattheconductionbandminimumispredominantlycontributedbyO2pand3dstatesofFeionsthatantiferromagneticallyarrangedinFeO2layers.TheFe3dstatesarelocatedatlowerenergyandresultinanarrowbandgapincomparisonwiththatoftheisostructuralSr3Sc2O5Cu2S2.

  • 标签: 钙钛矿型氧化物 铁磁半导体 光学带隙 德拜温度 电子性质 阳离子