Determination of the mosaic angle distribution of Grafoil platelets using continuous-wave NMR spectra

Abstract

We described details of a method to estimate with good accuracy the mosaic angle distributions of microcrystallites (platelets) in exfoliated graphite like Grafoil which is commonly used as an adsorption substrate for helium thin films. The method is based on analysis of resonance field shifts in continuous-wave (CW) NMR spectra of ${}^3$He ferromagnetic monolayers making use of the large nuclear polarization of the adsorbate itself. The mosaic angle distribution of a Grafoil substrate analyzed in this way can be well fitted to a gaussian form with a $27.5\pm 2.5$ deg spread. This distribution is quite different from the previous estimation based on neutron scattering data which showed an unrealistically large isotropic powder-like component.

6 pages, 5 figures

References in corpus (2)

• Scanning tunneling microscopy and spectroscopy of the electronic local density of states of graphite surfaces near monoatomic step edges
• Spin-Echo Measurements for an Anomalous Quantum Phase of 2D Helium-3

Cited by in corpus (4)

• Observation of Self-binding in Monolayer ${}^3$He
• New Heat-Capacity Measurements of the Possible Order-Disorder Transition in the 4/7-phase of 2D Helium
• Growth of uniform helium submonolayers adsorbed on single-surface graphite observed by surface X-ray diffraction
• Spin-spin Relaxation Time Measurements of 2D ${}^3$He on Graphite