Influence of the core‐hole effect on optical properties of magnesium oxide (MgO) near the Mg L‐edge region. (30th March 2018)

• Record Type: Journal Article
• Authors: Sinha, Mangalika; Modi, Mohammed H.; Ghosh, Haranath; Yadav, P. K.; Gupta, R. K.
• Is Part Of: Journal of synchrotron radiation. Volume 25:Part 3(2018)
• Page Start: 771
• Page End: 776
• Publication Date: 2018-03-30
• Subjects: synchrotron radiation -- soft X‐ray -- magnesium compound -- core‐hole effect -- optical property; Synchrotron radiation -- Periodicals; Free electron lasers -- Periodicals; 539.73505
• DOI: 10.1107/S1600577518002771
• Languages: English
• ISSNs: 0909-0495

Abstract

Abstract : Optical constants of MgO thin film in the energy range 40–300 eV are reported and the influence of the core‐hole effect on the optical constants near the Mg L ‐edge region are discussed. Abstract : The influence of the core‐hole effect on optical properties of magnesium oxide (MgO) is established through experimental determination of optical constants and first‐principles density functional theory studies. Optical constants (δ and β) of MgO thin film are measured in the spectral region 40–300 eV using reflectance spectroscopy techniques at the Indus‐1 synchrotron radiation source. The obtained optical constants show strong core exciton features near the Mg L ‐edge region, causing significant mismatch with Henke's tabulated values. On comparing the experimentally obtained optical constants with Henke's tabulated values, an edge shift of ∼3.0 eV is also observed. Distinct evidence of effects of core exciton on optical constants (δ and β) in the near Mg L ‐edge absorption spectra are confirmed through first‐principles simulations.