@article{10902/21957,
year = {2010},
url = {http://hdl.handle.net/10902/21957},
abstract = {Magneto-optical measurements on ruby under high-pressure conditions provided direct determination of the
trigonal crystal field acting at the t2g orbitals of Cr3+ in Al2O3  CrO6 and its dependence with pressure. The
correlation study between the measured trigonal splitting and the trigonal distortion at the Al3+-substituted site
indicates that the trigonal splitting increases with pressure whereas the trigonal distortion slightly reduces. The
result is interpreted in terms of an enhancement of the electron-lattice coupling due to trigonal distortion upon
reduction in the Al-O bond distance, i.e., the Cr-O bond distance R. The observed variations can be explained
on the basis of empirical R dependence of the trigonal crystal field as  VtrR?n with n=6. It is shown that this
exponent does not change when we consider the pressure variation of the local structure around Cr3+ obtained from ab initio calculations. By the way, we also demonstrate that a methanol-ethanol mixture is a good
pressure transmitting medium at cryogenic temperatures},
organization = {Financial support from the Spanish Ministerio de Ciencia e Innovación  Project No. MAT2008-06873-C02-01,
MALTA INGENIO-CONSOLIDER 2010 Grant No. CDS2007-0045, and EuroMagnet II FP7 program are acknowledged.},
publisher = {American Physical Society},
publisher = {Physical review. B, 2010, 81, 075120},
title = {Trigonal field acting at the Cr3+ 2 E states in ruby from magneto-optical measurements under high pressure},
author = {Millot, Marius and Broto, Jean-Marc and González Gómez, Jesús Antonio and Rodríguez González, Fernando},
}