New empirical relation for chemical shift and effective charge in the X-ray absorption edge shifts
Bunty Rani Roy1, Nageswara Rao A S1, Ramana Rao G1
1Department of Physics, Kakatiya University, Warangal, 506009, Telangana State, India.
Abstract:
A new relation, ΔE = aebq, between the chemical shift ΔE and effective charge 'q' is proposed. It has been shown that the relation generates polynomial relations, between ΔE and 'q' used by earlier investigators and addresses their short-comings effectively. Further, four possible sign combinations of 'q' and ΔE are accounted for using the proposed equation. Units of arbitrary constants 'a' and 'b' are derived. The tendency of 'q' to attain saturation value is also explained. The success of the new relation has been tested using its linearized form ln ∣ ΔE ∣ = ln ∣ a ∣ + bq for a large number of compounds, by taking their experimental X-ray absorption edge shifts along with corresponding values of 'q' from the available literature. In the process, the claim of earlier workers regarding linear relationship between ΔE and 'q' and ΔE and 'qX', where 'X' is the electronegativity, has been found incorrect in the case of 6p6 isoelectronic series of compounds.
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