A New Insight into Cobalt Metal Powder Internal Field 59Co NMR Spectra

The authors present a new approach of internal field Co-59 NMR spectra assignment leaving apart from "usual" decomposition on "pure" hcp and fcc stackings, and a set of stacking faults (sfs) sf(1)-sf(5) with a certain lines position. The authors propose including into consideration not only cobalt structural features as well as its magnetic nature due to the strong ferromagnetism in Co metal. The last fact supposes an existence of different magnetic species such as magnetic domains, domain walls, and single-domain particles, thereby helping to spectral lines assignment according to both structural and magnetic origin. The examined sample contains fcc and hcp resonance peaks in both domains and domain walls giving the hcp to fcc ratio equal to 1.9, as well a significant amount of Co sfs, or Co in loose coordination, up to 10 %. The research exhibits a good agreement of all implemented techniques.