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/

Journal Article · Tue Dec 01 04:00:00 EST 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.36.8213· OSTI ID:5679848

Zhang, Y D; Budnick, J I; Wojcik, M; Potenziani, II, E; Pedziwiatr, A T; Wallace, W E

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

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
&amp; 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