Study of hyperfine interactions in V2O3 by angular correlation
Description
The hyperfine interaction in v2O3 in function of temperature by measurements of time differential perturbed angular correlation is studied. The samples presented quadrupole interaction in the probe center, Cd111 immediatelly after sintering, when reduced in H2 flux at 8000C. A pure electric quadrupole interaction at the metallic phase and a combined interaction of magnetic dipole and electric quadrupole at the insulating antiferromagnetic phase, were observed. The electric field gradient undergoes abrupt variation at the metal-insulating transition at T=1600K from 8.2x1017v/cm2 at the insulating phase to 6.3x1017v/cm2 in the metallic phase, however varies smoothly with the temperature at T=4500K when variations in resistivity also occur. At metallic phase the electric field increases with the temperature enhacement. The hyperfine magnetic field of Cd111 at antiferromagnetic phase of V2O3 has a saturation value of 15(1) KOe and performes an angle of β=68(2)0 with the main component direction of electric field gradient. (M.C.K.)
Availability note (English)
MF available from INIS under the Report Number.Abstract (Portuguese)
Estuda-se a interacao hiperfina no V2O3 em funcao da temperatura atraves de medidas de correlacao angular tempo-diferencial pertubada. As amostras apresentaram uma interacao quadripolar unica no sitio do nucleo sonda, no caso o Cd111 imediatamente apos a sinterizacao, quando foram reduzidas em fluxo de H2 a 8000C. Observaram-se uma interacao quadripolar eletrica pura na fase metalica e uma interacao combinada de dipolo magnetico e quadrupolo eletrico na fase isolante-antiferromagnetica. O gradiente de campo eletrico sofre uma variacao brusca na transicao metal-isolante em T=160 K passando de 8.2x1017 v/cm2 na fase isolante para 6,3x1017 v/cm2 na fase metalica, porem varia suavemente com a temperatura em T=450K onde tambem ocorrem variacoes na resistividade. Na fase metalica o gradiente de campo eletrico cresce com o aumento de temperatura. O campo magnetico hiperfino do Cd111 na fase antiferromagnetica do V2O3 tem um valor de saturacao de 15(1) KOe e forma um angulo β=68(2)0 com a direcao da componente principal do gradiente do campo eletrico. (autor)Files
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Additional details
Additional titles
- Original title (Portuguese)
- Estudo de interacoes hiperfinas no V
Publishing Information
- Imprint Pagination
- 88 p.
- Report number
- INIS-BR--1592
INIS
- Country of Publication
- Brazil
- Country of Input or Organization
- Brazil
- INIS RN
- 20065568
- Subject category
- S36: MATERIALS SCIENCE; S36: MATERIALS SCIENCE;
- Resource subtype / Literary indicator
- Thesis
- Descriptors DEI
- CADMIUM 111; DIFFERENTIAL PAC; HYPERFINE STRUCTURE; PHASE TRANSFORMATIONS; SINTERING; TEMPERATURE DEPENDENCE; TIME DEPENDENCE; VANADIUM OXIDES
- Descriptors DEC
- ANGULAR CORRELATION; CADMIUM ISOTOPES; CHALCOGENIDES; CORRELATIONS; EVEN-ODD NUCLEI; FABRICATION; INTERMEDIATE MASS NUCLEI; INTERNAL CONVERSION RADIOISOTO; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; MINUTES LIVING RADIOISOTOPES; NUCLEI; OXIDES; OXYGEN COMPOUNDS; PERTURBED ANGULAR CORRELATION; RADIOISOTOPES; STABLE ISOTOPES; TRANSITION ELEMENT COMPOUNDS; VANADIUM COMPOUNDS