Abstract The crystal structure, electron energy-loss spectroscopy (EELS), heat capacity, and anisotropic magnetic and resistivity measurements are reported for Sn flux grown single crystals of orthorhombic Pr2Co3Ge5(U2Co3Si5-type,Ibam). Our findings show thato-Pr2Co3Ge5hosts nearly trivalent Pr ions, as evidenced by EELS and fits to temperature dependent magnetic susceptibility measurements. Complex magnetic ordering with a partially spin-polarized state emerges nearTsp= 32 K, with a spin reconfiguration transition nearTM= 15 K. Heat capacity measurements show that the phase transitions appear as broad peaks in the vicinity ofTspandTM. The magnetic entropy further reveals that crystal electric field splitting lifts the Hund’s rule degeneracy at low temperatures. Taken together, these measurements show that Pr2Co3Ge5is an environment for complexfstate magnetism with potential strongly correlated electron states. 
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                            Mn substitution in the topological metal Zr 2 Te 2 P
                        
                    
    
            Abstract Results are reported for Mn intercalated Zr 2 Te 2 P, where x-ray diffraction , energy dispersive spectroscopy, and transmission electron microscopy measurements reveal that the van der Waals bonded Te–Te layers are partially filled by Zr and Mn ions. This leads to the chemical formulas Zr 0.07 Zr 2 Te 2 P and Mn 0.06 Zr 0.03 Zr 2 Te 2 P for the parent and substituted compounds, respectively. The impact of the Mn ions is seen in the anisotropic magnetic susceptibility, where Curie–Weiss fits to the data indicate that the Mn ions are in the divalent state. Heat capacity and electrical transport measurements reveal metallic behavior, but the electronic coefficient of the heat capacity ( γ Mn ≈ 36.6 mJ (mol·K 2 ) −1 ) is enhanced by comparison to that of the parent compound. Magnetic ordering is seen at T M ≈ 4  K, where heat capacity measurements additionally show that the phase transition is broad, likely due to the disordered Mn distribution. This transition also strongly reduces the electronic scattering seen in the normalized electrical resistance. These results show that Mn substitution simultaneously introduces magnetic interactions and tunes the electronic state, which improves prospects for inducing novel behavior in Zr 2 Te 2 P and the broader family of ternary tetradymites. 
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                            - Award ID(s):
- 1904361
- PAR ID:
- 10376760
- Date Published:
- Journal Name:
- Journal of Physics: Condensed Matter
- Volume:
- 34
- Issue:
- 48
- ISSN:
- 0953-8984
- Page Range / eLocation ID:
- 485501
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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