TY  - JOUR
AU  - Nevgi, Rukma
AU  - Dey, Subha
AU  - Bhattacharya, Nandana
AU  - Ershadrad, Soheil
AU  - Dan, Tinku
AU  - Chakravarty, Sujay
AU  - Kaushik, S. D.
AU  - Klewe, Christoph
AU  - Sterbinsky, George E.
AU  - Sanyal, Biplab
AU  - Middey, Srimanta
TI  - Local structural distortions drive magnetic molecular field in compositionally complex spinel oxide
JO  - Nature Communications
VL  - 16
IS  - 1
SN  - 2041-1723
CY  - [London]
PB  - Springer Nature
M1  - PUBDB-2025-03918
SP  - 7038
PY  - 2025
AB  - Understanding how local distortions determine the functional properties of high entropy materials, containing five or more elements at the same crystallographic site, is an open challenge. We address this for a compositionally complex spinel oxide (Mn<sub>0.2</sub>Co<sub>0.2</sub>Ni<sub>0.2</sub>Cu<sub>0.2</sub>Zn<sub>0.2</sub>)Cr<sub>2</sub>O<sub>4</sub> (A<sub>5</sub>Cr<sub>2</sub>O<sub>4</sub>). By comparatively examining extended X-ray absorption fine structure on A<sub>5</sub>Cr<sub>2</sub>O<sub>4</sub> and its parent counterparts, ACr<sub>2</sub>O<sub>4</sub>, along with density functional theory calculations for multiple configurations, we find that the element-specific distortions go beyond the first neighbor. Specifically, the strong Jahn-Teller distortion present in CuCr<sub>2</sub>O<sub>4</sub> is found to be completely suppressed in A<sub>5</sub>Cr<sub>2</sub>O<sub>4</sub> even locally. Instead, there is a broad distribution of Cu-O and Cu-Cr bond distances, while other A-O distances acquire certain specific values. This study demonstrates the additional flexibility of a cationic sublattice in maintaining a uniform long-range structure, in contrast to previous reports showing only the accommodative anionic sublattice. The mean-field magnetic interactions of A<sub>5</sub>Cr<sub>2</sub>O<sub>4</sub> exhibit a striking resemblance to those of NiCr<sub>2</sub>O<sub>4</sub>, despite the presence of multiple magnetic ions and variable bond lengths. This originates from the comparability of bond lengths around Cr in both materials. Our study paves the way for a deeper understanding of the impact of local structural distortions on the physical properties of compositionally complex quantum materials.  
LB  - PUB:(DE-HGF)16
C6  - pmid:40745166
DO  - DOI:10.1038/s41467-025-62268-x
UR  - https://bib-pubdb1.desy.de/record/637928
ER  -