@article{10902/28534,
year = {2022},
url = {https://hdl.handle.net/10902/28534},
abstract = {High-pressure optical-absorption measurements performed on polycrystalline 
Co
(
I
O
3
)
2
 samples were used to characterize the influence of pressure on the electronic 
d
–
d
 transitions associated with 
Co
2
+
 and the fundamental band gap of 
Co
(
I
O
3
)
2
. The results shed light on the electron-lattice coupling and show that 
Co
(
I
O
3
)
2
 exhibits an unusual behavior because the compression of Co–O bond distances is not coupled to pressure-induced changes induced in the unit-cell volume. Experimental results on the internal 
d
–
d
 transitions of 
Co
2
+
 have been explained based on changes in the constituent 
Co
O
6
 octahedral units using the semiempirical Tanabe-Sugano diagram. Our findings support that the high-spin ground state 
(
4
T
1
)
 is very stable in 
Co
(
I
O
3
)
2
. We have also determined the band-gap energy of 
Co
(
I
O
3
)
2
 and its pressure dependence which is highly nonlinear. According to density-functional theory band-structure calculations, this nonlinearity occurs because the bottom of the conduction band is dominated by I-5p orbitals and the top of the valence band by Co-3d and O-2p orbitals, and because the Co–O and I–O bond lengths exhibit different pressure dependences.},
organization = {This work was supported by the Generalitat Valenciana under Project No. PROMETEO 2018/123-EFIMAT and by the Spanish Research Agency (AEI) and Spanish Ministry of Science and Investigation (MCIN) under Projects No. PID2019106383GB-C41/C43 (DOI: 10.13039/501100011033) cofinanced by EU FEDER funds, No. PGC2018-101464-B-I00, and No. RED2018-102612-T. A.L. and D.E. thank the Generalitat Valenciana for the Ph.D. Fellowship No. GRISOLIAP/2019/025. R.T. acknowledges funding from the Spanish MINECO via the Juan de la Cierva Formación program (Grant No. FJC2018-036185-I). .},
publisher = {American Physical Society},
publisher = {Physical Review B, 2022, 105(11), 115204},
title = {High-pressure tuning of d-d crystal-field electronic transitions and electronic band gap in Co(I O3)2},
author = {Liang, A. and Rodríguez González, Fernando and Rodríguez Hernández, P. and Muñoz, A. and Turnbull, R. and Errandonea, D.},
}