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Updated: Sep 11, 2025

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Local Structure and Optical Absorption of Mn2+ Intoxicated YPO4 Single Crystals
Maroj Bharati1, Vikram Singh1, Ram Kripal2
1Department of Physics, Nehru Gram Bharti (DU), Prayagraj, Uttar Pradesh, India.
None:
Utilizing perturbation theory and the superposition model, the zero field splitting parameters for the Mn2+ intoxicated crystals of YPO4 are obtained. Considering local distortion in the calculation, the evaluated parameters fairly match the experimental ones. Theoretical evidence corroborates the experimental inference that the Mn2+ ion substitutes at the Y3+ site in YPO4. The crystal's optical spectra are calculated by diagonalizing the total Hamiltonian in the coupling scheme for the intermediate crystal field, using the crystal field parameters determined from the superposition model and the crystal field analysis program. The calculated and experimental band positions match fairly well. Consequently, the experimental results are confirmed by the theoretical analysis.
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