title: In situ study of the metal-insulator transition in VO2 by EELS and ab initio calculations.
abstract: Changes in the dielectric properties during the thermochromic transition of commercial VO(2) powders were determined in situ, by analyzing the low-loss region of the electron energy-loss spectroscopy (EELS) spectra in a transmission electron microscope at room temperature (insulator phase) and 100 degrees C (metallic phase). A comparison of experimental EELS spectra and ab initio density-functional theory calculations (WIEN2k code) within the generalized gradient approximation (GGA) is presented. A characteristic peak around 5.6 eV appears in the energy-loss function in metallic phase, which is absent in insulator phase. The origin of the characteristic peak is analyzed by means of energy-band structure calculations.
authors.affiliation: Centro de Investigación en Materiales Avanzados, S.C., Laboratorio Nacional de Nanotecnología, Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31109 Chihuahua, Chihuahua, Mexico. francisco.espinosa@cimav.edu.mx
authors.forename: F
authors.initials: F
authors.lastname: Espinosa-Magaña
authors.forename: Alberto
authors.initials: A
authors.lastname: Rosas
authors.forename: H E
authors.initials: HE
authors.lastname: Esparza-Ponce
authors.forename: M T
authors.initials: MT
authors.lastname: Ochoa-Lara
authors.forename: A
authors.initials: A
authors.lastname: Aguilar-Elguezabal