NMR study of Fe hyperfine field assignments in Nd/sub 15/Fe/sub 77/B/sub 8/ and Co site preference in Nd/sub 15/Fe/sub 77-//sub x/Co/sub x/B/sub 8/
The /sup 10/B, /sup 11/B, and /sup 57/Fe hyperfine field distributions for /sup 10/B-enriched Nd/sub 15/Fe/sub 77/B/sub 8/ and Nd/sub 15/Fe/sub 77-//sub x/Co/sub x/B/sub 8/ (x<12) were measured by spin-echo NMR at 1.3 and 4.2 K for frequencies from 10 to 70 MHz. Using 98% /sup 10/B enrichment makes the /sup 57/Fe resonances more pronounced, which enabled us to precisely determine the hyperfine field values. As suggested by the spin-echo amplitudes and the frequency shifts caused by Co substitution, the assignment of the measured hyperfine fields of Nd/sub 15/Fe/sub 77/B/sub 8/ to the six Fe sites is tentatively the following: 378(j/sub 2/), 352(k/sub 2/), 334(j/sub 1/), 325(k/sub 1/), 320(c), and 302(e) kOe. The substitution of Co for Fe decreases the hyperfine fields at the Fe nuclei at the j/sub 2/, k/sub 2/, j/sub 1/, k/sub 1/, and c sites, while no obvious change in the hyperfine field at the e-site Fe nuclei nor at the B nuclei has been found. The spin-echo amplitude corresponding to the Fe(k/sub 2/) site line decreases drastically with Co content. These results demonstrate that Co atoms have a strong preference to substitute for the Fe(k/sub 2/) atoms.
- Research Organization:
- Department of Physics and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06268
- OSTI ID:
- 5679848
- Journal Information:
- Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 36:16; ISSN PRBMD
- Country of Publication:
- United States
- Language:
- English
Similar Records
sup 57 Fe Moessbauer studies of Nd sub 2 Fe sub 14 B and Nd sub 2 Fe sub 12. 5 Si sub 1. 5 B ( T =77--300 K)
Magnetic field dependence of /sup 11/B and /sup 57/Fe NMR in a Nd/sub 2/Fe/sub 14/B compound (abstract)
Related Subjects
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
BORIDES
BORON 10
BORON 11
BORON COMPOUNDS
BORON ISOTOPES
COBALT BORIDES
COBALT COMPOUNDS
COHERENT SCATTERING
CURRENTS
DIFFRACTION
ELECTRIC ARCS
ELECTRIC CURRENTS
ELECTRIC DISCHARGES
ELECTRONIC STRUCTURE
EVEN-ODD NUCLEI
FREQUENCY RANGE
HYPERFINE STRUCTURE
INTERMEDIATE MASS NUCLEI
IRON 57
IRON BORIDES
IRON COMPOUNDS
IRON ISOTOPES
ISOTOPES
LATTICE PARAMETERS
LIGHT NUCLEI
MAGNETIC FIELDS
MELTING
MHZ RANGE
MHZ RANGE 01-100
NEODYMIUM BORIDES
NEODYMIUM COMPOUNDS
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
PHASE TRANSFORMATIONS
RARE EARTH COMPOUNDS
SCATTERING
SPIN ECHO
STABLE ISOTOPES
TRANSITION ELEMENT COMPOUNDS
ULTRALOW TEMPERATURE
X-RAY DIFFRACTION