Jahn–Teller distortions induced strong negative thermal expansion in α -Cu 2 V 2 O 7
Zhengzhou University · University of Padua · +9 more institutions
Abstract
Abstract Negative thermal expansion (NTE) refers to volume contraction upon heating, but the intrinsic complexity of its physical mechanisms presents a fundamental challenge. α -Cu 2 V 2 O 7 exhibits significant anisotropic NTE over a wider temperature range; however, its NTE mechanism has not been clearly elucidated. Herein, we systematically investigate the NTE mechanism of α -Cu 2 V 2 O 7 using neutron powder diffraction, synchrotron radiation x-ray diffraction, and temperature- and pressure-dependent Raman spectra, and density functional theory calculations across 5–800 K. The structure exhibits a second-order Jahn–Teller (SOJT) effect, which is the primary cause of off-centering within the quasi-CuO 6…
Citation impact
- FWCI
- 24.91
- Percentile
- 99%
- References
- 82
Authors
14Topics & keywords
- Negative thermal expansion
- Zigzag
- Thermal expansion
- Anisotropy
- Density functional theory
- Displacement (psychology)
- Thermal