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arXiv · 1512.06328

Phonon Spectrum in Hydroxyapatite: Calculations and EPR Study at Low Temperatures

Timur Biktagirov·Marat Gafurov·Kamila Iskhakova·Georgy Mamin·Sergei Orlinskii
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Abstract

Density functional theory based calculations within the framework of the plane-wave pseudopotential approach are carried out to define the phonon spectrum of hydroxyapatite Ca10(PO4)6(OH)2 (HAp). It allows to describe the temperature dependence of the electronic spin-lattice relaxation time T1e of the radiation-induced stable radical NO32- in HAp, which was measured in X-band (9 GHz, magnetic field strength of 0.34 T) in the temperature range T = (10-300) K. It is shown that the temperature behavior of T1e at T > 20 K can be fitted via two phonon Raman type processes with the Debye temperature of 280 K evaluated from the phonon spectrum.

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Timur Biktagirov, Marat Gafurov, Kamila Iskhakova, Georgy Mamin, Sergei Orlinskii. 2015-12-20. Phonon Spectrum in Hydroxyapatite: Calculations and EPR Study at Low Temperatures. https://doi.org/10.1007/s10909-015-1419-2

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