Partial molecular orbitals in face-sharing 3$d$ manganese trimer: Comparative studies on Ba$_{4}$TaMn$_{3}$O$_{12}$ and Ba$_{4}$NbMn$_{3}$O$_{12}$

Anzar Ali; Heung-Sik Kim; Poonam Yadav; Suheon Lee; Duhee Yoon; Sungkyun Choi

doi:10.1103/PhysRevResearch.6.013231

paper

Partial molecular orbitals in face-sharing 3 $d$ manganese trimer: Comparative studies on Ba $_{4}$ TaMn $_{3}$ O $_{12}$ and Ba $_{4}$ NbMn $_{3}$ O $_{12}$

arXiv:2304.14640 · doi:10.1103/PhysRevResearch.6.013231

Abstract

We present a molecular orbital candidate Ba $_{4}$ TaMn $_{3}$ O $_{12}$ with a face-sharing octahedra trimer, by comparing it with a related compound Ba $_{4}$ NbMn $_{3}$ O $_{12}$ . The synthesis of the polycrystalline powder is optimized by suppressing the secondary impurity phase via x-ray diffraction. Magnetic susceptibility measurements on the optimized samples reveal a weak magnetic hysteresis with magnetic transitions consistent with heat capacity results. The effective magnetic moments from susceptibility indicate a strongly coupled $S = 2$ antiferromagnetic trimer at around room temperature, whereas the estimated magnetic entropy from heat capacity suggests the localized $S = 3/2$ timer. These results can be explainable by a partial molecular orbital state, in which three $t_{2 g}$ electrons are localized in each Mn ion and one $e_{g}$ electron is delocalized over two-end Mn ions of the trimer based on density functional theory calculations. This unconventional 3 $d$ orbital state is comprehended as a consequence of competition between the hybrid interatomic orbitals within the Mn trimer and the local moment formation by on-site Coulomb correlations.

15 pages, 12 figures, 4 tables

Partial molecular orbitals in face-sharing 3 $d$ manganese trimer: Comparative studies on Ba $_{4}$ TaMn $_{3}$ O $_{12}$ and Ba $_{4}$ NbMn $_{3}$ O $_{12}$

Abstract

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Partial molecular orbitals in face-sharing 3d manganese trimer: Comparative studies on Ba4​TaMn3​O12​ and Ba4​NbMn3​O12​

Abstract

References in corpus (9)

Cited by in corpus (3)

Partial molecular orbitals in face-sharing 3 $d$ manganese trimer: Comparative studies on Ba $_{4}$ TaMn $_{3}$ O $_{12}$ and Ba $_{4}$ NbMn $_{3}$ O $_{12}$