A study of some alkali metal-furangraphite compounds and of their charge transfer characteristics

The reaction of furan on the 1st- to 6th-stage potassium-graphite compounds, as well as on some derivatives of other alkali metals, has been critically examined. The composition and the main structural features were determined and it is suggested that the formation of the ternary compound and the stage changes observed are intimately connected with a redistribution between the furan and the aromatic layers of the electron donated by the metal atom. The presence of the electron on the furan has two important consequences: an increase in the apparent volume of the molecules due to the fuzzy orbital occupied by the electron and to the repulsion between the charged species, and a long-term chemical instability of the ternary compound probably due to the presence of the electron on an antibonding orbital.