Research Information System
BRAZILIAN JOURNAL OF PHYSICS, vol.56, no.2, 2025 (SCI-Expanded, Scopus)
Experimental studies have shown that NdFe4P12 is a metal with a ferromagnetic ordering. The main objective of this study is to investigate its vibrational behavior and its effect on the lattice thermal conductivity and a detailed study on the magnetic and electronic properties as well as to determine its lattice thermal conductivity and thermoelectric figure of merit. Phonon dispersion curve has shown, for the first time, the absence of soft modes, confirming that NdFe4P12 is dynamically stable. The rattling role of Nd-atoms in the acoustic branches enhances phonon scattering and reduces the lattice thermal conductivity, however, the absence of overlap between the acoustic and optical branches limits this enhancement. This is supported by the calculated lattice thermal conductivity, which is about 6.94 W.m(- 1).K- 1 at 300 K. Such a value is moderate for a metal but relatively high for thermoelectric applications. Nevertheless, this moderate LTC remains encouraging for future optimization strategies. The found results also showed that NdFe4P12 is mechanically stable with a low elastic anisotropy. Unlike GGA and GGA + U, which showed that NdFe4P12 is ferrimagnetic, GGA + U + SOC has confirmed the ferromagnetic behavior. Using the exchange coupling parameters J(ij), the Curie temperature estimated by Mean-Field Approximation (MFA) is 8.04 K.