1 3 N ov 1 99 6 Electronic excitation spectra from ab - initio band structure results for La M O 3 ( M = Cr - Ni )
نویسنده
چکیده
We present calculated electron excitation spectra for the LaMO3 series (M=Cr-Ni) obtained within ab-initio band structure calculations for the real geometric and magnetic structures. The calculated results show good agreement with the experimentally obtained spectra. This suggests that the transition metal-transition metal interactions via the oxygen atom play an important role in determining the spectroscopic features and indicates a smaller value of U/t than has been believed so far. The present approach undermines the importance of multiplet interactions which otherwise play an important role within various single impurity models. PACS numbers: 71.20.-b, 71.27.+a,75.10.Lp, 75.25.+z Typeset using REVTEX
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