STUDY OF VIBRATION MODES AT HIGH PRESSURES IN LAYERED PEROVSKITE-LIKE Nd2Ti2O7
A.G. Asadov1,2, A.İ. Mammadov1, D.P. Kozlenko2, S.E. Kiçanov2, R.Z. Mehdiyeva1, E.V. Lukin2, O.N. Lis2, R.E. Huseynov1, E.R. Huseynova1, Kh.I. Akhmedov1
2024   C   az   p.53-57

ABSTRACT

The vibrational properties of a layered Nd2Ti2O7 have been studied by means Raman spectroscopy at pressures up to 30 GPa. The gradual structural phase transition from the initial monoclinic P21 ( C22) phase to the monoclinic P2 (C12) phase was observed at P ~ 19 GPa. The role of pressure application as a trigger for a significant rotation of the TiO6 octahedra, alterations in interatomic distances, and the displacement of Nd atoms were discussed.

Keywords: phase transitions, small angle scattering, crystal structure of the compound Nd2Ti2O7, Raman scattering.
DOI:10.70784/azip.3.2024C53

Received: 2024
Internet publishing: 2024

AUTHORS & AFFILIATIONS

1. Institute of Physics Ministry of Science and Education Republic of Azerbaijan, 131 H.Javid ave. Baku, AZ-1073
2. Frank Laboratory of Neutron Physics, JINR, 141980 Dubna, Russia
E-mail: asifasadov@jinr.ru

Graphics and Images

        

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