Diamagnetic Susceptibility of Pyrolytic Graphite

Abstract

The diamagnetic susceptibilities of some pyrolytic graphites deposited at 2100-2300\ifmmode^\circ\else\textdegree\fi{}C have been measured at room temperature. As-deposited samples had significantly larger susceptibilities than that of well-graphitized carbons or single-crystal graphite. Heat treatment at temperatures above 2300\ifmmode^\circ\else\textdegree\fi{}C caused the total susceptibility to decrease to a minimum value, then rise and level out at a value characteristic of graphite, as a function of treatment temperature. The relationship of the susceptibility behavior to the structure of the pyrolytic graphite is discussed.