Chemical bond properties and M(?)ssbauer spectroscopy in (La_(1-x)M_x)_2CuO_4(M=Ba,Sr)

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By using the average band-gap model, the chemical bond properties of (La1-xMx)2CuO4(M=Ba, Sr) were calcu-lated . The calculated covalencies for Cu-O and La-O bond in the compounds are 0.3 and 0.03 respectively. Mossbauerisomer shifts of 57Fe doped in La2CuO4 and 119Sn doped in La2CuO4 were calculated by using the chemical surroundingfactor defined by covalency and electronic polarizability. Four valence state tin and three valence iron sites were identifiedin 57Fe and 119Sn doped La2CuO4. By using the average band-gap model, the chemical bond properties of (La1-xMx) 2CuO4 (M = Ba, Sr) were calcu- lated. The calculated covalencies for Cu-O and La-O bond in the compounds were 0.3 and 0.03 respectively. Mossbauerisomer shifts of 57Fe doped in La2CuO4 and 119Sn doped in La2CuO4 were calculated by using the chemical surrounding factor defined by covalency and electronic polarizability. Four valence state tin and three valence iron sites were identified as 57Fe and 119Sn doped La2CuO4.
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