Spin susceptibility of boron carbides: Dissociation of singlet small bipolarons

Autor:	T. L. Aselage, Libero Zuppiroli, O. Chauvet, László Forró, David Emin
Rok vydání:	1996
Předmět:	Bipolaron chemistry.chemical_compound Materials science Condensed matter physics chemistry Spins Landé g-factor Singlet state Polaron Boron carbides Magnetic susceptibility Dissociation (chemistry)
Zdroj:	Physical Review B. 53:14450-14457
ISSN:	1095-3795 0163-1829
DOI:	10.1103/physrevb.53.14450
Popis:	Using ESR, the spin susceptibilities of a crystal and ceramics of boron carbides have been measured between 4 and 1200 K. A thermally generated contribution to the spin susceptibility, which may be discerned emerging above 100 K, becomes unmistakable above 300 K. The $g$ values of these spins differ from those of the temperature-independent background spins that dominate low-temperature ESR measurements. Thus, ESR measurements at temperatures well above those of previous works unearth thermally generated spins in boron carbides. We suggest that these thermally induced spins arise from thermal dissociation of boron carbides' singlet small bipolarons. The energy with which a small bipolaron is bound with respect to dissociating into two small polarons is estimated to be about 0.2 eV.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::02141f882d75ffecd5d22e3d3c2b71c6 https://doi.org/10.1103/physrevb.53.14450 Zobrazit plný text záznamu